Bug Summary

File:build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/clang/lib/Sema/SemaInit.cpp
Warning:line 9163, column 25
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name SemaInit.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm -resource-dir /usr/lib/llvm-16/lib/clang/16.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/clang/lib/Sema -I /build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/clang/include -I tools/clang/include -I include -I /build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/llvm/include -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-16/lib/clang/16.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm=build-llvm -fmacro-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/= -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm=build-llvm -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/= -O3 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-misleading-indentation -std=c++17 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm -fdebug-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/build-llvm=build-llvm -fdebug-prefix-map=/build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2022-09-04-125545-48738-1 -x c++ /build/llvm-toolchain-snapshot-16~++20220904122748+c444af1c20b3/clang/lib/Sema/SemaInit.cpp
1//===--- SemaInit.cpp - Semantic Analysis for Initializers ----------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements semantic analysis for initializers.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/AST/ASTContext.h"
14#include "clang/AST/DeclObjC.h"
15#include "clang/AST/ExprCXX.h"
16#include "clang/AST/ExprObjC.h"
17#include "clang/AST/ExprOpenMP.h"
18#include "clang/AST/TypeLoc.h"
19#include "clang/Basic/CharInfo.h"
20#include "clang/Basic/SourceManager.h"
21#include "clang/Basic/TargetInfo.h"
22#include "clang/Sema/Designator.h"
23#include "clang/Sema/Initialization.h"
24#include "clang/Sema/Lookup.h"
25#include "clang/Sema/SemaInternal.h"
26#include "llvm/ADT/APInt.h"
27#include "llvm/ADT/PointerIntPair.h"
28#include "llvm/ADT/SmallString.h"
29#include "llvm/Support/ErrorHandling.h"
30#include "llvm/Support/raw_ostream.h"
31
32using namespace clang;
33
34//===----------------------------------------------------------------------===//
35// Sema Initialization Checking
36//===----------------------------------------------------------------------===//
37
38/// Check whether T is compatible with a wide character type (wchar_t,
39/// char16_t or char32_t).
40static bool IsWideCharCompatible(QualType T, ASTContext &Context) {
41 if (Context.typesAreCompatible(Context.getWideCharType(), T))
42 return true;
43 if (Context.getLangOpts().CPlusPlus || Context.getLangOpts().C11) {
44 return Context.typesAreCompatible(Context.Char16Ty, T) ||
45 Context.typesAreCompatible(Context.Char32Ty, T);
46 }
47 return false;
48}
49
50enum StringInitFailureKind {
51 SIF_None,
52 SIF_NarrowStringIntoWideChar,
53 SIF_WideStringIntoChar,
54 SIF_IncompatWideStringIntoWideChar,
55 SIF_UTF8StringIntoPlainChar,
56 SIF_PlainStringIntoUTF8Char,
57 SIF_Other
58};
59
60/// Check whether the array of type AT can be initialized by the Init
61/// expression by means of string initialization. Returns SIF_None if so,
62/// otherwise returns a StringInitFailureKind that describes why the
63/// initialization would not work.
64static StringInitFailureKind IsStringInit(Expr *Init, const ArrayType *AT,
65 ASTContext &Context) {
66 if (!isa<ConstantArrayType>(AT) && !isa<IncompleteArrayType>(AT))
67 return SIF_Other;
68
69 // See if this is a string literal or @encode.
70 Init = Init->IgnoreParens();
71
72 // Handle @encode, which is a narrow string.
73 if (isa<ObjCEncodeExpr>(Init) && AT->getElementType()->isCharType())
74 return SIF_None;
75
76 // Otherwise we can only handle string literals.
77 StringLiteral *SL = dyn_cast<StringLiteral>(Init);
78 if (!SL)
79 return SIF_Other;
80
81 const QualType ElemTy =
82 Context.getCanonicalType(AT->getElementType()).getUnqualifiedType();
83
84 switch (SL->getKind()) {
85 case StringLiteral::UTF8:
86 // char8_t array can be initialized with a UTF-8 string.
87 if (ElemTy->isChar8Type())
88 return SIF_None;
89 [[fallthrough]];
90 case StringLiteral::Ordinary:
91 // char array can be initialized with a narrow string.
92 // Only allow char x[] = "foo"; not char x[] = L"foo";
93 if (ElemTy->isCharType())
94 return (SL->getKind() == StringLiteral::UTF8 &&
95 Context.getLangOpts().Char8)
96 ? SIF_UTF8StringIntoPlainChar
97 : SIF_None;
98 if (ElemTy->isChar8Type())
99 return SIF_PlainStringIntoUTF8Char;
100 if (IsWideCharCompatible(ElemTy, Context))
101 return SIF_NarrowStringIntoWideChar;
102 return SIF_Other;
103 // C99 6.7.8p15 (with correction from DR343), or C11 6.7.9p15:
104 // "An array with element type compatible with a qualified or unqualified
105 // version of wchar_t, char16_t, or char32_t may be initialized by a wide
106 // string literal with the corresponding encoding prefix (L, u, or U,
107 // respectively), optionally enclosed in braces.
108 case StringLiteral::UTF16:
109 if (Context.typesAreCompatible(Context.Char16Ty, ElemTy))
110 return SIF_None;
111 if (ElemTy->isCharType() || ElemTy->isChar8Type())
112 return SIF_WideStringIntoChar;
113 if (IsWideCharCompatible(ElemTy, Context))
114 return SIF_IncompatWideStringIntoWideChar;
115 return SIF_Other;
116 case StringLiteral::UTF32:
117 if (Context.typesAreCompatible(Context.Char32Ty, ElemTy))
118 return SIF_None;
119 if (ElemTy->isCharType() || ElemTy->isChar8Type())
120 return SIF_WideStringIntoChar;
121 if (IsWideCharCompatible(ElemTy, Context))
122 return SIF_IncompatWideStringIntoWideChar;
123 return SIF_Other;
124 case StringLiteral::Wide:
125 if (Context.typesAreCompatible(Context.getWideCharType(), ElemTy))
126 return SIF_None;
127 if (ElemTy->isCharType() || ElemTy->isChar8Type())
128 return SIF_WideStringIntoChar;
129 if (IsWideCharCompatible(ElemTy, Context))
130 return SIF_IncompatWideStringIntoWideChar;
131 return SIF_Other;
132 }
133
134 llvm_unreachable("missed a StringLiteral kind?")::llvm::llvm_unreachable_internal("missed a StringLiteral kind?"
, "clang/lib/Sema/SemaInit.cpp", 134)
;
135}
136
137static StringInitFailureKind IsStringInit(Expr *init, QualType declType,
138 ASTContext &Context) {
139 const ArrayType *arrayType = Context.getAsArrayType(declType);
140 if (!arrayType)
141 return SIF_Other;
142 return IsStringInit(init, arrayType, Context);
143}
144
145bool Sema::IsStringInit(Expr *Init, const ArrayType *AT) {
146 return ::IsStringInit(Init, AT, Context) == SIF_None;
147}
148
149/// Update the type of a string literal, including any surrounding parentheses,
150/// to match the type of the object which it is initializing.
151static void updateStringLiteralType(Expr *E, QualType Ty) {
152 while (true) {
153 E->setType(Ty);
154 E->setValueKind(VK_PRValue);
155 if (isa<StringLiteral>(E) || isa<ObjCEncodeExpr>(E)) {
156 break;
157 } else if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
158 E = PE->getSubExpr();
159 } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
160 assert(UO->getOpcode() == UO_Extension)(static_cast <bool> (UO->getOpcode() == UO_Extension
) ? void (0) : __assert_fail ("UO->getOpcode() == UO_Extension"
, "clang/lib/Sema/SemaInit.cpp", 160, __extension__ __PRETTY_FUNCTION__
))
;
161 E = UO->getSubExpr();
162 } else if (GenericSelectionExpr *GSE = dyn_cast<GenericSelectionExpr>(E)) {
163 E = GSE->getResultExpr();
164 } else if (ChooseExpr *CE = dyn_cast<ChooseExpr>(E)) {
165 E = CE->getChosenSubExpr();
166 } else {
167 llvm_unreachable("unexpected expr in string literal init")::llvm::llvm_unreachable_internal("unexpected expr in string literal init"
, "clang/lib/Sema/SemaInit.cpp", 167)
;
168 }
169 }
170}
171
172/// Fix a compound literal initializing an array so it's correctly marked
173/// as an rvalue.
174static void updateGNUCompoundLiteralRValue(Expr *E) {
175 while (true) {
176 E->setValueKind(VK_PRValue);
177 if (isa<CompoundLiteralExpr>(E)) {
178 break;
179 } else if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
180 E = PE->getSubExpr();
181 } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
182 assert(UO->getOpcode() == UO_Extension)(static_cast <bool> (UO->getOpcode() == UO_Extension
) ? void (0) : __assert_fail ("UO->getOpcode() == UO_Extension"
, "clang/lib/Sema/SemaInit.cpp", 182, __extension__ __PRETTY_FUNCTION__
))
;
183 E = UO->getSubExpr();
184 } else if (GenericSelectionExpr *GSE = dyn_cast<GenericSelectionExpr>(E)) {
185 E = GSE->getResultExpr();
186 } else if (ChooseExpr *CE = dyn_cast<ChooseExpr>(E)) {
187 E = CE->getChosenSubExpr();
188 } else {
189 llvm_unreachable("unexpected expr in array compound literal init")::llvm::llvm_unreachable_internal("unexpected expr in array compound literal init"
, "clang/lib/Sema/SemaInit.cpp", 189)
;
190 }
191 }
192}
193
194static void CheckStringInit(Expr *Str, QualType &DeclT, const ArrayType *AT,
195 Sema &S) {
196 // Get the length of the string as parsed.
197 auto *ConstantArrayTy =
198 cast<ConstantArrayType>(Str->getType()->getAsArrayTypeUnsafe());
199 uint64_t StrLength = ConstantArrayTy->getSize().getZExtValue();
200
201 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
202 // C99 6.7.8p14. We have an array of character type with unknown size
203 // being initialized to a string literal.
204 llvm::APInt ConstVal(32, StrLength);
205 // Return a new array type (C99 6.7.8p22).
206 DeclT = S.Context.getConstantArrayType(IAT->getElementType(),
207 ConstVal, nullptr,
208 ArrayType::Normal, 0);
209 updateStringLiteralType(Str, DeclT);
210 return;
211 }
212
213 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT);
214
215 // We have an array of character type with known size. However,
216 // the size may be smaller or larger than the string we are initializing.
217 // FIXME: Avoid truncation for 64-bit length strings.
218 if (S.getLangOpts().CPlusPlus) {
219 if (StringLiteral *SL = dyn_cast<StringLiteral>(Str->IgnoreParens())) {
220 // For Pascal strings it's OK to strip off the terminating null character,
221 // so the example below is valid:
222 //
223 // unsigned char a[2] = "\pa";
224 if (SL->isPascal())
225 StrLength--;
226 }
227
228 // [dcl.init.string]p2
229 if (StrLength > CAT->getSize().getZExtValue())
230 S.Diag(Str->getBeginLoc(),
231 diag::err_initializer_string_for_char_array_too_long)
232 << Str->getSourceRange();
233 } else {
234 // C99 6.7.8p14.
235 if (StrLength-1 > CAT->getSize().getZExtValue())
236 S.Diag(Str->getBeginLoc(),
237 diag::ext_initializer_string_for_char_array_too_long)
238 << Str->getSourceRange();
239 }
240
241 // Set the type to the actual size that we are initializing. If we have
242 // something like:
243 // char x[1] = "foo";
244 // then this will set the string literal's type to char[1].
245 updateStringLiteralType(Str, DeclT);
246}
247
248//===----------------------------------------------------------------------===//
249// Semantic checking for initializer lists.
250//===----------------------------------------------------------------------===//
251
252namespace {
253
254/// Semantic checking for initializer lists.
255///
256/// The InitListChecker class contains a set of routines that each
257/// handle the initialization of a certain kind of entity, e.g.,
258/// arrays, vectors, struct/union types, scalars, etc. The
259/// InitListChecker itself performs a recursive walk of the subobject
260/// structure of the type to be initialized, while stepping through
261/// the initializer list one element at a time. The IList and Index
262/// parameters to each of the Check* routines contain the active
263/// (syntactic) initializer list and the index into that initializer
264/// list that represents the current initializer. Each routine is
265/// responsible for moving that Index forward as it consumes elements.
266///
267/// Each Check* routine also has a StructuredList/StructuredIndex
268/// arguments, which contains the current "structured" (semantic)
269/// initializer list and the index into that initializer list where we
270/// are copying initializers as we map them over to the semantic
271/// list. Once we have completed our recursive walk of the subobject
272/// structure, we will have constructed a full semantic initializer
273/// list.
274///
275/// C99 designators cause changes in the initializer list traversal,
276/// because they make the initialization "jump" into a specific
277/// subobject and then continue the initialization from that
278/// point. CheckDesignatedInitializer() recursively steps into the
279/// designated subobject and manages backing out the recursion to
280/// initialize the subobjects after the one designated.
281///
282/// If an initializer list contains any designators, we build a placeholder
283/// structured list even in 'verify only' mode, so that we can track which
284/// elements need 'empty' initializtion.
285class InitListChecker {
286 Sema &SemaRef;
287 bool hadError = false;
288 bool VerifyOnly; // No diagnostics.
289 bool TreatUnavailableAsInvalid; // Used only in VerifyOnly mode.
290 bool InOverloadResolution;
291 InitListExpr *FullyStructuredList = nullptr;
292 NoInitExpr *DummyExpr = nullptr;
293
294 NoInitExpr *getDummyInit() {
295 if (!DummyExpr)
296 DummyExpr = new (SemaRef.Context) NoInitExpr(SemaRef.Context.VoidTy);
297 return DummyExpr;
298 }
299
300 void CheckImplicitInitList(const InitializedEntity &Entity,
301 InitListExpr *ParentIList, QualType T,
302 unsigned &Index, InitListExpr *StructuredList,
303 unsigned &StructuredIndex);
304 void CheckExplicitInitList(const InitializedEntity &Entity,
305 InitListExpr *IList, QualType &T,
306 InitListExpr *StructuredList,
307 bool TopLevelObject = false);
308 void CheckListElementTypes(const InitializedEntity &Entity,
309 InitListExpr *IList, QualType &DeclType,
310 bool SubobjectIsDesignatorContext,
311 unsigned &Index,
312 InitListExpr *StructuredList,
313 unsigned &StructuredIndex,
314 bool TopLevelObject = false);
315 void CheckSubElementType(const InitializedEntity &Entity,
316 InitListExpr *IList, QualType ElemType,
317 unsigned &Index,
318 InitListExpr *StructuredList,
319 unsigned &StructuredIndex,
320 bool DirectlyDesignated = false);
321 void CheckComplexType(const InitializedEntity &Entity,
322 InitListExpr *IList, QualType DeclType,
323 unsigned &Index,
324 InitListExpr *StructuredList,
325 unsigned &StructuredIndex);
326 void CheckScalarType(const InitializedEntity &Entity,
327 InitListExpr *IList, QualType DeclType,
328 unsigned &Index,
329 InitListExpr *StructuredList,
330 unsigned &StructuredIndex);
331 void CheckReferenceType(const InitializedEntity &Entity,
332 InitListExpr *IList, QualType DeclType,
333 unsigned &Index,
334 InitListExpr *StructuredList,
335 unsigned &StructuredIndex);
336 void CheckVectorType(const InitializedEntity &Entity,
337 InitListExpr *IList, QualType DeclType, unsigned &Index,
338 InitListExpr *StructuredList,
339 unsigned &StructuredIndex);
340 void CheckStructUnionTypes(const InitializedEntity &Entity,
341 InitListExpr *IList, QualType DeclType,
342 CXXRecordDecl::base_class_range Bases,
343 RecordDecl::field_iterator Field,
344 bool SubobjectIsDesignatorContext, unsigned &Index,
345 InitListExpr *StructuredList,
346 unsigned &StructuredIndex,
347 bool TopLevelObject = false);
348 void CheckArrayType(const InitializedEntity &Entity,
349 InitListExpr *IList, QualType &DeclType,
350 llvm::APSInt elementIndex,
351 bool SubobjectIsDesignatorContext, unsigned &Index,
352 InitListExpr *StructuredList,
353 unsigned &StructuredIndex);
354 bool CheckDesignatedInitializer(const InitializedEntity &Entity,
355 InitListExpr *IList, DesignatedInitExpr *DIE,
356 unsigned DesigIdx,
357 QualType &CurrentObjectType,
358 RecordDecl::field_iterator *NextField,
359 llvm::APSInt *NextElementIndex,
360 unsigned &Index,
361 InitListExpr *StructuredList,
362 unsigned &StructuredIndex,
363 bool FinishSubobjectInit,
364 bool TopLevelObject);
365 InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
366 QualType CurrentObjectType,
367 InitListExpr *StructuredList,
368 unsigned StructuredIndex,
369 SourceRange InitRange,
370 bool IsFullyOverwritten = false);
371 void UpdateStructuredListElement(InitListExpr *StructuredList,
372 unsigned &StructuredIndex,
373 Expr *expr);
374 InitListExpr *createInitListExpr(QualType CurrentObjectType,
375 SourceRange InitRange,
376 unsigned ExpectedNumInits);
377 int numArrayElements(QualType DeclType);
378 int numStructUnionElements(QualType DeclType);
379
380 ExprResult PerformEmptyInit(SourceLocation Loc,
381 const InitializedEntity &Entity);
382
383 /// Diagnose that OldInit (or part thereof) has been overridden by NewInit.
384 void diagnoseInitOverride(Expr *OldInit, SourceRange NewInitRange,
385 bool FullyOverwritten = true) {
386 // Overriding an initializer via a designator is valid with C99 designated
387 // initializers, but ill-formed with C++20 designated initializers.
388 unsigned DiagID = SemaRef.getLangOpts().CPlusPlus
389 ? diag::ext_initializer_overrides
390 : diag::warn_initializer_overrides;
391
392 if (InOverloadResolution && SemaRef.getLangOpts().CPlusPlus) {
393 // In overload resolution, we have to strictly enforce the rules, and so
394 // don't allow any overriding of prior initializers. This matters for a
395 // case such as:
396 //
397 // union U { int a, b; };
398 // struct S { int a, b; };
399 // void f(U), f(S);
400 //
401 // Here, f({.a = 1, .b = 2}) is required to call the struct overload. For
402 // consistency, we disallow all overriding of prior initializers in
403 // overload resolution, not only overriding of union members.
404 hadError = true;
405 } else if (OldInit->getType().isDestructedType() && !FullyOverwritten) {
406 // If we'll be keeping around the old initializer but overwriting part of
407 // the object it initialized, and that object is not trivially
408 // destructible, this can leak. Don't allow that, not even as an
409 // extension.
410 //
411 // FIXME: It might be reasonable to allow this in cases where the part of
412 // the initializer that we're overriding has trivial destruction.
413 DiagID = diag::err_initializer_overrides_destructed;
414 } else if (!OldInit->getSourceRange().isValid()) {
415 // We need to check on source range validity because the previous
416 // initializer does not have to be an explicit initializer. e.g.,
417 //
418 // struct P { int a, b; };
419 // struct PP { struct P p } l = { { .a = 2 }, .p.b = 3 };
420 //
421 // There is an overwrite taking place because the first braced initializer
422 // list "{ .a = 2 }" already provides value for .p.b (which is zero).
423 //
424 // Such overwrites are harmless, so we don't diagnose them. (Note that in
425 // C++, this cannot be reached unless we've already seen and diagnosed a
426 // different conformance issue, such as a mixture of designated and
427 // non-designated initializers or a multi-level designator.)
428 return;
429 }
430
431 if (!VerifyOnly) {
432 SemaRef.Diag(NewInitRange.getBegin(), DiagID)
433 << NewInitRange << FullyOverwritten << OldInit->getType();
434 SemaRef.Diag(OldInit->getBeginLoc(), diag::note_previous_initializer)
435 << (OldInit->HasSideEffects(SemaRef.Context) && FullyOverwritten)
436 << OldInit->getSourceRange();
437 }
438 }
439
440 // Explanation on the "FillWithNoInit" mode:
441 //
442 // Assume we have the following definitions (Case#1):
443 // struct P { char x[6][6]; } xp = { .x[1] = "bar" };
444 // struct PP { struct P lp; } l = { .lp = xp, .lp.x[1][2] = 'f' };
445 //
446 // l.lp.x[1][0..1] should not be filled with implicit initializers because the
447 // "base" initializer "xp" will provide values for them; l.lp.x[1] will be "baf".
448 //
449 // But if we have (Case#2):
450 // struct PP l = { .lp = xp, .lp.x[1] = { [2] = 'f' } };
451 //
452 // l.lp.x[1][0..1] are implicitly initialized and do not use values from the
453 // "base" initializer; l.lp.x[1] will be "\0\0f\0\0\0".
454 //
455 // To distinguish Case#1 from Case#2, and also to avoid leaving many "holes"
456 // in the InitListExpr, the "holes" in Case#1 are filled not with empty
457 // initializers but with special "NoInitExpr" place holders, which tells the
458 // CodeGen not to generate any initializers for these parts.
459 void FillInEmptyInitForBase(unsigned Init, const CXXBaseSpecifier &Base,
460 const InitializedEntity &ParentEntity,
461 InitListExpr *ILE, bool &RequiresSecondPass,
462 bool FillWithNoInit);
463 void FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
464 const InitializedEntity &ParentEntity,
465 InitListExpr *ILE, bool &RequiresSecondPass,
466 bool FillWithNoInit = false);
467 void FillInEmptyInitializations(const InitializedEntity &Entity,
468 InitListExpr *ILE, bool &RequiresSecondPass,
469 InitListExpr *OuterILE, unsigned OuterIndex,
470 bool FillWithNoInit = false);
471 bool CheckFlexibleArrayInit(const InitializedEntity &Entity,
472 Expr *InitExpr, FieldDecl *Field,
473 bool TopLevelObject);
474 void CheckEmptyInitializable(const InitializedEntity &Entity,
475 SourceLocation Loc);
476
477public:
478 InitListChecker(Sema &S, const InitializedEntity &Entity, InitListExpr *IL,
479 QualType &T, bool VerifyOnly, bool TreatUnavailableAsInvalid,
480 bool InOverloadResolution = false);
481 bool HadError() { return hadError; }
482
483 // Retrieves the fully-structured initializer list used for
484 // semantic analysis and code generation.
485 InitListExpr *getFullyStructuredList() const { return FullyStructuredList; }
486};
487
488} // end anonymous namespace
489
490ExprResult InitListChecker::PerformEmptyInit(SourceLocation Loc,
491 const InitializedEntity &Entity) {
492 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc,
493 true);
494 MultiExprArg SubInit;
495 Expr *InitExpr;
496 InitListExpr DummyInitList(SemaRef.Context, Loc, None, Loc);
497
498 // C++ [dcl.init.aggr]p7:
499 // If there are fewer initializer-clauses in the list than there are
500 // members in the aggregate, then each member not explicitly initialized
501 // ...
502 bool EmptyInitList = SemaRef.getLangOpts().CPlusPlus11 &&
503 Entity.getType()->getBaseElementTypeUnsafe()->isRecordType();
504 if (EmptyInitList) {
505 // C++1y / DR1070:
506 // shall be initialized [...] from an empty initializer list.
507 //
508 // We apply the resolution of this DR to C++11 but not C++98, since C++98
509 // does not have useful semantics for initialization from an init list.
510 // We treat this as copy-initialization, because aggregate initialization
511 // always performs copy-initialization on its elements.
512 //
513 // Only do this if we're initializing a class type, to avoid filling in
514 // the initializer list where possible.
515 InitExpr = VerifyOnly ? &DummyInitList : new (SemaRef.Context)
516 InitListExpr(SemaRef.Context, Loc, None, Loc);
517 InitExpr->setType(SemaRef.Context.VoidTy);
518 SubInit = InitExpr;
519 Kind = InitializationKind::CreateCopy(Loc, Loc);
520 } else {
521 // C++03:
522 // shall be value-initialized.
523 }
524
525 InitializationSequence InitSeq(SemaRef, Entity, Kind, SubInit);
526 // libstdc++4.6 marks the vector default constructor as explicit in
527 // _GLIBCXX_DEBUG mode, so recover using the C++03 logic in that case.
528 // stlport does so too. Look for std::__debug for libstdc++, and for
529 // std:: for stlport. This is effectively a compiler-side implementation of
530 // LWG2193.
531 if (!InitSeq && EmptyInitList && InitSeq.getFailureKind() ==
532 InitializationSequence::FK_ExplicitConstructor) {
533 OverloadCandidateSet::iterator Best;
534 OverloadingResult O =
535 InitSeq.getFailedCandidateSet()
536 .BestViableFunction(SemaRef, Kind.getLocation(), Best);
537 (void)O;
538 assert(O == OR_Success && "Inconsistent overload resolution")(static_cast <bool> (O == OR_Success && "Inconsistent overload resolution"
) ? void (0) : __assert_fail ("O == OR_Success && \"Inconsistent overload resolution\""
, "clang/lib/Sema/SemaInit.cpp", 538, __extension__ __PRETTY_FUNCTION__
))
;
539 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
540 CXXRecordDecl *R = CtorDecl->getParent();
541
542 if (CtorDecl->getMinRequiredArguments() == 0 &&
543 CtorDecl->isExplicit() && R->getDeclName() &&
544 SemaRef.SourceMgr.isInSystemHeader(CtorDecl->getLocation())) {
545 bool IsInStd = false;
546 for (NamespaceDecl *ND = dyn_cast<NamespaceDecl>(R->getDeclContext());
547 ND && !IsInStd; ND = dyn_cast<NamespaceDecl>(ND->getParent())) {
548 if (SemaRef.getStdNamespace()->InEnclosingNamespaceSetOf(ND))
549 IsInStd = true;
550 }
551
552 if (IsInStd && llvm::StringSwitch<bool>(R->getName())
553 .Cases("basic_string", "deque", "forward_list", true)
554 .Cases("list", "map", "multimap", "multiset", true)
555 .Cases("priority_queue", "queue", "set", "stack", true)
556 .Cases("unordered_map", "unordered_set", "vector", true)
557 .Default(false)) {
558 InitSeq.InitializeFrom(
559 SemaRef, Entity,
560 InitializationKind::CreateValue(Loc, Loc, Loc, true),
561 MultiExprArg(), /*TopLevelOfInitList=*/false,
562 TreatUnavailableAsInvalid);
563 // Emit a warning for this. System header warnings aren't shown
564 // by default, but people working on system headers should see it.
565 if (!VerifyOnly) {
566 SemaRef.Diag(CtorDecl->getLocation(),
567 diag::warn_invalid_initializer_from_system_header);
568 if (Entity.getKind() == InitializedEntity::EK_Member)
569 SemaRef.Diag(Entity.getDecl()->getLocation(),
570 diag::note_used_in_initialization_here);
571 else if (Entity.getKind() == InitializedEntity::EK_ArrayElement)
572 SemaRef.Diag(Loc, diag::note_used_in_initialization_here);
573 }
574 }
575 }
576 }
577 if (!InitSeq) {
578 if (!VerifyOnly) {
579 InitSeq.Diagnose(SemaRef, Entity, Kind, SubInit);
580 if (Entity.getKind() == InitializedEntity::EK_Member)
581 SemaRef.Diag(Entity.getDecl()->getLocation(),
582 diag::note_in_omitted_aggregate_initializer)
583 << /*field*/1 << Entity.getDecl();
584 else if (Entity.getKind() == InitializedEntity::EK_ArrayElement) {
585 bool IsTrailingArrayNewMember =
586 Entity.getParent() &&
587 Entity.getParent()->isVariableLengthArrayNew();
588 SemaRef.Diag(Loc, diag::note_in_omitted_aggregate_initializer)
589 << (IsTrailingArrayNewMember ? 2 : /*array element*/0)
590 << Entity.getElementIndex();
591 }
592 }
593 hadError = true;
594 return ExprError();
595 }
596
597 return VerifyOnly ? ExprResult()
598 : InitSeq.Perform(SemaRef, Entity, Kind, SubInit);
599}
600
601void InitListChecker::CheckEmptyInitializable(const InitializedEntity &Entity,
602 SourceLocation Loc) {
603 // If we're building a fully-structured list, we'll check this at the end
604 // once we know which elements are actually initialized. Otherwise, we know
605 // that there are no designators so we can just check now.
606 if (FullyStructuredList)
607 return;
608 PerformEmptyInit(Loc, Entity);
609}
610
611void InitListChecker::FillInEmptyInitForBase(
612 unsigned Init, const CXXBaseSpecifier &Base,
613 const InitializedEntity &ParentEntity, InitListExpr *ILE,
614 bool &RequiresSecondPass, bool FillWithNoInit) {
615 InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
616 SemaRef.Context, &Base, false, &ParentEntity);
617
618 if (Init >= ILE->getNumInits() || !ILE->getInit(Init)) {
619 ExprResult BaseInit = FillWithNoInit
620 ? new (SemaRef.Context) NoInitExpr(Base.getType())
621 : PerformEmptyInit(ILE->getEndLoc(), BaseEntity);
622 if (BaseInit.isInvalid()) {
623 hadError = true;
624 return;
625 }
626
627 if (!VerifyOnly) {
628 assert(Init < ILE->getNumInits() && "should have been expanded")(static_cast <bool> (Init < ILE->getNumInits() &&
"should have been expanded") ? void (0) : __assert_fail ("Init < ILE->getNumInits() && \"should have been expanded\""
, "clang/lib/Sema/SemaInit.cpp", 628, __extension__ __PRETTY_FUNCTION__
))
;
629 ILE->setInit(Init, BaseInit.getAs<Expr>());
630 }
631 } else if (InitListExpr *InnerILE =
632 dyn_cast<InitListExpr>(ILE->getInit(Init))) {
633 FillInEmptyInitializations(BaseEntity, InnerILE, RequiresSecondPass,
634 ILE, Init, FillWithNoInit);
635 } else if (DesignatedInitUpdateExpr *InnerDIUE =
636 dyn_cast<DesignatedInitUpdateExpr>(ILE->getInit(Init))) {
637 FillInEmptyInitializations(BaseEntity, InnerDIUE->getUpdater(),
638 RequiresSecondPass, ILE, Init,
639 /*FillWithNoInit =*/true);
640 }
641}
642
643void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
644 const InitializedEntity &ParentEntity,
645 InitListExpr *ILE,
646 bool &RequiresSecondPass,
647 bool FillWithNoInit) {
648 SourceLocation Loc = ILE->getEndLoc();
649 unsigned NumInits = ILE->getNumInits();
650 InitializedEntity MemberEntity
651 = InitializedEntity::InitializeMember(Field, &ParentEntity);
652
653 if (Init >= NumInits || !ILE->getInit(Init)) {
654 if (const RecordType *RType = ILE->getType()->getAs<RecordType>())
655 if (!RType->getDecl()->isUnion())
656 assert((Init < NumInits || VerifyOnly) &&(static_cast <bool> ((Init < NumInits || VerifyOnly)
&& "This ILE should have been expanded") ? void (0) :
__assert_fail ("(Init < NumInits || VerifyOnly) && \"This ILE should have been expanded\""
, "clang/lib/Sema/SemaInit.cpp", 657, __extension__ __PRETTY_FUNCTION__
))
657 "This ILE should have been expanded")(static_cast <bool> ((Init < NumInits || VerifyOnly)
&& "This ILE should have been expanded") ? void (0) :
__assert_fail ("(Init < NumInits || VerifyOnly) && \"This ILE should have been expanded\""
, "clang/lib/Sema/SemaInit.cpp", 657, __extension__ __PRETTY_FUNCTION__
))
;
658
659 if (FillWithNoInit) {
660 assert(!VerifyOnly && "should not fill with no-init in verify-only mode")(static_cast <bool> (!VerifyOnly && "should not fill with no-init in verify-only mode"
) ? void (0) : __assert_fail ("!VerifyOnly && \"should not fill with no-init in verify-only mode\""
, "clang/lib/Sema/SemaInit.cpp", 660, __extension__ __PRETTY_FUNCTION__
))
;
661 Expr *Filler = new (SemaRef.Context) NoInitExpr(Field->getType());
662 if (Init < NumInits)
663 ILE->setInit(Init, Filler);
664 else
665 ILE->updateInit(SemaRef.Context, Init, Filler);
666 return;
667 }
668 // C++1y [dcl.init.aggr]p7:
669 // If there are fewer initializer-clauses in the list than there are
670 // members in the aggregate, then each member not explicitly initialized
671 // shall be initialized from its brace-or-equal-initializer [...]
672 if (Field->hasInClassInitializer()) {
673 if (VerifyOnly)
674 return;
675
676 ExprResult DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field);
677 if (DIE.isInvalid()) {
678 hadError = true;
679 return;
680 }
681 SemaRef.checkInitializerLifetime(MemberEntity, DIE.get());
682 if (Init < NumInits)
683 ILE->setInit(Init, DIE.get());
684 else {
685 ILE->updateInit(SemaRef.Context, Init, DIE.get());
686 RequiresSecondPass = true;
687 }
688 return;
689 }
690
691 if (Field->getType()->isReferenceType()) {
692 if (!VerifyOnly) {
693 // C++ [dcl.init.aggr]p9:
694 // If an incomplete or empty initializer-list leaves a
695 // member of reference type uninitialized, the program is
696 // ill-formed.
697 SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized)
698 << Field->getType()
699 << ILE->getSyntacticForm()->getSourceRange();
700 SemaRef.Diag(Field->getLocation(),
701 diag::note_uninit_reference_member);
702 }
703 hadError = true;
704 return;
705 }
706
707 ExprResult MemberInit = PerformEmptyInit(Loc, MemberEntity);
708 if (MemberInit.isInvalid()) {
709 hadError = true;
710 return;
711 }
712
713 if (hadError || VerifyOnly) {
714 // Do nothing
715 } else if (Init < NumInits) {
716 ILE->setInit(Init, MemberInit.getAs<Expr>());
717 } else if (!isa<ImplicitValueInitExpr>(MemberInit.get())) {
718 // Empty initialization requires a constructor call, so
719 // extend the initializer list to include the constructor
720 // call and make a note that we'll need to take another pass
721 // through the initializer list.
722 ILE->updateInit(SemaRef.Context, Init, MemberInit.getAs<Expr>());
723 RequiresSecondPass = true;
724 }
725 } else if (InitListExpr *InnerILE
726 = dyn_cast<InitListExpr>(ILE->getInit(Init))) {
727 FillInEmptyInitializations(MemberEntity, InnerILE,
728 RequiresSecondPass, ILE, Init, FillWithNoInit);
729 } else if (DesignatedInitUpdateExpr *InnerDIUE =
730 dyn_cast<DesignatedInitUpdateExpr>(ILE->getInit(Init))) {
731 FillInEmptyInitializations(MemberEntity, InnerDIUE->getUpdater(),
732 RequiresSecondPass, ILE, Init,
733 /*FillWithNoInit =*/true);
734 }
735}
736
737/// Recursively replaces NULL values within the given initializer list
738/// with expressions that perform value-initialization of the
739/// appropriate type, and finish off the InitListExpr formation.
740void
741InitListChecker::FillInEmptyInitializations(const InitializedEntity &Entity,
742 InitListExpr *ILE,
743 bool &RequiresSecondPass,
744 InitListExpr *OuterILE,
745 unsigned OuterIndex,
746 bool FillWithNoInit) {
747 assert((ILE->getType() != SemaRef.Context.VoidTy) &&(static_cast <bool> ((ILE->getType() != SemaRef.Context
.VoidTy) && "Should not have void type") ? void (0) :
__assert_fail ("(ILE->getType() != SemaRef.Context.VoidTy) && \"Should not have void type\""
, "clang/lib/Sema/SemaInit.cpp", 748, __extension__ __PRETTY_FUNCTION__
))
748 "Should not have void type")(static_cast <bool> ((ILE->getType() != SemaRef.Context
.VoidTy) && "Should not have void type") ? void (0) :
__assert_fail ("(ILE->getType() != SemaRef.Context.VoidTy) && \"Should not have void type\""
, "clang/lib/Sema/SemaInit.cpp", 748, __extension__ __PRETTY_FUNCTION__
))
;
749
750 // We don't need to do any checks when just filling NoInitExprs; that can't
751 // fail.
752 if (FillWithNoInit && VerifyOnly)
753 return;
754
755 // If this is a nested initializer list, we might have changed its contents
756 // (and therefore some of its properties, such as instantiation-dependence)
757 // while filling it in. Inform the outer initializer list so that its state
758 // can be updated to match.
759 // FIXME: We should fully build the inner initializers before constructing
760 // the outer InitListExpr instead of mutating AST nodes after they have
761 // been used as subexpressions of other nodes.
762 struct UpdateOuterILEWithUpdatedInit {
763 InitListExpr *Outer;
764 unsigned OuterIndex;
765 ~UpdateOuterILEWithUpdatedInit() {
766 if (Outer)
767 Outer->setInit(OuterIndex, Outer->getInit(OuterIndex));
768 }
769 } UpdateOuterRAII = {OuterILE, OuterIndex};
770
771 // A transparent ILE is not performing aggregate initialization and should
772 // not be filled in.
773 if (ILE->isTransparent())
774 return;
775
776 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
777 const RecordDecl *RDecl = RType->getDecl();
778 if (RDecl->isUnion() && ILE->getInitializedFieldInUnion())
779 FillInEmptyInitForField(0, ILE->getInitializedFieldInUnion(),
780 Entity, ILE, RequiresSecondPass, FillWithNoInit);
781 else if (RDecl->isUnion() && isa<CXXRecordDecl>(RDecl) &&
782 cast<CXXRecordDecl>(RDecl)->hasInClassInitializer()) {
783 for (auto *Field : RDecl->fields()) {
784 if (Field->hasInClassInitializer()) {
785 FillInEmptyInitForField(0, Field, Entity, ILE, RequiresSecondPass,
786 FillWithNoInit);
787 break;
788 }
789 }
790 } else {
791 // The fields beyond ILE->getNumInits() are default initialized, so in
792 // order to leave them uninitialized, the ILE is expanded and the extra
793 // fields are then filled with NoInitExpr.
794 unsigned NumElems = numStructUnionElements(ILE->getType());
795 if (RDecl->hasFlexibleArrayMember())
796 ++NumElems;
797 if (!VerifyOnly && ILE->getNumInits() < NumElems)
798 ILE->resizeInits(SemaRef.Context, NumElems);
799
800 unsigned Init = 0;
801
802 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RDecl)) {
803 for (auto &Base : CXXRD->bases()) {
804 if (hadError)
805 return;
806
807 FillInEmptyInitForBase(Init, Base, Entity, ILE, RequiresSecondPass,
808 FillWithNoInit);
809 ++Init;
810 }
811 }
812
813 for (auto *Field : RDecl->fields()) {
814 if (Field->isUnnamedBitfield())
815 continue;
816
817 if (hadError)
818 return;
819
820 FillInEmptyInitForField(Init, Field, Entity, ILE, RequiresSecondPass,
821 FillWithNoInit);
822 if (hadError)
823 return;
824
825 ++Init;
826
827 // Only look at the first initialization of a union.
828 if (RDecl->isUnion())
829 break;
830 }
831 }
832
833 return;
834 }
835
836 QualType ElementType;
837
838 InitializedEntity ElementEntity = Entity;
839 unsigned NumInits = ILE->getNumInits();
840 unsigned NumElements = NumInits;
841 if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) {
842 ElementType = AType->getElementType();
843 if (const auto *CAType = dyn_cast<ConstantArrayType>(AType))
844 NumElements = CAType->getSize().getZExtValue();
845 // For an array new with an unknown bound, ask for one additional element
846 // in order to populate the array filler.
847 if (Entity.isVariableLengthArrayNew())
848 ++NumElements;
849 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
850 0, Entity);
851 } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) {
852 ElementType = VType->getElementType();
853 NumElements = VType->getNumElements();
854 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
855 0, Entity);
856 } else
857 ElementType = ILE->getType();
858
859 bool SkipEmptyInitChecks = false;
860 for (unsigned Init = 0; Init != NumElements; ++Init) {
861 if (hadError)
862 return;
863
864 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement ||
865 ElementEntity.getKind() == InitializedEntity::EK_VectorElement)
866 ElementEntity.setElementIndex(Init);
867
868 if (Init >= NumInits && (ILE->hasArrayFiller() || SkipEmptyInitChecks))
869 return;
870
871 Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : nullptr);
872 if (!InitExpr && Init < NumInits && ILE->hasArrayFiller())
873 ILE->setInit(Init, ILE->getArrayFiller());
874 else if (!InitExpr && !ILE->hasArrayFiller()) {
875 // In VerifyOnly mode, there's no point performing empty initialization
876 // more than once.
877 if (SkipEmptyInitChecks)
878 continue;
879
880 Expr *Filler = nullptr;
881
882 if (FillWithNoInit)
883 Filler = new (SemaRef.Context) NoInitExpr(ElementType);
884 else {
885 ExprResult ElementInit =
886 PerformEmptyInit(ILE->getEndLoc(), ElementEntity);
887 if (ElementInit.isInvalid()) {
888 hadError = true;
889 return;
890 }
891
892 Filler = ElementInit.getAs<Expr>();
893 }
894
895 if (hadError) {
896 // Do nothing
897 } else if (VerifyOnly) {
898 SkipEmptyInitChecks = true;
899 } else if (Init < NumInits) {
900 // For arrays, just set the expression used for value-initialization
901 // of the "holes" in the array.
902 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement)
903 ILE->setArrayFiller(Filler);
904 else
905 ILE->setInit(Init, Filler);
906 } else {
907 // For arrays, just set the expression used for value-initialization
908 // of the rest of elements and exit.
909 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) {
910 ILE->setArrayFiller(Filler);
911 return;
912 }
913
914 if (!isa<ImplicitValueInitExpr>(Filler) && !isa<NoInitExpr>(Filler)) {
915 // Empty initialization requires a constructor call, so
916 // extend the initializer list to include the constructor
917 // call and make a note that we'll need to take another pass
918 // through the initializer list.
919 ILE->updateInit(SemaRef.Context, Init, Filler);
920 RequiresSecondPass = true;
921 }
922 }
923 } else if (InitListExpr *InnerILE
924 = dyn_cast_or_null<InitListExpr>(InitExpr)) {
925 FillInEmptyInitializations(ElementEntity, InnerILE, RequiresSecondPass,
926 ILE, Init, FillWithNoInit);
927 } else if (DesignatedInitUpdateExpr *InnerDIUE =
928 dyn_cast_or_null<DesignatedInitUpdateExpr>(InitExpr)) {
929 FillInEmptyInitializations(ElementEntity, InnerDIUE->getUpdater(),
930 RequiresSecondPass, ILE, Init,
931 /*FillWithNoInit =*/true);
932 }
933 }
934}
935
936static bool hasAnyDesignatedInits(const InitListExpr *IL) {
937 for (const Stmt *Init : *IL)
938 if (Init && isa<DesignatedInitExpr>(Init))
939 return true;
940 return false;
941}
942
943InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity,
944 InitListExpr *IL, QualType &T, bool VerifyOnly,
945 bool TreatUnavailableAsInvalid,
946 bool InOverloadResolution)
947 : SemaRef(S), VerifyOnly(VerifyOnly),
948 TreatUnavailableAsInvalid(TreatUnavailableAsInvalid),
949 InOverloadResolution(InOverloadResolution) {
950 if (!VerifyOnly || hasAnyDesignatedInits(IL)) {
951 FullyStructuredList =
952 createInitListExpr(T, IL->getSourceRange(), IL->getNumInits());
953
954 // FIXME: Check that IL isn't already the semantic form of some other
955 // InitListExpr. If it is, we'd create a broken AST.
956 if (!VerifyOnly)
957 FullyStructuredList->setSyntacticForm(IL);
958 }
959
960 CheckExplicitInitList(Entity, IL, T, FullyStructuredList,
961 /*TopLevelObject=*/true);
962
963 if (!hadError && FullyStructuredList) {
964 bool RequiresSecondPass = false;
965 FillInEmptyInitializations(Entity, FullyStructuredList, RequiresSecondPass,
966 /*OuterILE=*/nullptr, /*OuterIndex=*/0);
967 if (RequiresSecondPass && !hadError)
968 FillInEmptyInitializations(Entity, FullyStructuredList,
969 RequiresSecondPass, nullptr, 0);
970 }
971 if (hadError && FullyStructuredList)
972 FullyStructuredList->markError();
973}
974
975int InitListChecker::numArrayElements(QualType DeclType) {
976 // FIXME: use a proper constant
977 int maxElements = 0x7FFFFFFF;
978 if (const ConstantArrayType *CAT =
979 SemaRef.Context.getAsConstantArrayType(DeclType)) {
980 maxElements = static_cast<int>(CAT->getSize().getZExtValue());
981 }
982 return maxElements;
983}
984
985int InitListChecker::numStructUnionElements(QualType DeclType) {
986 RecordDecl *structDecl = DeclType->castAs<RecordType>()->getDecl();
987 int InitializableMembers = 0;
988 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(structDecl))
989 InitializableMembers += CXXRD->getNumBases();
990 for (const auto *Field : structDecl->fields())
991 if (!Field->isUnnamedBitfield())
992 ++InitializableMembers;
993
994 if (structDecl->isUnion())
995 return std::min(InitializableMembers, 1);
996 return InitializableMembers - structDecl->hasFlexibleArrayMember();
997}
998
999/// Determine whether Entity is an entity for which it is idiomatic to elide
1000/// the braces in aggregate initialization.
1001static bool isIdiomaticBraceElisionEntity(const InitializedEntity &Entity) {
1002 // Recursive initialization of the one and only field within an aggregate
1003 // class is considered idiomatic. This case arises in particular for
1004 // initialization of std::array, where the C++ standard suggests the idiom of
1005 //
1006 // std::array<T, N> arr = {1, 2, 3};
1007 //
1008 // (where std::array is an aggregate struct containing a single array field.
1009
1010 if (!Entity.getParent())
1011 return false;
1012
1013 // Allows elide brace initialization for aggregates with empty base.
1014 if (Entity.getKind() == InitializedEntity::EK_Base) {
1015 auto *ParentRD =
1016 Entity.getParent()->getType()->castAs<RecordType>()->getDecl();
1017 CXXRecordDecl *CXXRD = cast<CXXRecordDecl>(ParentRD);
1018 return CXXRD->getNumBases() == 1 && CXXRD->field_empty();
1019 }
1020
1021 // Allow brace elision if the only subobject is a field.
1022 if (Entity.getKind() == InitializedEntity::EK_Member) {
1023 auto *ParentRD =
1024 Entity.getParent()->getType()->castAs<RecordType>()->getDecl();
1025 if (CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(ParentRD)) {
1026 if (CXXRD->getNumBases()) {
1027 return false;
1028 }
1029 }
1030 auto FieldIt = ParentRD->field_begin();
1031 assert(FieldIt != ParentRD->field_end() &&(static_cast <bool> (FieldIt != ParentRD->field_end(
) && "no fields but have initializer for member?") ? void
(0) : __assert_fail ("FieldIt != ParentRD->field_end() && \"no fields but have initializer for member?\""
, "clang/lib/Sema/SemaInit.cpp", 1032, __extension__ __PRETTY_FUNCTION__
))
1032 "no fields but have initializer for member?")(static_cast <bool> (FieldIt != ParentRD->field_end(
) && "no fields but have initializer for member?") ? void
(0) : __assert_fail ("FieldIt != ParentRD->field_end() && \"no fields but have initializer for member?\""
, "clang/lib/Sema/SemaInit.cpp", 1032, __extension__ __PRETTY_FUNCTION__
))
;
1033 return ++FieldIt == ParentRD->field_end();
1034 }
1035
1036 return false;
1037}
1038
1039/// Check whether the range of the initializer \p ParentIList from element
1040/// \p Index onwards can be used to initialize an object of type \p T. Update
1041/// \p Index to indicate how many elements of the list were consumed.
1042///
1043/// This also fills in \p StructuredList, from element \p StructuredIndex
1044/// onwards, with the fully-braced, desugared form of the initialization.
1045void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity,
1046 InitListExpr *ParentIList,
1047 QualType T, unsigned &Index,
1048 InitListExpr *StructuredList,
1049 unsigned &StructuredIndex) {
1050 int maxElements = 0;
1051
1052 if (T->isArrayType())
1053 maxElements = numArrayElements(T);
1054 else if (T->isRecordType())
1055 maxElements = numStructUnionElements(T);
1056 else if (T->isVectorType())
1057 maxElements = T->castAs<VectorType>()->getNumElements();
1058 else
1059 llvm_unreachable("CheckImplicitInitList(): Illegal type")::llvm::llvm_unreachable_internal("CheckImplicitInitList(): Illegal type"
, "clang/lib/Sema/SemaInit.cpp", 1059)
;
1060
1061 if (maxElements == 0) {
1062 if (!VerifyOnly)
1063 SemaRef.Diag(ParentIList->getInit(Index)->getBeginLoc(),
1064 diag::err_implicit_empty_initializer);
1065 ++Index;
1066 hadError = true;
1067 return;
1068 }
1069
1070 // Build a structured initializer list corresponding to this subobject.
1071 InitListExpr *StructuredSubobjectInitList = getStructuredSubobjectInit(
1072 ParentIList, Index, T, StructuredList, StructuredIndex,
1073 SourceRange(ParentIList->getInit(Index)->getBeginLoc(),
1074 ParentIList->getSourceRange().getEnd()));
1075 unsigned StructuredSubobjectInitIndex = 0;
1076
1077 // Check the element types and build the structural subobject.
1078 unsigned StartIndex = Index;
1079 CheckListElementTypes(Entity, ParentIList, T,
1080 /*SubobjectIsDesignatorContext=*/false, Index,
1081 StructuredSubobjectInitList,
1082 StructuredSubobjectInitIndex);
1083
1084 if (StructuredSubobjectInitList) {
1085 StructuredSubobjectInitList->setType(T);
1086
1087 unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1);
1088 // Update the structured sub-object initializer so that it's ending
1089 // range corresponds with the end of the last initializer it used.
1090 if (EndIndex < ParentIList->getNumInits() &&
1091 ParentIList->getInit(EndIndex)) {
1092 SourceLocation EndLoc
1093 = ParentIList->getInit(EndIndex)->getSourceRange().getEnd();
1094 StructuredSubobjectInitList->setRBraceLoc(EndLoc);
1095 }
1096
1097 // Complain about missing braces.
1098 if (!VerifyOnly && (T->isArrayType() || T->isRecordType()) &&
1099 !ParentIList->isIdiomaticZeroInitializer(SemaRef.getLangOpts()) &&
1100 !isIdiomaticBraceElisionEntity(Entity)) {
1101 SemaRef.Diag(StructuredSubobjectInitList->getBeginLoc(),
1102 diag::warn_missing_braces)
1103 << StructuredSubobjectInitList->getSourceRange()
1104 << FixItHint::CreateInsertion(
1105 StructuredSubobjectInitList->getBeginLoc(), "{")
1106 << FixItHint::CreateInsertion(
1107 SemaRef.getLocForEndOfToken(
1108 StructuredSubobjectInitList->getEndLoc()),
1109 "}");
1110 }
1111
1112 // Warn if this type won't be an aggregate in future versions of C++.
1113 auto *CXXRD = T->getAsCXXRecordDecl();
1114 if (!VerifyOnly && CXXRD && CXXRD->hasUserDeclaredConstructor()) {
1115 SemaRef.Diag(StructuredSubobjectInitList->getBeginLoc(),
1116 diag::warn_cxx20_compat_aggregate_init_with_ctors)
1117 << StructuredSubobjectInitList->getSourceRange() << T;
1118 }
1119 }
1120}
1121
1122/// Warn that \p Entity was of scalar type and was initialized by a
1123/// single-element braced initializer list.
1124static void warnBracedScalarInit(Sema &S, const InitializedEntity &Entity,
1125 SourceRange Braces) {
1126 // Don't warn during template instantiation. If the initialization was
1127 // non-dependent, we warned during the initial parse; otherwise, the
1128 // type might not be scalar in some uses of the template.
1129 if (S.inTemplateInstantiation())
1130 return;
1131
1132 unsigned DiagID = 0;
1133
1134 switch (Entity.getKind()) {
1135 case InitializedEntity::EK_VectorElement:
1136 case InitializedEntity::EK_ComplexElement:
1137 case InitializedEntity::EK_ArrayElement:
1138 case InitializedEntity::EK_Parameter:
1139 case InitializedEntity::EK_Parameter_CF_Audited:
1140 case InitializedEntity::EK_TemplateParameter:
1141 case InitializedEntity::EK_Result:
1142 // Extra braces here are suspicious.
1143 DiagID = diag::warn_braces_around_init;
1144 break;
1145
1146 case InitializedEntity::EK_Member:
1147 // Warn on aggregate initialization but not on ctor init list or
1148 // default member initializer.
1149 if (Entity.getParent())
1150 DiagID = diag::warn_braces_around_init;
1151 break;
1152
1153 case InitializedEntity::EK_Variable:
1154 case InitializedEntity::EK_LambdaCapture:
1155 // No warning, might be direct-list-initialization.
1156 // FIXME: Should we warn for copy-list-initialization in these cases?
1157 break;
1158
1159 case InitializedEntity::EK_New:
1160 case InitializedEntity::EK_Temporary:
1161 case InitializedEntity::EK_CompoundLiteralInit:
1162 // No warning, braces are part of the syntax of the underlying construct.
1163 break;
1164
1165 case InitializedEntity::EK_RelatedResult:
1166 // No warning, we already warned when initializing the result.
1167 break;
1168
1169 case InitializedEntity::EK_Exception:
1170 case InitializedEntity::EK_Base:
1171 case InitializedEntity::EK_Delegating:
1172 case InitializedEntity::EK_BlockElement:
1173 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
1174 case InitializedEntity::EK_Binding:
1175 case InitializedEntity::EK_StmtExprResult:
1176 llvm_unreachable("unexpected braced scalar init")::llvm::llvm_unreachable_internal("unexpected braced scalar init"
, "clang/lib/Sema/SemaInit.cpp", 1176)
;
1177 }
1178
1179 if (DiagID) {
1180 S.Diag(Braces.getBegin(), DiagID)
1181 << Entity.getType()->isSizelessBuiltinType() << Braces
1182 << FixItHint::CreateRemoval(Braces.getBegin())
1183 << FixItHint::CreateRemoval(Braces.getEnd());
1184 }
1185}
1186
1187/// Check whether the initializer \p IList (that was written with explicit
1188/// braces) can be used to initialize an object of type \p T.
1189///
1190/// This also fills in \p StructuredList with the fully-braced, desugared
1191/// form of the initialization.
1192void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity,
1193 InitListExpr *IList, QualType &T,
1194 InitListExpr *StructuredList,
1195 bool TopLevelObject) {
1196 unsigned Index = 0, StructuredIndex = 0;
1197 CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true,
1198 Index, StructuredList, StructuredIndex, TopLevelObject);
1199 if (StructuredList) {
1200 QualType ExprTy = T;
1201 if (!ExprTy->isArrayType())
1202 ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context);
1203 if (!VerifyOnly)
1204 IList->setType(ExprTy);
1205 StructuredList->setType(ExprTy);
1206 }
1207 if (hadError)
1208 return;
1209
1210 // Don't complain for incomplete types, since we'll get an error elsewhere.
1211 if (Index < IList->getNumInits() && !T->isIncompleteType()) {
1212 // We have leftover initializers
1213 bool ExtraInitsIsError = SemaRef.getLangOpts().CPlusPlus ||
1214 (SemaRef.getLangOpts().OpenCL && T->isVectorType());
1215 hadError = ExtraInitsIsError;
1216 if (VerifyOnly) {
1217 return;
1218 } else if (StructuredIndex == 1 &&
1219 IsStringInit(StructuredList->getInit(0), T, SemaRef.Context) ==
1220 SIF_None) {
1221 unsigned DK =
1222 ExtraInitsIsError
1223 ? diag::err_excess_initializers_in_char_array_initializer
1224 : diag::ext_excess_initializers_in_char_array_initializer;
1225 SemaRef.Diag(IList->getInit(Index)->getBeginLoc(), DK)
1226 << IList->getInit(Index)->getSourceRange();
1227 } else if (T->isSizelessBuiltinType()) {
1228 unsigned DK = ExtraInitsIsError
1229 ? diag::err_excess_initializers_for_sizeless_type
1230 : diag::ext_excess_initializers_for_sizeless_type;
1231 SemaRef.Diag(IList->getInit(Index)->getBeginLoc(), DK)
1232 << T << IList->getInit(Index)->getSourceRange();
1233 } else {
1234 int initKind = T->isArrayType() ? 0 :
1235 T->isVectorType() ? 1 :
1236 T->isScalarType() ? 2 :
1237 T->isUnionType() ? 3 :
1238 4;
1239
1240 unsigned DK = ExtraInitsIsError ? diag::err_excess_initializers
1241 : diag::ext_excess_initializers;
1242 SemaRef.Diag(IList->getInit(Index)->getBeginLoc(), DK)
1243 << initKind << IList->getInit(Index)->getSourceRange();
1244 }
1245 }
1246
1247 if (!VerifyOnly) {
1248 if (T->isScalarType() && IList->getNumInits() == 1 &&
1249 !isa<InitListExpr>(IList->getInit(0)))
1250 warnBracedScalarInit(SemaRef, Entity, IList->getSourceRange());
1251
1252 // Warn if this is a class type that won't be an aggregate in future
1253 // versions of C++.
1254 auto *CXXRD = T->getAsCXXRecordDecl();
1255 if (CXXRD && CXXRD->hasUserDeclaredConstructor()) {
1256 // Don't warn if there's an equivalent default constructor that would be
1257 // used instead.
1258 bool HasEquivCtor = false;
1259 if (IList->getNumInits() == 0) {
1260 auto *CD = SemaRef.LookupDefaultConstructor(CXXRD);
1261 HasEquivCtor = CD && !CD->isDeleted();
1262 }
1263
1264 if (!HasEquivCtor) {
1265 SemaRef.Diag(IList->getBeginLoc(),
1266 diag::warn_cxx20_compat_aggregate_init_with_ctors)
1267 << IList->getSourceRange() << T;
1268 }
1269 }
1270 }
1271}
1272
1273void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity,
1274 InitListExpr *IList,
1275 QualType &DeclType,
1276 bool SubobjectIsDesignatorContext,
1277 unsigned &Index,
1278 InitListExpr *StructuredList,
1279 unsigned &StructuredIndex,
1280 bool TopLevelObject) {
1281 if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) {
1282 // Explicitly braced initializer for complex type can be real+imaginary
1283 // parts.
1284 CheckComplexType(Entity, IList, DeclType, Index,
1285 StructuredList, StructuredIndex);
1286 } else if (DeclType->isScalarType()) {
1287 CheckScalarType(Entity, IList, DeclType, Index,
1288 StructuredList, StructuredIndex);
1289 } else if (DeclType->isVectorType()) {
1290 CheckVectorType(Entity, IList, DeclType, Index,
1291 StructuredList, StructuredIndex);
1292 } else if (DeclType->isRecordType()) {
1293 assert(DeclType->isAggregateType() &&(static_cast <bool> (DeclType->isAggregateType() &&
"non-aggregate records should be handed in CheckSubElementType"
) ? void (0) : __assert_fail ("DeclType->isAggregateType() && \"non-aggregate records should be handed in CheckSubElementType\""
, "clang/lib/Sema/SemaInit.cpp", 1294, __extension__ __PRETTY_FUNCTION__
))
1294 "non-aggregate records should be handed in CheckSubElementType")(static_cast <bool> (DeclType->isAggregateType() &&
"non-aggregate records should be handed in CheckSubElementType"
) ? void (0) : __assert_fail ("DeclType->isAggregateType() && \"non-aggregate records should be handed in CheckSubElementType\""
, "clang/lib/Sema/SemaInit.cpp", 1294, __extension__ __PRETTY_FUNCTION__
))
;
1295 RecordDecl *RD = DeclType->castAs<RecordType>()->getDecl();
1296 auto Bases =
1297 CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
1298 CXXRecordDecl::base_class_iterator());
1299 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD))
1300 Bases = CXXRD->bases();
1301 CheckStructUnionTypes(Entity, IList, DeclType, Bases, RD->field_begin(),
1302 SubobjectIsDesignatorContext, Index, StructuredList,
1303 StructuredIndex, TopLevelObject);
1304 } else if (DeclType->isArrayType()) {
1305 llvm::APSInt Zero(
1306 SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()),
1307 false);
1308 CheckArrayType(Entity, IList, DeclType, Zero,
1309 SubobjectIsDesignatorContext, Index,
1310 StructuredList, StructuredIndex);
1311 } else if (DeclType->isVoidType() || DeclType->isFunctionType()) {
1312 // This type is invalid, issue a diagnostic.
1313 ++Index;
1314 if (!VerifyOnly)
1315 SemaRef.Diag(IList->getBeginLoc(), diag::err_illegal_initializer_type)
1316 << DeclType;
1317 hadError = true;
1318 } else if (DeclType->isReferenceType()) {
1319 CheckReferenceType(Entity, IList, DeclType, Index,
1320 StructuredList, StructuredIndex);
1321 } else if (DeclType->isObjCObjectType()) {
1322 if (!VerifyOnly)
1323 SemaRef.Diag(IList->getBeginLoc(), diag::err_init_objc_class) << DeclType;
1324 hadError = true;
1325 } else if (DeclType->isOCLIntelSubgroupAVCType() ||
1326 DeclType->isSizelessBuiltinType()) {
1327 // Checks for scalar type are sufficient for these types too.
1328 CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
1329 StructuredIndex);
1330 } else {
1331 if (!VerifyOnly)
1332 SemaRef.Diag(IList->getBeginLoc(), diag::err_illegal_initializer_type)
1333 << DeclType;
1334 hadError = true;
1335 }
1336}
1337
1338void InitListChecker::CheckSubElementType(const InitializedEntity &Entity,
1339 InitListExpr *IList,
1340 QualType ElemType,
1341 unsigned &Index,
1342 InitListExpr *StructuredList,
1343 unsigned &StructuredIndex,
1344 bool DirectlyDesignated) {
1345 Expr *expr = IList->getInit(Index);
1346
1347 if (ElemType->isReferenceType())
1348 return CheckReferenceType(Entity, IList, ElemType, Index,
1349 StructuredList, StructuredIndex);
1350
1351 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) {
1352 if (SubInitList->getNumInits() == 1 &&
1353 IsStringInit(SubInitList->getInit(0), ElemType, SemaRef.Context) ==
1354 SIF_None) {
1355 // FIXME: It would be more faithful and no less correct to include an
1356 // InitListExpr in the semantic form of the initializer list in this case.
1357 expr = SubInitList->getInit(0);
1358 }
1359 // Nested aggregate initialization and C++ initialization are handled later.
1360 } else if (isa<ImplicitValueInitExpr>(expr)) {
1361 // This happens during template instantiation when we see an InitListExpr
1362 // that we've already checked once.
1363 assert(SemaRef.Context.hasSameType(expr->getType(), ElemType) &&(static_cast <bool> (SemaRef.Context.hasSameType(expr->
getType(), ElemType) && "found implicit initialization for the wrong type"
) ? void (0) : __assert_fail ("SemaRef.Context.hasSameType(expr->getType(), ElemType) && \"found implicit initialization for the wrong type\""
, "clang/lib/Sema/SemaInit.cpp", 1364, __extension__ __PRETTY_FUNCTION__
))
1364 "found implicit initialization for the wrong type")(static_cast <bool> (SemaRef.Context.hasSameType(expr->
getType(), ElemType) && "found implicit initialization for the wrong type"
) ? void (0) : __assert_fail ("SemaRef.Context.hasSameType(expr->getType(), ElemType) && \"found implicit initialization for the wrong type\""
, "clang/lib/Sema/SemaInit.cpp", 1364, __extension__ __PRETTY_FUNCTION__
))
;
1365 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1366 ++Index;
1367 return;
1368 }
1369
1370 if (SemaRef.getLangOpts().CPlusPlus || isa<InitListExpr>(expr)) {
1371 // C++ [dcl.init.aggr]p2:
1372 // Each member is copy-initialized from the corresponding
1373 // initializer-clause.
1374
1375 // FIXME: Better EqualLoc?
1376 InitializationKind Kind =
1377 InitializationKind::CreateCopy(expr->getBeginLoc(), SourceLocation());
1378
1379 // Vector elements can be initialized from other vectors in which case
1380 // we need initialization entity with a type of a vector (and not a vector
1381 // element!) initializing multiple vector elements.
1382 auto TmpEntity =
1383 (ElemType->isExtVectorType() && !Entity.getType()->isExtVectorType())
1384 ? InitializedEntity::InitializeTemporary(ElemType)
1385 : Entity;
1386
1387 InitializationSequence Seq(SemaRef, TmpEntity, Kind, expr,
1388 /*TopLevelOfInitList*/ true);
1389
1390 // C++14 [dcl.init.aggr]p13:
1391 // If the assignment-expression can initialize a member, the member is
1392 // initialized. Otherwise [...] brace elision is assumed
1393 //
1394 // Brace elision is never performed if the element is not an
1395 // assignment-expression.
1396 if (Seq || isa<InitListExpr>(expr)) {
1397 if (!VerifyOnly) {
1398 ExprResult Result = Seq.Perform(SemaRef, TmpEntity, Kind, expr);
1399 if (Result.isInvalid())
1400 hadError = true;
1401
1402 UpdateStructuredListElement(StructuredList, StructuredIndex,
1403 Result.getAs<Expr>());
1404 } else if (!Seq) {
1405 hadError = true;
1406 } else if (StructuredList) {
1407 UpdateStructuredListElement(StructuredList, StructuredIndex,
1408 getDummyInit());
1409 }
1410 ++Index;
1411 return;
1412 }
1413
1414 // Fall through for subaggregate initialization
1415 } else if (ElemType->isScalarType() || ElemType->isAtomicType()) {
1416 // FIXME: Need to handle atomic aggregate types with implicit init lists.
1417 return CheckScalarType(Entity, IList, ElemType, Index,
1418 StructuredList, StructuredIndex);
1419 } else if (const ArrayType *arrayType =
1420 SemaRef.Context.getAsArrayType(ElemType)) {
1421 // arrayType can be incomplete if we're initializing a flexible
1422 // array member. There's nothing we can do with the completed
1423 // type here, though.
1424
1425 if (IsStringInit(expr, arrayType, SemaRef.Context) == SIF_None) {
1426 // FIXME: Should we do this checking in verify-only mode?
1427 if (!VerifyOnly)
1428 CheckStringInit(expr, ElemType, arrayType, SemaRef);
1429 if (StructuredList)
1430 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1431 ++Index;
1432 return;
1433 }
1434
1435 // Fall through for subaggregate initialization.
1436
1437 } else {
1438 assert((ElemType->isRecordType() || ElemType->isVectorType() ||(static_cast <bool> ((ElemType->isRecordType() || ElemType
->isVectorType() || ElemType->isOpenCLSpecificType()) &&
"Unexpected type") ? void (0) : __assert_fail ("(ElemType->isRecordType() || ElemType->isVectorType() || ElemType->isOpenCLSpecificType()) && \"Unexpected type\""
, "clang/lib/Sema/SemaInit.cpp", 1439, __extension__ __PRETTY_FUNCTION__
))
1439 ElemType->isOpenCLSpecificType()) && "Unexpected type")(static_cast <bool> ((ElemType->isRecordType() || ElemType
->isVectorType() || ElemType->isOpenCLSpecificType()) &&
"Unexpected type") ? void (0) : __assert_fail ("(ElemType->isRecordType() || ElemType->isVectorType() || ElemType->isOpenCLSpecificType()) && \"Unexpected type\""
, "clang/lib/Sema/SemaInit.cpp", 1439, __extension__ __PRETTY_FUNCTION__
))
;
1440
1441 // C99 6.7.8p13:
1442 //
1443 // The initializer for a structure or union object that has
1444 // automatic storage duration shall be either an initializer
1445 // list as described below, or a single expression that has
1446 // compatible structure or union type. In the latter case, the
1447 // initial value of the object, including unnamed members, is
1448 // that of the expression.
1449 ExprResult ExprRes = expr;
1450 if (SemaRef.CheckSingleAssignmentConstraints(
1451 ElemType, ExprRes, !VerifyOnly) != Sema::Incompatible) {
1452 if (ExprRes.isInvalid())
1453 hadError = true;
1454 else {
1455 ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.get());
1456 if (ExprRes.isInvalid())
1457 hadError = true;
1458 }
1459 UpdateStructuredListElement(StructuredList, StructuredIndex,
1460 ExprRes.getAs<Expr>());
1461 ++Index;
1462 return;
1463 }
1464 ExprRes.get();
1465 // Fall through for subaggregate initialization
1466 }
1467
1468 // C++ [dcl.init.aggr]p12:
1469 //
1470 // [...] Otherwise, if the member is itself a non-empty
1471 // subaggregate, brace elision is assumed and the initializer is
1472 // considered for the initialization of the first member of
1473 // the subaggregate.
1474 // OpenCL vector initializer is handled elsewhere.
1475 if ((!SemaRef.getLangOpts().OpenCL && ElemType->isVectorType()) ||
1476 ElemType->isAggregateType()) {
1477 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList,
1478 StructuredIndex);
1479 ++StructuredIndex;
1480
1481 // In C++20, brace elision is not permitted for a designated initializer.
1482 if (DirectlyDesignated && SemaRef.getLangOpts().CPlusPlus && !hadError) {
1483 if (InOverloadResolution)
1484 hadError = true;
1485 if (!VerifyOnly) {
1486 SemaRef.Diag(expr->getBeginLoc(),
1487 diag::ext_designated_init_brace_elision)
1488 << expr->getSourceRange()
1489 << FixItHint::CreateInsertion(expr->getBeginLoc(), "{")
1490 << FixItHint::CreateInsertion(
1491 SemaRef.getLocForEndOfToken(expr->getEndLoc()), "}");
1492 }
1493 }
1494 } else {
1495 if (!VerifyOnly) {
1496 // We cannot initialize this element, so let PerformCopyInitialization
1497 // produce the appropriate diagnostic. We already checked that this
1498 // initialization will fail.
1499 ExprResult Copy =
1500 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), expr,
1501 /*TopLevelOfInitList=*/true);
1502 (void)Copy;
1503 assert(Copy.isInvalid() &&(static_cast <bool> (Copy.isInvalid() && "expected non-aggregate initialization to fail"
) ? void (0) : __assert_fail ("Copy.isInvalid() && \"expected non-aggregate initialization to fail\""
, "clang/lib/Sema/SemaInit.cpp", 1504, __extension__ __PRETTY_FUNCTION__
))
1504 "expected non-aggregate initialization to fail")(static_cast <bool> (Copy.isInvalid() && "expected non-aggregate initialization to fail"
) ? void (0) : __assert_fail ("Copy.isInvalid() && \"expected non-aggregate initialization to fail\""
, "clang/lib/Sema/SemaInit.cpp", 1504, __extension__ __PRETTY_FUNCTION__
))
;
1505 }
1506 hadError = true;
1507 ++Index;
1508 ++StructuredIndex;
1509 }
1510}
1511
1512void InitListChecker::CheckComplexType(const InitializedEntity &Entity,
1513 InitListExpr *IList, QualType DeclType,
1514 unsigned &Index,
1515 InitListExpr *StructuredList,
1516 unsigned &StructuredIndex) {
1517 assert(Index == 0 && "Index in explicit init list must be zero")(static_cast <bool> (Index == 0 && "Index in explicit init list must be zero"
) ? void (0) : __assert_fail ("Index == 0 && \"Index in explicit init list must be zero\""
, "clang/lib/Sema/SemaInit.cpp", 1517, __extension__ __PRETTY_FUNCTION__
))
;
1518
1519 // As an extension, clang supports complex initializers, which initialize
1520 // a complex number component-wise. When an explicit initializer list for
1521 // a complex number contains two two initializers, this extension kicks in:
1522 // it exepcts the initializer list to contain two elements convertible to
1523 // the element type of the complex type. The first element initializes
1524 // the real part, and the second element intitializes the imaginary part.
1525
1526 if (IList->getNumInits() != 2)
1527 return CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
1528 StructuredIndex);
1529
1530 // This is an extension in C. (The builtin _Complex type does not exist
1531 // in the C++ standard.)
1532 if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly)
1533 SemaRef.Diag(IList->getBeginLoc(), diag::ext_complex_component_init)
1534 << IList->getSourceRange();
1535
1536 // Initialize the complex number.
1537 QualType elementType = DeclType->castAs<ComplexType>()->getElementType();
1538 InitializedEntity ElementEntity =
1539 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1540
1541 for (unsigned i = 0; i < 2; ++i) {
1542 ElementEntity.setElementIndex(Index);
1543 CheckSubElementType(ElementEntity, IList, elementType, Index,
1544 StructuredList, StructuredIndex);
1545 }
1546}
1547
1548void InitListChecker::CheckScalarType(const InitializedEntity &Entity,
1549 InitListExpr *IList, QualType DeclType,
1550 unsigned &Index,
1551 InitListExpr *StructuredList,
1552 unsigned &StructuredIndex) {
1553 if (Index >= IList->getNumInits()) {
1554 if (!VerifyOnly) {
1555 if (DeclType->isSizelessBuiltinType())
1556 SemaRef.Diag(IList->getBeginLoc(),
1557 SemaRef.getLangOpts().CPlusPlus11
1558 ? diag::warn_cxx98_compat_empty_sizeless_initializer
1559 : diag::err_empty_sizeless_initializer)
1560 << DeclType << IList->getSourceRange();
1561 else
1562 SemaRef.Diag(IList->getBeginLoc(),
1563 SemaRef.getLangOpts().CPlusPlus11
1564 ? diag::warn_cxx98_compat_empty_scalar_initializer
1565 : diag::err_empty_scalar_initializer)
1566 << IList->getSourceRange();
1567 }
1568 hadError = !SemaRef.getLangOpts().CPlusPlus11;
1569 ++Index;
1570 ++StructuredIndex;
1571 return;
1572 }
1573
1574 Expr *expr = IList->getInit(Index);
1575 if (InitListExpr *SubIList = dyn_cast<InitListExpr>(expr)) {
1576 // FIXME: This is invalid, and accepting it causes overload resolution
1577 // to pick the wrong overload in some corner cases.
1578 if (!VerifyOnly)
1579 SemaRef.Diag(SubIList->getBeginLoc(), diag::ext_many_braces_around_init)
1580 << DeclType->isSizelessBuiltinType() << SubIList->getSourceRange();
1581
1582 CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList,
1583 StructuredIndex);
1584 return;
1585 } else if (isa<DesignatedInitExpr>(expr)) {
1586 if (!VerifyOnly)
1587 SemaRef.Diag(expr->getBeginLoc(),
1588 diag::err_designator_for_scalar_or_sizeless_init)
1589 << DeclType->isSizelessBuiltinType() << DeclType
1590 << expr->getSourceRange();
1591 hadError = true;
1592 ++Index;
1593 ++StructuredIndex;
1594 return;
1595 }
1596
1597 ExprResult Result;
1598 if (VerifyOnly) {
1599 if (SemaRef.CanPerformCopyInitialization(Entity, expr))
1600 Result = getDummyInit();
1601 else
1602 Result = ExprError();
1603 } else {
1604 Result =
1605 SemaRef.PerformCopyInitialization(Entity, expr->getBeginLoc(), expr,
1606 /*TopLevelOfInitList=*/true);
1607 }
1608
1609 Expr *ResultExpr = nullptr;
1610
1611 if (Result.isInvalid())
1612 hadError = true; // types weren't compatible.
1613 else {
1614 ResultExpr = Result.getAs<Expr>();
1615
1616 if (ResultExpr != expr && !VerifyOnly) {
1617 // The type was promoted, update initializer list.
1618 // FIXME: Why are we updating the syntactic init list?
1619 IList->setInit(Index, ResultExpr);
1620 }
1621 }
1622 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr);
1623 ++Index;
1624}
1625
1626void InitListChecker::CheckReferenceType(const InitializedEntity &Entity,
1627 InitListExpr *IList, QualType DeclType,
1628 unsigned &Index,
1629 InitListExpr *StructuredList,
1630 unsigned &StructuredIndex) {
1631 if (Index >= IList->getNumInits()) {
1632 // FIXME: It would be wonderful if we could point at the actual member. In
1633 // general, it would be useful to pass location information down the stack,
1634 // so that we know the location (or decl) of the "current object" being
1635 // initialized.
1636 if (!VerifyOnly)
1637 SemaRef.Diag(IList->getBeginLoc(),
1638 diag::err_init_reference_member_uninitialized)
1639 << DeclType << IList->getSourceRange();
1640 hadError = true;
1641 ++Index;
1642 ++StructuredIndex;
1643 return;
1644 }
1645
1646 Expr *expr = IList->getInit(Index);
1647 if (isa<InitListExpr>(expr) && !SemaRef.getLangOpts().CPlusPlus11) {
1648 if (!VerifyOnly)
1649 SemaRef.Diag(IList->getBeginLoc(), diag::err_init_non_aggr_init_list)
1650 << DeclType << IList->getSourceRange();
1651 hadError = true;
1652 ++Index;
1653 ++StructuredIndex;
1654 return;
1655 }
1656
1657 ExprResult Result;
1658 if (VerifyOnly) {
1659 if (SemaRef.CanPerformCopyInitialization(Entity,expr))
1660 Result = getDummyInit();
1661 else
1662 Result = ExprError();
1663 } else {
1664 Result =
1665 SemaRef.PerformCopyInitialization(Entity, expr->getBeginLoc(), expr,
1666 /*TopLevelOfInitList=*/true);
1667 }
1668
1669 if (Result.isInvalid())
1670 hadError = true;
1671
1672 expr = Result.getAs<Expr>();
1673 // FIXME: Why are we updating the syntactic init list?
1674 if (!VerifyOnly && expr)
1675 IList->setInit(Index, expr);
1676
1677 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1678 ++Index;
1679}
1680
1681void InitListChecker::CheckVectorType(const InitializedEntity &Entity,
1682 InitListExpr *IList, QualType DeclType,
1683 unsigned &Index,
1684 InitListExpr *StructuredList,
1685 unsigned &StructuredIndex) {
1686 const VectorType *VT = DeclType->castAs<VectorType>();
1687 unsigned maxElements = VT->getNumElements();
1688 unsigned numEltsInit = 0;
1689 QualType elementType = VT->getElementType();
1690
1691 if (Index >= IList->getNumInits()) {
1692 // Make sure the element type can be value-initialized.
1693 CheckEmptyInitializable(
1694 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
1695 IList->getEndLoc());
1696 return;
1697 }
1698
1699 if (!SemaRef.getLangOpts().OpenCL && !SemaRef.getLangOpts().HLSL ) {
1700 // If the initializing element is a vector, try to copy-initialize
1701 // instead of breaking it apart (which is doomed to failure anyway).
1702 Expr *Init = IList->getInit(Index);
1703 if (!isa<InitListExpr>(Init) && Init->getType()->isVectorType()) {
1704 ExprResult Result;
1705 if (VerifyOnly) {
1706 if (SemaRef.CanPerformCopyInitialization(Entity, Init))
1707 Result = getDummyInit();
1708 else
1709 Result = ExprError();
1710 } else {
1711 Result =
1712 SemaRef.PerformCopyInitialization(Entity, Init->getBeginLoc(), Init,
1713 /*TopLevelOfInitList=*/true);
1714 }
1715
1716 Expr *ResultExpr = nullptr;
1717 if (Result.isInvalid())
1718 hadError = true; // types weren't compatible.
1719 else {
1720 ResultExpr = Result.getAs<Expr>();
1721
1722 if (ResultExpr != Init && !VerifyOnly) {
1723 // The type was promoted, update initializer list.
1724 // FIXME: Why are we updating the syntactic init list?
1725 IList->setInit(Index, ResultExpr);
1726 }
1727 }
1728 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr);
1729 ++Index;
1730 return;
1731 }
1732
1733 InitializedEntity ElementEntity =
1734 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1735
1736 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) {
1737 // Don't attempt to go past the end of the init list
1738 if (Index >= IList->getNumInits()) {
1739 CheckEmptyInitializable(ElementEntity, IList->getEndLoc());
1740 break;
1741 }
1742
1743 ElementEntity.setElementIndex(Index);
1744 CheckSubElementType(ElementEntity, IList, elementType, Index,
1745 StructuredList, StructuredIndex);
1746 }
1747
1748 if (VerifyOnly)
1749 return;
1750
1751 bool isBigEndian = SemaRef.Context.getTargetInfo().isBigEndian();
1752 const VectorType *T = Entity.getType()->castAs<VectorType>();
1753 if (isBigEndian && (T->getVectorKind() == VectorType::NeonVector ||
1754 T->getVectorKind() == VectorType::NeonPolyVector)) {
1755 // The ability to use vector initializer lists is a GNU vector extension
1756 // and is unrelated to the NEON intrinsics in arm_neon.h. On little
1757 // endian machines it works fine, however on big endian machines it
1758 // exhibits surprising behaviour:
1759 //
1760 // uint32x2_t x = {42, 64};
1761 // return vget_lane_u32(x, 0); // Will return 64.
1762 //
1763 // Because of this, explicitly call out that it is non-portable.
1764 //
1765 SemaRef.Diag(IList->getBeginLoc(),
1766 diag::warn_neon_vector_initializer_non_portable);
1767
1768 const char *typeCode;
1769 unsigned typeSize = SemaRef.Context.getTypeSize(elementType);
1770
1771 if (elementType->isFloatingType())
1772 typeCode = "f";
1773 else if (elementType->isSignedIntegerType())
1774 typeCode = "s";
1775 else if (elementType->isUnsignedIntegerType())
1776 typeCode = "u";
1777 else
1778 llvm_unreachable("Invalid element type!")::llvm::llvm_unreachable_internal("Invalid element type!", "clang/lib/Sema/SemaInit.cpp"
, 1778)
;
1779
1780 SemaRef.Diag(IList->getBeginLoc(),
1781 SemaRef.Context.getTypeSize(VT) > 64
1782 ? diag::note_neon_vector_initializer_non_portable_q
1783 : diag::note_neon_vector_initializer_non_portable)
1784 << typeCode << typeSize;
1785 }
1786
1787 return;
1788 }
1789
1790 InitializedEntity ElementEntity =
1791 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1792
1793 // OpenCL and HLSL initializers allow vectors to be constructed from vectors.
1794 for (unsigned i = 0; i < maxElements; ++i) {
1795 // Don't attempt to go past the end of the init list
1796 if (Index >= IList->getNumInits())
1797 break;
1798
1799 ElementEntity.setElementIndex(Index);
1800
1801 QualType IType = IList->getInit(Index)->getType();
1802 if (!IType->isVectorType()) {
1803 CheckSubElementType(ElementEntity, IList, elementType, Index,
1804 StructuredList, StructuredIndex);
1805 ++numEltsInit;
1806 } else {
1807 QualType VecType;
1808 const VectorType *IVT = IType->castAs<VectorType>();
1809 unsigned numIElts = IVT->getNumElements();
1810
1811 if (IType->isExtVectorType())
1812 VecType = SemaRef.Context.getExtVectorType(elementType, numIElts);
1813 else
1814 VecType = SemaRef.Context.getVectorType(elementType, numIElts,
1815 IVT->getVectorKind());
1816 CheckSubElementType(ElementEntity, IList, VecType, Index,
1817 StructuredList, StructuredIndex);
1818 numEltsInit += numIElts;
1819 }
1820 }
1821
1822 // OpenCL and HLSL require all elements to be initialized.
1823 if (numEltsInit != maxElements) {
1824 if (!VerifyOnly)
1825 SemaRef.Diag(IList->getBeginLoc(),
1826 diag::err_vector_incorrect_num_initializers)
1827 << (numEltsInit < maxElements) << maxElements << numEltsInit;
1828 hadError = true;
1829 }
1830}
1831
1832/// Check if the type of a class element has an accessible destructor, and marks
1833/// it referenced. Returns true if we shouldn't form a reference to the
1834/// destructor.
1835///
1836/// Aggregate initialization requires a class element's destructor be
1837/// accessible per 11.6.1 [dcl.init.aggr]:
1838///
1839/// The destructor for each element of class type is potentially invoked
1840/// (15.4 [class.dtor]) from the context where the aggregate initialization
1841/// occurs.
1842static bool checkDestructorReference(QualType ElementType, SourceLocation Loc,
1843 Sema &SemaRef) {
1844 auto *CXXRD = ElementType->getAsCXXRecordDecl();
1845 if (!CXXRD)
1846 return false;
1847
1848 CXXDestructorDecl *Destructor = SemaRef.LookupDestructor(CXXRD);
1849 SemaRef.CheckDestructorAccess(Loc, Destructor,
1850 SemaRef.PDiag(diag::err_access_dtor_temp)
1851 << ElementType);
1852 SemaRef.MarkFunctionReferenced(Loc, Destructor);
1853 return SemaRef.DiagnoseUseOfDecl(Destructor, Loc);
1854}
1855
1856void InitListChecker::CheckArrayType(const InitializedEntity &Entity,
1857 InitListExpr *IList, QualType &DeclType,
1858 llvm::APSInt elementIndex,
1859 bool SubobjectIsDesignatorContext,
1860 unsigned &Index,
1861 InitListExpr *StructuredList,
1862 unsigned &StructuredIndex) {
1863 const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType);
1864
1865 if (!VerifyOnly) {
1866 if (checkDestructorReference(arrayType->getElementType(),
1867 IList->getEndLoc(), SemaRef)) {
1868 hadError = true;
1869 return;
1870 }
1871 }
1872
1873 // Check for the special-case of initializing an array with a string.
1874 if (Index < IList->getNumInits()) {
1875 if (IsStringInit(IList->getInit(Index), arrayType, SemaRef.Context) ==
1876 SIF_None) {
1877 // We place the string literal directly into the resulting
1878 // initializer list. This is the only place where the structure
1879 // of the structured initializer list doesn't match exactly,
1880 // because doing so would involve allocating one character
1881 // constant for each string.
1882 // FIXME: Should we do these checks in verify-only mode too?
1883 if (!VerifyOnly)
1884 CheckStringInit(IList->getInit(Index), DeclType, arrayType, SemaRef);
1885 if (StructuredList) {
1886 UpdateStructuredListElement(StructuredList, StructuredIndex,
1887 IList->getInit(Index));
1888 StructuredList->resizeInits(SemaRef.Context, StructuredIndex);
1889 }
1890 ++Index;
1891 return;
1892 }
1893 }
1894 if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(arrayType)) {
1895 // Check for VLAs; in standard C it would be possible to check this
1896 // earlier, but I don't know where clang accepts VLAs (gcc accepts
1897 // them in all sorts of strange places).
1898 if (!VerifyOnly)
1899 SemaRef.Diag(VAT->getSizeExpr()->getBeginLoc(),
1900 diag::err_variable_object_no_init)
1901 << VAT->getSizeExpr()->getSourceRange();
1902 hadError = true;
1903 ++Index;
1904 ++StructuredIndex;
1905 return;
1906 }
1907
1908 // We might know the maximum number of elements in advance.
1909 llvm::APSInt maxElements(elementIndex.getBitWidth(),
1910 elementIndex.isUnsigned());
1911 bool maxElementsKnown = false;
1912 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(arrayType)) {
1913 maxElements = CAT->getSize();
1914 elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth());
1915 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1916 maxElementsKnown = true;
1917 }
1918
1919 QualType elementType = arrayType->getElementType();
1920 while (Index < IList->getNumInits()) {
1921 Expr *Init = IList->getInit(Index);
1922 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
1923 // If we're not the subobject that matches up with the '{' for
1924 // the designator, we shouldn't be handling the
1925 // designator. Return immediately.
1926 if (!SubobjectIsDesignatorContext)
1927 return;
1928
1929 // Handle this designated initializer. elementIndex will be
1930 // updated to be the next array element we'll initialize.
1931 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
1932 DeclType, nullptr, &elementIndex, Index,
1933 StructuredList, StructuredIndex, true,
1934 false)) {
1935 hadError = true;
1936 continue;
1937 }
1938
1939 if (elementIndex.getBitWidth() > maxElements.getBitWidth())
1940 maxElements = maxElements.extend(elementIndex.getBitWidth());
1941 else if (elementIndex.getBitWidth() < maxElements.getBitWidth())
1942 elementIndex = elementIndex.extend(maxElements.getBitWidth());
1943 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1944
1945 // If the array is of incomplete type, keep track of the number of
1946 // elements in the initializer.
1947 if (!maxElementsKnown && elementIndex > maxElements)
1948 maxElements = elementIndex;
1949
1950 continue;
1951 }
1952
1953 // If we know the maximum number of elements, and we've already
1954 // hit it, stop consuming elements in the initializer list.
1955 if (maxElementsKnown && elementIndex == maxElements)
1956 break;
1957
1958 InitializedEntity ElementEntity =
1959 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex,
1960 Entity);
1961 // Check this element.
1962 CheckSubElementType(ElementEntity, IList, elementType, Index,
1963 StructuredList, StructuredIndex);
1964 ++elementIndex;
1965
1966 // If the array is of incomplete type, keep track of the number of
1967 // elements in the initializer.
1968 if (!maxElementsKnown && elementIndex > maxElements)
1969 maxElements = elementIndex;
1970 }
1971 if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) {
1972 // If this is an incomplete array type, the actual type needs to
1973 // be calculated here.
1974 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned());
1975 if (maxElements == Zero && !Entity.isVariableLengthArrayNew()) {
1976 // Sizing an array implicitly to zero is not allowed by ISO C,
1977 // but is supported by GNU.
1978 SemaRef.Diag(IList->getBeginLoc(), diag::ext_typecheck_zero_array_size);
1979 }
1980
1981 DeclType = SemaRef.Context.getConstantArrayType(
1982 elementType, maxElements, nullptr, ArrayType::Normal, 0);
1983 }
1984 if (!hadError) {
1985 // If there are any members of the array that get value-initialized, check
1986 // that is possible. That happens if we know the bound and don't have
1987 // enough elements, or if we're performing an array new with an unknown
1988 // bound.
1989 if ((maxElementsKnown && elementIndex < maxElements) ||
1990 Entity.isVariableLengthArrayNew())
1991 CheckEmptyInitializable(
1992 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
1993 IList->getEndLoc());
1994 }
1995}
1996
1997bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity,
1998 Expr *InitExpr,
1999 FieldDecl *Field,
2000 bool TopLevelObject) {
2001 // Handle GNU flexible array initializers.
2002 unsigned FlexArrayDiag;
2003 if (isa<InitListExpr>(InitExpr) &&
2004 cast<InitListExpr>(InitExpr)->getNumInits() == 0) {
2005 // Empty flexible array init always allowed as an extension
2006 FlexArrayDiag = diag::ext_flexible_array_init;
2007 } else if (!TopLevelObject) {
2008 // Disallow flexible array init on non-top-level object
2009 FlexArrayDiag = diag::err_flexible_array_init;
2010 } else if (Entity.getKind() != InitializedEntity::EK_Variable) {
2011 // Disallow flexible array init on anything which is not a variable.
2012 FlexArrayDiag = diag::err_flexible_array_init;
2013 } else if (cast<VarDecl>(Entity.getDecl())->hasLocalStorage()) {
2014 // Disallow flexible array init on local variables.
2015 FlexArrayDiag = diag::err_flexible_array_init;
2016 } else {
2017 // Allow other cases.
2018 FlexArrayDiag = diag::ext_flexible_array_init;
2019 }
2020
2021 if (!VerifyOnly) {
2022 SemaRef.Diag(InitExpr->getBeginLoc(), FlexArrayDiag)
2023 << InitExpr->getBeginLoc();
2024 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2025 << Field;
2026 }
2027
2028 return FlexArrayDiag != diag::ext_flexible_array_init;
2029}
2030
2031void InitListChecker::CheckStructUnionTypes(
2032 const InitializedEntity &Entity, InitListExpr *IList, QualType DeclType,
2033 CXXRecordDecl::base_class_range Bases, RecordDecl::field_iterator Field,
2034 bool SubobjectIsDesignatorContext, unsigned &Index,
2035 InitListExpr *StructuredList, unsigned &StructuredIndex,
2036 bool TopLevelObject) {
2037 RecordDecl *structDecl = DeclType->castAs<RecordType>()->getDecl();
2038
2039 // If the record is invalid, some of it's members are invalid. To avoid
2040 // confusion, we forgo checking the initializer for the entire record.
2041 if (structDecl->isInvalidDecl()) {
2042 // Assume it was supposed to consume a single initializer.
2043 ++Index;
2044 hadError = true;
2045 return;
2046 }
2047
2048 if (DeclType->isUnionType() && IList->getNumInits() == 0) {
2049 RecordDecl *RD = DeclType->castAs<RecordType>()->getDecl();
2050
2051 if (!VerifyOnly)
2052 for (FieldDecl *FD : RD->fields()) {
2053 QualType ET = SemaRef.Context.getBaseElementType(FD->getType());
2054 if (checkDestructorReference(ET, IList->getEndLoc(), SemaRef)) {
2055 hadError = true;
2056 return;
2057 }
2058 }
2059
2060 // If there's a default initializer, use it.
2061 if (isa<CXXRecordDecl>(RD) &&
2062 cast<CXXRecordDecl>(RD)->hasInClassInitializer()) {
2063 if (!StructuredList)
2064 return;
2065 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
2066 Field != FieldEnd; ++Field) {
2067 if (Field->hasInClassInitializer()) {
2068 StructuredList->setInitializedFieldInUnion(*Field);
2069 // FIXME: Actually build a CXXDefaultInitExpr?
2070 return;
2071 }
2072 }
2073 }
2074
2075 // Value-initialize the first member of the union that isn't an unnamed
2076 // bitfield.
2077 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
2078 Field != FieldEnd; ++Field) {
2079 if (!Field->isUnnamedBitfield()) {
2080 CheckEmptyInitializable(
2081 InitializedEntity::InitializeMember(*Field, &Entity),
2082 IList->getEndLoc());
2083 if (StructuredList)
2084 StructuredList->setInitializedFieldInUnion(*Field);
2085 break;
2086 }
2087 }
2088 return;
2089 }
2090
2091 bool InitializedSomething = false;
2092
2093 // If we have any base classes, they are initialized prior to the fields.
2094 for (auto &Base : Bases) {
2095 Expr *Init = Index < IList->getNumInits() ? IList->getInit(Index) : nullptr;
2096
2097 // Designated inits always initialize fields, so if we see one, all
2098 // remaining base classes have no explicit initializer.
2099 if (Init && isa<DesignatedInitExpr>(Init))
2100 Init = nullptr;
2101
2102 SourceLocation InitLoc = Init ? Init->getBeginLoc() : IList->getEndLoc();
2103 InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
2104 SemaRef.Context, &Base, false, &Entity);
2105 if (Init) {
2106 CheckSubElementType(BaseEntity, IList, Base.getType(), Index,
2107 StructuredList, StructuredIndex);
2108 InitializedSomething = true;
2109 } else {
2110 CheckEmptyInitializable(BaseEntity, InitLoc);
2111 }
2112
2113 if (!VerifyOnly)
2114 if (checkDestructorReference(Base.getType(), InitLoc, SemaRef)) {
2115 hadError = true;
2116 return;
2117 }
2118 }
2119
2120 // If structDecl is a forward declaration, this loop won't do
2121 // anything except look at designated initializers; That's okay,
2122 // because an error should get printed out elsewhere. It might be
2123 // worthwhile to skip over the rest of the initializer, though.
2124 RecordDecl *RD = DeclType->castAs<RecordType>()->getDecl();
2125 RecordDecl::field_iterator FieldEnd = RD->field_end();
2126 size_t NumRecordDecls = llvm::count_if(RD->decls(), [&](const Decl *D) {
2127 return isa<FieldDecl>(D) || isa<RecordDecl>(D);
2128 });
2129 bool CheckForMissingFields =
2130 !IList->isIdiomaticZeroInitializer(SemaRef.getLangOpts());
2131 bool HasDesignatedInit = false;
2132
2133 while (Index < IList->getNumInits()) {
2134 Expr *Init = IList->getInit(Index);
2135 SourceLocation InitLoc = Init->getBeginLoc();
2136
2137 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
2138 // If we're not the subobject that matches up with the '{' for
2139 // the designator, we shouldn't be handling the
2140 // designator. Return immediately.
2141 if (!SubobjectIsDesignatorContext)
2142 return;
2143
2144 HasDesignatedInit = true;
2145
2146 // Handle this designated initializer. Field will be updated to
2147 // the next field that we'll be initializing.
2148 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
2149 DeclType, &Field, nullptr, Index,
2150 StructuredList, StructuredIndex,
2151 true, TopLevelObject))
2152 hadError = true;
2153 else if (!VerifyOnly) {
2154 // Find the field named by the designated initializer.
2155 RecordDecl::field_iterator F = RD->field_begin();
2156 while (std::next(F) != Field)
2157 ++F;
2158 QualType ET = SemaRef.Context.getBaseElementType(F->getType());
2159 if (checkDestructorReference(ET, InitLoc, SemaRef)) {
2160 hadError = true;
2161 return;
2162 }
2163 }
2164
2165 InitializedSomething = true;
2166
2167 // Disable check for missing fields when designators are used.
2168 // This matches gcc behaviour.
2169 CheckForMissingFields = false;
2170 continue;
2171 }
2172
2173 // Check if this is an initializer of forms:
2174 //
2175 // struct foo f = {};
2176 // struct foo g = {0};
2177 //
2178 // These are okay for randomized structures. [C99 6.7.8p19]
2179 //
2180 // Also, if there is only one element in the structure, we allow something
2181 // like this, because it's really not randomized in the tranditional sense.
2182 //
2183 // struct foo h = {bar};
2184 auto IsZeroInitializer = [&](const Expr *I) {
2185 if (IList->getNumInits() == 1) {
2186 if (NumRecordDecls == 1)
2187 return true;
2188 if (const auto *IL = dyn_cast<IntegerLiteral>(I))
2189 return IL->getValue().isZero();
2190 }
2191 return false;
2192 };
2193
2194 // Don't allow non-designated initializers on randomized structures.
2195 if (RD->isRandomized() && !IsZeroInitializer(Init)) {
2196 if (!VerifyOnly)
2197 SemaRef.Diag(InitLoc, diag::err_non_designated_init_used);
2198 hadError = true;
2199 break;
2200 }
2201
2202 if (Field == FieldEnd) {
2203 // We've run out of fields. We're done.
2204 break;
2205 }
2206
2207 // We've already initialized a member of a union. We're done.
2208 if (InitializedSomething && DeclType->isUnionType())
2209 break;
2210
2211 // If we've hit the flexible array member at the end, we're done.
2212 if (Field->getType()->isIncompleteArrayType())
2213 break;
2214
2215 if (Field->isUnnamedBitfield()) {
2216 // Don't initialize unnamed bitfields, e.g. "int : 20;"
2217 ++Field;
2218 continue;
2219 }
2220
2221 // Make sure we can use this declaration.
2222 bool InvalidUse;
2223 if (VerifyOnly)
2224 InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
2225 else
2226 InvalidUse = SemaRef.DiagnoseUseOfDecl(
2227 *Field, IList->getInit(Index)->getBeginLoc());
2228 if (InvalidUse) {
2229 ++Index;
2230 ++Field;
2231 hadError = true;
2232 continue;
2233 }
2234
2235 if (!VerifyOnly) {
2236 QualType ET = SemaRef.Context.getBaseElementType(Field->getType());
2237 if (checkDestructorReference(ET, InitLoc, SemaRef)) {
2238 hadError = true;
2239 return;
2240 }
2241 }
2242
2243 InitializedEntity MemberEntity =
2244 InitializedEntity::InitializeMember(*Field, &Entity);
2245 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2246 StructuredList, StructuredIndex);
2247 InitializedSomething = true;
2248
2249 if (DeclType->isUnionType() && StructuredList) {
2250 // Initialize the first field within the union.
2251 StructuredList->setInitializedFieldInUnion(*Field);
2252 }
2253
2254 ++Field;
2255 }
2256
2257 // Emit warnings for missing struct field initializers.
2258 if (!VerifyOnly && InitializedSomething && CheckForMissingFields &&
2259 Field != FieldEnd && !Field->getType()->isIncompleteArrayType() &&
2260 !DeclType->isUnionType()) {
2261 // It is possible we have one or more unnamed bitfields remaining.
2262 // Find first (if any) named field and emit warning.
2263 for (RecordDecl::field_iterator it = Field, end = RD->field_end();
2264 it != end; ++it) {
2265 if (!it->isUnnamedBitfield() && !it->hasInClassInitializer()) {
2266 SemaRef.Diag(IList->getSourceRange().getEnd(),
2267 diag::warn_missing_field_initializers) << *it;
2268 break;
2269 }
2270 }
2271 }
2272
2273 // Check that any remaining fields can be value-initialized if we're not
2274 // building a structured list. (If we are, we'll check this later.)
2275 if (!StructuredList && Field != FieldEnd && !DeclType->isUnionType() &&
2276 !Field->getType()->isIncompleteArrayType()) {
2277 for (; Field != FieldEnd && !hadError; ++Field) {
2278 if (!Field->isUnnamedBitfield() && !Field->hasInClassInitializer())
2279 CheckEmptyInitializable(
2280 InitializedEntity::InitializeMember(*Field, &Entity),
2281 IList->getEndLoc());
2282 }
2283 }
2284
2285 // Check that the types of the remaining fields have accessible destructors.
2286 if (!VerifyOnly) {
2287 // If the initializer expression has a designated initializer, check the
2288 // elements for which a designated initializer is not provided too.
2289 RecordDecl::field_iterator I = HasDesignatedInit ? RD->field_begin()
2290 : Field;
2291 for (RecordDecl::field_iterator E = RD->field_end(); I != E; ++I) {
2292 QualType ET = SemaRef.Context.getBaseElementType(I->getType());
2293 if (checkDestructorReference(ET, IList->getEndLoc(), SemaRef)) {
2294 hadError = true;
2295 return;
2296 }
2297 }
2298 }
2299
2300 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() ||
2301 Index >= IList->getNumInits())
2302 return;
2303
2304 if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field,
2305 TopLevelObject)) {
2306 hadError = true;
2307 ++Index;
2308 return;
2309 }
2310
2311 InitializedEntity MemberEntity =
2312 InitializedEntity::InitializeMember(*Field, &Entity);
2313
2314 if (isa<InitListExpr>(IList->getInit(Index)))
2315 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2316 StructuredList, StructuredIndex);
2317 else
2318 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index,
2319 StructuredList, StructuredIndex);
2320}
2321
2322/// Expand a field designator that refers to a member of an
2323/// anonymous struct or union into a series of field designators that
2324/// refers to the field within the appropriate subobject.
2325///
2326static void ExpandAnonymousFieldDesignator(Sema &SemaRef,
2327 DesignatedInitExpr *DIE,
2328 unsigned DesigIdx,
2329 IndirectFieldDecl *IndirectField) {
2330 typedef DesignatedInitExpr::Designator Designator;
2331
2332 // Build the replacement designators.
2333 SmallVector<Designator, 4> Replacements;
2334 for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(),
2335 PE = IndirectField->chain_end(); PI != PE; ++PI) {
2336 if (PI + 1 == PE)
2337 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
2338 DIE->getDesignator(DesigIdx)->getDotLoc(),
2339 DIE->getDesignator(DesigIdx)->getFieldLoc()));
2340 else
2341 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
2342 SourceLocation(), SourceLocation()));
2343 assert(isa<FieldDecl>(*PI))(static_cast <bool> (isa<FieldDecl>(*PI)) ? void (
0) : __assert_fail ("isa<FieldDecl>(*PI)", "clang/lib/Sema/SemaInit.cpp"
, 2343, __extension__ __PRETTY_FUNCTION__))
;
2344 Replacements.back().setField(cast<FieldDecl>(*PI));
2345 }
2346
2347 // Expand the current designator into the set of replacement
2348 // designators, so we have a full subobject path down to where the
2349 // member of the anonymous struct/union is actually stored.
2350 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0],
2351 &Replacements[0] + Replacements.size());
2352}
2353
2354static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef,
2355 DesignatedInitExpr *DIE) {
2356 unsigned NumIndexExprs = DIE->getNumSubExprs() - 1;
2357 SmallVector<Expr*, 4> IndexExprs(NumIndexExprs);
2358 for (unsigned I = 0; I < NumIndexExprs; ++I)
2359 IndexExprs[I] = DIE->getSubExpr(I + 1);
2360 return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators(),
2361 IndexExprs,
2362 DIE->getEqualOrColonLoc(),
2363 DIE->usesGNUSyntax(), DIE->getInit());
2364}
2365
2366namespace {
2367
2368// Callback to only accept typo corrections that are for field members of
2369// the given struct or union.
2370class FieldInitializerValidatorCCC final : public CorrectionCandidateCallback {
2371 public:
2372 explicit FieldInitializerValidatorCCC(RecordDecl *RD)
2373 : Record(RD) {}
2374
2375 bool ValidateCandidate(const TypoCorrection &candidate) override {
2376 FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>();
2377 return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record);
2378 }
2379
2380 std::unique_ptr<CorrectionCandidateCallback> clone() override {
2381 return std::make_unique<FieldInitializerValidatorCCC>(*this);
2382 }
2383
2384 private:
2385 RecordDecl *Record;
2386};
2387
2388} // end anonymous namespace
2389
2390/// Check the well-formedness of a C99 designated initializer.
2391///
2392/// Determines whether the designated initializer @p DIE, which
2393/// resides at the given @p Index within the initializer list @p
2394/// IList, is well-formed for a current object of type @p DeclType
2395/// (C99 6.7.8). The actual subobject that this designator refers to
2396/// within the current subobject is returned in either
2397/// @p NextField or @p NextElementIndex (whichever is appropriate).
2398///
2399/// @param IList The initializer list in which this designated
2400/// initializer occurs.
2401///
2402/// @param DIE The designated initializer expression.
2403///
2404/// @param DesigIdx The index of the current designator.
2405///
2406/// @param CurrentObjectType The type of the "current object" (C99 6.7.8p17),
2407/// into which the designation in @p DIE should refer.
2408///
2409/// @param NextField If non-NULL and the first designator in @p DIE is
2410/// a field, this will be set to the field declaration corresponding
2411/// to the field named by the designator. On input, this is expected to be
2412/// the next field that would be initialized in the absence of designation,
2413/// if the complete object being initialized is a struct.
2414///
2415/// @param NextElementIndex If non-NULL and the first designator in @p
2416/// DIE is an array designator or GNU array-range designator, this
2417/// will be set to the last index initialized by this designator.
2418///
2419/// @param Index Index into @p IList where the designated initializer
2420/// @p DIE occurs.
2421///
2422/// @param StructuredList The initializer list expression that
2423/// describes all of the subobject initializers in the order they'll
2424/// actually be initialized.
2425///
2426/// @returns true if there was an error, false otherwise.
2427bool
2428InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity,
2429 InitListExpr *IList,
2430 DesignatedInitExpr *DIE,
2431 unsigned DesigIdx,
2432 QualType &CurrentObjectType,
2433 RecordDecl::field_iterator *NextField,
2434 llvm::APSInt *NextElementIndex,
2435 unsigned &Index,
2436 InitListExpr *StructuredList,
2437 unsigned &StructuredIndex,
2438 bool FinishSubobjectInit,
2439 bool TopLevelObject) {
2440 if (DesigIdx == DIE->size()) {
2441 // C++20 designated initialization can result in direct-list-initialization
2442 // of the designated subobject. This is the only way that we can end up
2443 // performing direct initialization as part of aggregate initialization, so
2444 // it needs special handling.
2445 if (DIE->isDirectInit()) {
2446 Expr *Init = DIE->getInit();
2447 assert(isa<InitListExpr>(Init) &&(static_cast <bool> (isa<InitListExpr>(Init) &&
"designator result in direct non-list initialization?") ? void
(0) : __assert_fail ("isa<InitListExpr>(Init) && \"designator result in direct non-list initialization?\""
, "clang/lib/Sema/SemaInit.cpp", 2448, __extension__ __PRETTY_FUNCTION__
))
2448 "designator result in direct non-list initialization?")(static_cast <bool> (isa<InitListExpr>(Init) &&
"designator result in direct non-list initialization?") ? void
(0) : __assert_fail ("isa<InitListExpr>(Init) && \"designator result in direct non-list initialization?\""
, "clang/lib/Sema/SemaInit.cpp", 2448, __extension__ __PRETTY_FUNCTION__
))
;
2449 InitializationKind Kind = InitializationKind::CreateDirectList(
2450 DIE->getBeginLoc(), Init->getBeginLoc(), Init->getEndLoc());
2451 InitializationSequence Seq(SemaRef, Entity, Kind, Init,
2452 /*TopLevelOfInitList*/ true);
2453 if (StructuredList) {
2454 ExprResult Result = VerifyOnly
2455 ? getDummyInit()
2456 : Seq.Perform(SemaRef, Entity, Kind, Init);
2457 UpdateStructuredListElement(StructuredList, StructuredIndex,
2458 Result.get());
2459 }
2460 ++Index;
2461 return !Seq;
2462 }
2463
2464 // Check the actual initialization for the designated object type.
2465 bool prevHadError = hadError;
2466
2467 // Temporarily remove the designator expression from the
2468 // initializer list that the child calls see, so that we don't try
2469 // to re-process the designator.
2470 unsigned OldIndex = Index;
2471 IList->setInit(OldIndex, DIE->getInit());
2472
2473 CheckSubElementType(Entity, IList, CurrentObjectType, Index, StructuredList,
2474 StructuredIndex, /*DirectlyDesignated=*/true);
2475
2476 // Restore the designated initializer expression in the syntactic
2477 // form of the initializer list.
2478 if (IList->getInit(OldIndex) != DIE->getInit())
2479 DIE->setInit(IList->getInit(OldIndex));
2480 IList->setInit(OldIndex, DIE);
2481
2482 return hadError && !prevHadError;
2483 }
2484
2485 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx);
2486 bool IsFirstDesignator = (DesigIdx == 0);
2487 if (IsFirstDesignator ? FullyStructuredList : StructuredList) {
2488 // Determine the structural initializer list that corresponds to the
2489 // current subobject.
2490 if (IsFirstDesignator)
2491 StructuredList = FullyStructuredList;
2492 else {
2493 Expr *ExistingInit = StructuredIndex < StructuredList->getNumInits() ?
2494 StructuredList->getInit(StructuredIndex) : nullptr;
2495 if (!ExistingInit && StructuredList->hasArrayFiller())
2496 ExistingInit = StructuredList->getArrayFiller();
2497
2498 if (!ExistingInit)
2499 StructuredList = getStructuredSubobjectInit(
2500 IList, Index, CurrentObjectType, StructuredList, StructuredIndex,
2501 SourceRange(D->getBeginLoc(), DIE->getEndLoc()));
2502 else if (InitListExpr *Result = dyn_cast<InitListExpr>(ExistingInit))
2503 StructuredList = Result;
2504 else {
2505 // We are creating an initializer list that initializes the
2506 // subobjects of the current object, but there was already an
2507 // initialization that completely initialized the current
2508 // subobject, e.g., by a compound literal:
2509 //
2510 // struct X { int a, b; };
2511 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
2512 //
2513 // Here, xs[0].a == 1 and xs[0].b == 3, since the second,
2514 // designated initializer re-initializes only its current object
2515 // subobject [0].b.
2516 diagnoseInitOverride(ExistingInit,
2517 SourceRange(D->getBeginLoc(), DIE->getEndLoc()),
2518 /*FullyOverwritten=*/false);
2519
2520 if (!VerifyOnly) {
2521 if (DesignatedInitUpdateExpr *E =
2522 dyn_cast<DesignatedInitUpdateExpr>(ExistingInit))
2523 StructuredList = E->getUpdater();
2524 else {
2525 DesignatedInitUpdateExpr *DIUE = new (SemaRef.Context)
2526 DesignatedInitUpdateExpr(SemaRef.Context, D->getBeginLoc(),
2527 ExistingInit, DIE->getEndLoc());
2528 StructuredList->updateInit(SemaRef.Context, StructuredIndex, DIUE);
2529 StructuredList = DIUE->getUpdater();
2530 }
2531 } else {
2532 // We don't need to track the structured representation of a
2533 // designated init update of an already-fully-initialized object in
2534 // verify-only mode. The only reason we would need the structure is
2535 // to determine where the uninitialized "holes" are, and in this
2536 // case, we know there aren't any and we can't introduce any.
2537 StructuredList = nullptr;
2538 }
2539 }
2540 }
2541 }
2542
2543 if (D->isFieldDesignator()) {
2544 // C99 6.7.8p7:
2545 //
2546 // If a designator has the form
2547 //
2548 // . identifier
2549 //
2550 // then the current object (defined below) shall have
2551 // structure or union type and the identifier shall be the
2552 // name of a member of that type.
2553 const RecordType *RT = CurrentObjectType->getAs<RecordType>();
2554 if (!RT) {
2555 SourceLocation Loc = D->getDotLoc();
2556 if (Loc.isInvalid())
2557 Loc = D->getFieldLoc();
2558 if (!VerifyOnly)
2559 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr)
2560 << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType;
2561 ++Index;
2562 return true;
2563 }
2564
2565 FieldDecl *KnownField = D->getField();
2566 if (!KnownField) {
2567 IdentifierInfo *FieldName = D->getFieldName();
2568 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName);
2569 for (NamedDecl *ND : Lookup) {
2570 if (auto *FD = dyn_cast<FieldDecl>(ND)) {
2571 KnownField = FD;
2572 break;
2573 }
2574 if (auto *IFD = dyn_cast<IndirectFieldDecl>(ND)) {
2575 // In verify mode, don't modify the original.
2576 if (VerifyOnly)
2577 DIE = CloneDesignatedInitExpr(SemaRef, DIE);
2578 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IFD);
2579 D = DIE->getDesignator(DesigIdx);
2580 KnownField = cast<FieldDecl>(*IFD->chain_begin());
2581 break;
2582 }
2583 }
2584 if (!KnownField) {
2585 if (VerifyOnly) {
2586 ++Index;
2587 return true; // No typo correction when just trying this out.
2588 }
2589
2590 // Name lookup found something, but it wasn't a field.
2591 if (!Lookup.empty()) {
2592 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield)
2593 << FieldName;
2594 SemaRef.Diag(Lookup.front()->getLocation(),
2595 diag::note_field_designator_found);
2596 ++Index;
2597 return true;
2598 }
2599
2600 // Name lookup didn't find anything.
2601 // Determine whether this was a typo for another field name.
2602 FieldInitializerValidatorCCC CCC(RT->getDecl());
2603 if (TypoCorrection Corrected = SemaRef.CorrectTypo(
2604 DeclarationNameInfo(FieldName, D->getFieldLoc()),
2605 Sema::LookupMemberName, /*Scope=*/nullptr, /*SS=*/nullptr, CCC,
2606 Sema::CTK_ErrorRecovery, RT->getDecl())) {
2607 SemaRef.diagnoseTypo(
2608 Corrected,
2609 SemaRef.PDiag(diag::err_field_designator_unknown_suggest)
2610 << FieldName << CurrentObjectType);
2611 KnownField = Corrected.getCorrectionDeclAs<FieldDecl>();
2612 hadError = true;
2613 } else {
2614 // Typo correction didn't find anything.
2615 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown)
2616 << FieldName << CurrentObjectType;
2617 ++Index;
2618 return true;
2619 }
2620 }
2621 }
2622
2623 unsigned NumBases = 0;
2624 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
2625 NumBases = CXXRD->getNumBases();
2626
2627 unsigned FieldIndex = NumBases;
2628
2629 for (auto *FI : RT->getDecl()->fields()) {
2630 if (FI->isUnnamedBitfield())
2631 continue;
2632 if (declaresSameEntity(KnownField, FI)) {
2633 KnownField = FI;
2634 break;
2635 }
2636 ++FieldIndex;
2637 }
2638
2639 RecordDecl::field_iterator Field =
2640 RecordDecl::field_iterator(DeclContext::decl_iterator(KnownField));
2641
2642 // All of the fields of a union are located at the same place in
2643 // the initializer list.
2644 if (RT->getDecl()->isUnion()) {
2645 FieldIndex = 0;
2646 if (StructuredList) {
2647 FieldDecl *CurrentField = StructuredList->getInitializedFieldInUnion();
2648 if (CurrentField && !declaresSameEntity(CurrentField, *Field)) {
2649 assert(StructuredList->getNumInits() == 1(static_cast <bool> (StructuredList->getNumInits() ==
1 && "A union should never have more than one initializer!"
) ? void (0) : __assert_fail ("StructuredList->getNumInits() == 1 && \"A union should never have more than one initializer!\""
, "clang/lib/Sema/SemaInit.cpp", 2650, __extension__ __PRETTY_FUNCTION__
))
2650 && "A union should never have more than one initializer!")(static_cast <bool> (StructuredList->getNumInits() ==
1 && "A union should never have more than one initializer!"
) ? void (0) : __assert_fail ("StructuredList->getNumInits() == 1 && \"A union should never have more than one initializer!\""
, "clang/lib/Sema/SemaInit.cpp", 2650, __extension__ __PRETTY_FUNCTION__
))
;
2651
2652 Expr *ExistingInit = StructuredList->getInit(0);
2653 if (ExistingInit) {
2654 // We're about to throw away an initializer, emit warning.
2655 diagnoseInitOverride(
2656 ExistingInit, SourceRange(D->getBeginLoc(), DIE->getEndLoc()));
2657 }
2658
2659 // remove existing initializer
2660 StructuredList->resizeInits(SemaRef.Context, 0);
2661 StructuredList->setInitializedFieldInUnion(nullptr);
2662 }
2663
2664 StructuredList->setInitializedFieldInUnion(*Field);
2665 }
2666 }
2667
2668 // Make sure we can use this declaration.
2669 bool InvalidUse;
2670 if (VerifyOnly)
2671 InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
2672 else
2673 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc());
2674 if (InvalidUse) {
2675 ++Index;
2676 return true;
2677 }
2678
2679 // C++20 [dcl.init.list]p3:
2680 // The ordered identifiers in the designators of the designated-
2681 // initializer-list shall form a subsequence of the ordered identifiers
2682 // in the direct non-static data members of T.
2683 //
2684 // Note that this is not a condition on forming the aggregate
2685 // initialization, only on actually performing initialization,
2686 // so it is not checked in VerifyOnly mode.
2687 //
2688 // FIXME: This is the only reordering diagnostic we produce, and it only
2689 // catches cases where we have a top-level field designator that jumps
2690 // backwards. This is the only such case that is reachable in an
2691 // otherwise-valid C++20 program, so is the only case that's required for
2692 // conformance, but for consistency, we should diagnose all the other
2693 // cases where a designator takes us backwards too.
2694 if (IsFirstDesignator && !VerifyOnly && SemaRef.getLangOpts().CPlusPlus &&
2695 NextField &&
2696 (*NextField == RT->getDecl()->field_end() ||
2697 (*NextField)->getFieldIndex() > Field->getFieldIndex() + 1)) {
2698 // Find the field that we just initialized.
2699 FieldDecl *PrevField = nullptr;
2700 for (auto FI = RT->getDecl()->field_begin();
2701 FI != RT->getDecl()->field_end(); ++FI) {
2702 if (FI->isUnnamedBitfield())
2703 continue;
2704 if (*NextField != RT->getDecl()->field_end() &&
2705 declaresSameEntity(*FI, **NextField))
2706 break;
2707 PrevField = *FI;
2708 }
2709
2710 if (PrevField &&
2711 PrevField->getFieldIndex() > KnownField->getFieldIndex()) {
2712 SemaRef.Diag(DIE->getBeginLoc(), diag::ext_designated_init_reordered)
2713 << KnownField << PrevField << DIE->getSourceRange();
2714
2715 unsigned OldIndex = NumBases + PrevField->getFieldIndex();
2716 if (StructuredList && OldIndex <= StructuredList->getNumInits()) {
2717 if (Expr *PrevInit = StructuredList->getInit(OldIndex)) {
2718 SemaRef.Diag(PrevInit->getBeginLoc(),
2719 diag::note_previous_field_init)
2720 << PrevField << PrevInit->getSourceRange();
2721 }
2722 }
2723 }
2724 }
2725
2726
2727 // Update the designator with the field declaration.
2728 if (!VerifyOnly)
2729 D->setField(*Field);
2730
2731 // Make sure that our non-designated initializer list has space
2732 // for a subobject corresponding to this field.
2733 if (StructuredList && FieldIndex >= StructuredList->getNumInits())
2734 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1);
2735
2736 // This designator names a flexible array member.
2737 if (Field->getType()->isIncompleteArrayType()) {
2738 bool Invalid = false;
2739 if ((DesigIdx + 1) != DIE->size()) {
2740 // We can't designate an object within the flexible array
2741 // member (because GCC doesn't allow it).
2742 if (!VerifyOnly) {
2743 DesignatedInitExpr::Designator *NextD
2744 = DIE->getDesignator(DesigIdx + 1);
2745 SemaRef.Diag(NextD->getBeginLoc(),
2746 diag::err_designator_into_flexible_array_member)
2747 << SourceRange(NextD->getBeginLoc(), DIE->getEndLoc());
2748 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2749 << *Field;
2750 }
2751 Invalid = true;
2752 }
2753
2754 if (!hadError && !isa<InitListExpr>(DIE->getInit()) &&
2755 !isa<StringLiteral>(DIE->getInit())) {
2756 // The initializer is not an initializer list.
2757 if (!VerifyOnly) {
2758 SemaRef.Diag(DIE->getInit()->getBeginLoc(),
2759 diag::err_flexible_array_init_needs_braces)
2760 << DIE->getInit()->getSourceRange();
2761 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2762 << *Field;
2763 }
2764 Invalid = true;
2765 }
2766
2767 // Check GNU flexible array initializer.
2768 if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field,
2769 TopLevelObject))
2770 Invalid = true;
2771
2772 if (Invalid) {
2773 ++Index;
2774 return true;
2775 }
2776
2777 // Initialize the array.
2778 bool prevHadError = hadError;
2779 unsigned newStructuredIndex = FieldIndex;
2780 unsigned OldIndex = Index;
2781 IList->setInit(Index, DIE->getInit());
2782
2783 InitializedEntity MemberEntity =
2784 InitializedEntity::InitializeMember(*Field, &Entity);
2785 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2786 StructuredList, newStructuredIndex);
2787
2788 IList->setInit(OldIndex, DIE);
2789 if (hadError && !prevHadError) {
2790 ++Field;
2791 ++FieldIndex;
2792 if (NextField)
2793 *NextField = Field;
2794 StructuredIndex = FieldIndex;
2795 return true;
2796 }
2797 } else {
2798 // Recurse to check later designated subobjects.
2799 QualType FieldType = Field->getType();
2800 unsigned newStructuredIndex = FieldIndex;
2801
2802 InitializedEntity MemberEntity =
2803 InitializedEntity::InitializeMember(*Field, &Entity);
2804 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1,
2805 FieldType, nullptr, nullptr, Index,
2806 StructuredList, newStructuredIndex,
2807 FinishSubobjectInit, false))
2808 return true;
2809 }
2810
2811 // Find the position of the next field to be initialized in this
2812 // subobject.
2813 ++Field;
2814 ++FieldIndex;
2815
2816 // If this the first designator, our caller will continue checking
2817 // the rest of this struct/class/union subobject.
2818 if (IsFirstDesignator) {
2819 if (NextField)
2820 *NextField = Field;
2821 StructuredIndex = FieldIndex;
2822 return false;
2823 }
2824
2825 if (!FinishSubobjectInit)
2826 return false;
2827
2828 // We've already initialized something in the union; we're done.
2829 if (RT->getDecl()->isUnion())
2830 return hadError;
2831
2832 // Check the remaining fields within this class/struct/union subobject.
2833 bool prevHadError = hadError;
2834
2835 auto NoBases =
2836 CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
2837 CXXRecordDecl::base_class_iterator());
2838 CheckStructUnionTypes(Entity, IList, CurrentObjectType, NoBases, Field,
2839 false, Index, StructuredList, FieldIndex);
2840 return hadError && !prevHadError;
2841 }
2842
2843 // C99 6.7.8p6:
2844 //
2845 // If a designator has the form
2846 //
2847 // [ constant-expression ]
2848 //
2849 // then the current object (defined below) shall have array
2850 // type and the expression shall be an integer constant
2851 // expression. If the array is of unknown size, any
2852 // nonnegative value is valid.
2853 //
2854 // Additionally, cope with the GNU extension that permits
2855 // designators of the form
2856 //
2857 // [ constant-expression ... constant-expression ]
2858 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType);
2859 if (!AT) {
2860 if (!VerifyOnly)
2861 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array)
2862 << CurrentObjectType;
2863 ++Index;
2864 return true;
2865 }
2866
2867 Expr *IndexExpr = nullptr;
2868 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex;
2869 if (D->isArrayDesignator()) {
2870 IndexExpr = DIE->getArrayIndex(*D);
2871 DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context);
2872 DesignatedEndIndex = DesignatedStartIndex;
2873 } else {
2874 assert(D->isArrayRangeDesignator() && "Need array-range designator")(static_cast <bool> (D->isArrayRangeDesignator() &&
"Need array-range designator") ? void (0) : __assert_fail ("D->isArrayRangeDesignator() && \"Need array-range designator\""
, "clang/lib/Sema/SemaInit.cpp", 2874, __extension__ __PRETTY_FUNCTION__
))
;
2875
2876 DesignatedStartIndex =
2877 DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context);
2878 DesignatedEndIndex =
2879 DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context);
2880 IndexExpr = DIE->getArrayRangeEnd(*D);
2881
2882 // Codegen can't handle evaluating array range designators that have side
2883 // effects, because we replicate the AST value for each initialized element.
2884 // As such, set the sawArrayRangeDesignator() bit if we initialize multiple
2885 // elements with something that has a side effect, so codegen can emit an
2886 // "error unsupported" error instead of miscompiling the app.
2887 if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&&
2888 DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly)
2889 FullyStructuredList->sawArrayRangeDesignator();
2890 }
2891
2892 if (isa<ConstantArrayType>(AT)) {
2893 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false);
2894 DesignatedStartIndex
2895 = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth());
2896 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned());
2897 DesignatedEndIndex
2898 = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth());
2899 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned());
2900 if (DesignatedEndIndex >= MaxElements) {
2901 if (!VerifyOnly)
2902 SemaRef.Diag(IndexExpr->getBeginLoc(),
2903 diag::err_array_designator_too_large)
2904 << toString(DesignatedEndIndex, 10) << toString(MaxElements, 10)
2905 << IndexExpr->getSourceRange();
2906 ++Index;
2907 return true;
2908 }
2909 } else {
2910 unsigned DesignatedIndexBitWidth =
2911 ConstantArrayType::getMaxSizeBits(SemaRef.Context);
2912 DesignatedStartIndex =
2913 DesignatedStartIndex.extOrTrunc(DesignatedIndexBitWidth);
2914 DesignatedEndIndex =
2915 DesignatedEndIndex.extOrTrunc(DesignatedIndexBitWidth);
2916 DesignatedStartIndex.setIsUnsigned(true);
2917 DesignatedEndIndex.setIsUnsigned(true);
2918 }
2919
2920 bool IsStringLiteralInitUpdate =
2921 StructuredList && StructuredList->isStringLiteralInit();
2922 if (IsStringLiteralInitUpdate && VerifyOnly) {
2923 // We're just verifying an update to a string literal init. We don't need
2924 // to split the string up into individual characters to do that.
2925 StructuredList = nullptr;
2926 } else if (IsStringLiteralInitUpdate) {
2927 // We're modifying a string literal init; we have to decompose the string
2928 // so we can modify the individual characters.
2929 ASTContext &Context = SemaRef.Context;
2930 Expr *SubExpr = StructuredList->getInit(0)->IgnoreParenImpCasts();
2931
2932 // Compute the character type
2933 QualType CharTy = AT->getElementType();
2934
2935 // Compute the type of the integer literals.
2936 QualType PromotedCharTy = CharTy;
2937 if (CharTy->isPromotableIntegerType())
2938 PromotedCharTy = Context.getPromotedIntegerType(CharTy);
2939 unsigned PromotedCharTyWidth = Context.getTypeSize(PromotedCharTy);
2940
2941 if (StringLiteral *SL = dyn_cast<StringLiteral>(SubExpr)) {
2942 // Get the length of the string.
2943 uint64_t StrLen = SL->getLength();
2944 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2945 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2946 StructuredList->resizeInits(Context, StrLen);
2947
2948 // Build a literal for each character in the string, and put them into
2949 // the init list.
2950 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2951 llvm::APInt CodeUnit(PromotedCharTyWidth, SL->getCodeUnit(i));
2952 Expr *Init = new (Context) IntegerLiteral(
2953 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2954 if (CharTy != PromotedCharTy)
2955 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
2956 Init, nullptr, VK_PRValue,
2957 FPOptionsOverride());
2958 StructuredList->updateInit(Context, i, Init);
2959 }
2960 } else {
2961 ObjCEncodeExpr *E = cast<ObjCEncodeExpr>(SubExpr);
2962 std::string Str;
2963 Context.getObjCEncodingForType(E->getEncodedType(), Str);
2964
2965 // Get the length of the string.
2966 uint64_t StrLen = Str.size();
2967 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2968 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2969 StructuredList->resizeInits(Context, StrLen);
2970
2971 // Build a literal for each character in the string, and put them into
2972 // the init list.
2973 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2974 llvm::APInt CodeUnit(PromotedCharTyWidth, Str[i]);
2975 Expr *Init = new (Context) IntegerLiteral(
2976 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2977 if (CharTy != PromotedCharTy)
2978 Init = ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast,
2979 Init, nullptr, VK_PRValue,
2980 FPOptionsOverride());
2981 StructuredList->updateInit(Context, i, Init);
2982 }
2983 }
2984 }
2985
2986 // Make sure that our non-designated initializer list has space
2987 // for a subobject corresponding to this array element.
2988 if (StructuredList &&
2989 DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits())
2990 StructuredList->resizeInits(SemaRef.Context,
2991 DesignatedEndIndex.getZExtValue() + 1);
2992
2993 // Repeatedly perform subobject initializations in the range
2994 // [DesignatedStartIndex, DesignatedEndIndex].
2995
2996 // Move to the next designator
2997 unsigned ElementIndex = DesignatedStartIndex.getZExtValue();
2998 unsigned OldIndex = Index;
2999
3000 InitializedEntity ElementEntity =
3001 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
3002
3003 while (DesignatedStartIndex <= DesignatedEndIndex) {
3004 // Recurse to check later designated subobjects.
3005 QualType ElementType = AT->getElementType();
3006 Index = OldIndex;
3007
3008 ElementEntity.setElementIndex(ElementIndex);
3009 if (CheckDesignatedInitializer(
3010 ElementEntity, IList, DIE, DesigIdx + 1, ElementType, nullptr,
3011 nullptr, Index, StructuredList, ElementIndex,
3012 FinishSubobjectInit && (DesignatedStartIndex == DesignatedEndIndex),
3013 false))
3014 return true;
3015
3016 // Move to the next index in the array that we'll be initializing.
3017 ++DesignatedStartIndex;
3018 ElementIndex = DesignatedStartIndex.getZExtValue();
3019 }
3020
3021 // If this the first designator, our caller will continue checking
3022 // the rest of this array subobject.
3023 if (IsFirstDesignator) {
3024 if (NextElementIndex)
3025 *NextElementIndex = DesignatedStartIndex;
3026 StructuredIndex = ElementIndex;
3027 return false;
3028 }
3029
3030 if (!FinishSubobjectInit)
3031 return false;
3032
3033 // Check the remaining elements within this array subobject.
3034 bool prevHadError = hadError;
3035 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex,
3036 /*SubobjectIsDesignatorContext=*/false, Index,
3037 StructuredList, ElementIndex);
3038 return hadError && !prevHadError;
3039}
3040
3041// Get the structured initializer list for a subobject of type
3042// @p CurrentObjectType.
3043InitListExpr *
3044InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
3045 QualType CurrentObjectType,
3046 InitListExpr *StructuredList,
3047 unsigned StructuredIndex,
3048 SourceRange InitRange,
3049 bool IsFullyOverwritten) {
3050 if (!StructuredList)
3051 return nullptr;
3052
3053 Expr *ExistingInit = nullptr;
3054 if (StructuredIndex < StructuredList->getNumInits())
3055 ExistingInit = StructuredList->getInit(StructuredIndex);
3056
3057 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit))
3058 // There might have already been initializers for subobjects of the current
3059 // object, but a subsequent initializer list will overwrite the entirety
3060 // of the current object. (See DR 253 and C99 6.7.8p21). e.g.,
3061 //
3062 // struct P { char x[6]; };
3063 // struct P l = { .x[2] = 'x', .x = { [0] = 'f' } };
3064 //
3065 // The first designated initializer is ignored, and l.x is just "f".
3066 if (!IsFullyOverwritten)
3067 return Result;
3068
3069 if (ExistingInit) {
3070 // We are creating an initializer list that initializes the
3071 // subobjects of the current object, but there was already an
3072 // initialization that completely initialized the current
3073 // subobject:
3074 //
3075 // struct X { int a, b; };
3076 // struct X xs[] = { [0] = { 1, 2 }, [0].b = 3 };
3077 //
3078 // Here, xs[0].a == 1 and xs[0].b == 3, since the second,
3079 // designated initializer overwrites the [0].b initializer
3080 // from the prior initialization.
3081 //
3082 // When the existing initializer is an expression rather than an
3083 // initializer list, we cannot decompose and update it in this way.
3084 // For example:
3085 //
3086 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
3087 //
3088 // This case is handled by CheckDesignatedInitializer.
3089 diagnoseInitOverride(ExistingInit, InitRange);
3090 }
3091
3092 unsigned ExpectedNumInits = 0;
3093 if (Index < IList->getNumInits()) {
3094 if (auto *Init = dyn_cast_or_null<InitListExpr>(IList->getInit(Index)))
3095 ExpectedNumInits = Init->getNumInits();
3096 else
3097 ExpectedNumInits = IList->getNumInits() - Index;
3098 }
3099
3100 InitListExpr *Result =
3101 createInitListExpr(CurrentObjectType, InitRange, ExpectedNumInits);
3102
3103 // Link this new initializer list into the structured initializer
3104 // lists.
3105 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result);
3106 return Result;
3107}
3108
3109InitListExpr *
3110InitListChecker::createInitListExpr(QualType CurrentObjectType,
3111 SourceRange InitRange,
3112 unsigned ExpectedNumInits) {
3113 InitListExpr *Result
3114 = new (SemaRef.Context) InitListExpr(SemaRef.Context,
3115 InitRange.getBegin(), None,
3116 InitRange.getEnd());
3117
3118 QualType ResultType = CurrentObjectType;
3119 if (!ResultType->isArrayType())
3120 ResultType = ResultType.getNonLValueExprType(SemaRef.Context);
3121 Result->setType(ResultType);
3122
3123 // Pre-allocate storage for the structured initializer list.
3124 unsigned NumElements = 0;
3125
3126 if (const ArrayType *AType
3127 = SemaRef.Context.getAsArrayType(CurrentObjectType)) {
3128 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) {
3129 NumElements = CAType->getSize().getZExtValue();
3130 // Simple heuristic so that we don't allocate a very large
3131 // initializer with many empty entries at the end.
3132 if (NumElements > ExpectedNumInits)
3133 NumElements = 0;
3134 }
3135 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>()) {
3136 NumElements = VType->getNumElements();
3137 } else if (CurrentObjectType->isRecordType()) {
3138 NumElements = numStructUnionElements(CurrentObjectType);
3139 }
3140
3141 Result->reserveInits(SemaRef.Context, NumElements);
3142
3143 return Result;
3144}
3145
3146/// Update the initializer at index @p StructuredIndex within the
3147/// structured initializer list to the value @p expr.
3148void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList,
3149 unsigned &StructuredIndex,
3150 Expr *expr) {
3151 // No structured initializer list to update
3152 if (!StructuredList)
3153 return;
3154
3155 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context,
3156 StructuredIndex, expr)) {
3157 // This initializer overwrites a previous initializer.
3158 // No need to diagnose when `expr` is nullptr because a more relevant
3159 // diagnostic has already been issued and this diagnostic is potentially
3160 // noise.
3161 if (expr)
3162 diagnoseInitOverride(PrevInit, expr->getSourceRange());
3163 }
3164
3165 ++StructuredIndex;
3166}
3167
3168/// Determine whether we can perform aggregate initialization for the purposes
3169/// of overload resolution.
3170bool Sema::CanPerformAggregateInitializationForOverloadResolution(
3171 const InitializedEntity &Entity, InitListExpr *From) {
3172 QualType Type = Entity.getType();
3173 InitListChecker Check(*this, Entity, From, Type, /*VerifyOnly=*/true,
3174 /*TreatUnavailableAsInvalid=*/false,
3175 /*InOverloadResolution=*/true);
3176 return !Check.HadError();
3177}
3178
3179/// Check that the given Index expression is a valid array designator
3180/// value. This is essentially just a wrapper around
3181/// VerifyIntegerConstantExpression that also checks for negative values
3182/// and produces a reasonable diagnostic if there is a
3183/// failure. Returns the index expression, possibly with an implicit cast
3184/// added, on success. If everything went okay, Value will receive the
3185/// value of the constant expression.
3186static ExprResult
3187CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) {
3188 SourceLocation Loc = Index->getBeginLoc();
3189
3190 // Make sure this is an integer constant expression.
3191 ExprResult Result =
3192 S.VerifyIntegerConstantExpression(Index, &Value, Sema::AllowFold);
3193 if (Result.isInvalid())
3194 return Result;
3195
3196 if (Value.isSigned() && Value.isNegative())
3197 return S.Diag(Loc, diag::err_array_designator_negative)
3198 << toString(Value, 10) << Index->getSourceRange();
3199
3200 Value.setIsUnsigned(true);
3201 return Result;
3202}
3203
3204ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig,
3205 SourceLocation EqualOrColonLoc,
3206 bool GNUSyntax,
3207 ExprResult Init) {
3208 typedef DesignatedInitExpr::Designator ASTDesignator;
3209
3210 bool Invalid = false;
3211 SmallVector<ASTDesignator, 32> Designators;
3212 SmallVector<Expr *, 32> InitExpressions;
3213
3214 // Build designators and check array designator expressions.
3215 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) {
3216 const Designator &D = Desig.getDesignator(Idx);
3217 switch (D.getKind()) {
3218 case Designator::FieldDesignator:
3219 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(),
3220 D.getFieldLoc()));
3221 break;
3222
3223 case Designator::ArrayDesignator: {
3224 Expr *Index = static_cast<Expr *>(D.getArrayIndex());
3225 llvm::APSInt IndexValue;
3226 if (!Index->isTypeDependent() && !Index->isValueDependent())
3227 Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).get();
3228 if (!Index)
3229 Invalid = true;
3230 else {
3231 Designators.push_back(ASTDesignator(InitExpressions.size(),
3232 D.getLBracketLoc(),
3233 D.getRBracketLoc()));
3234 InitExpressions.push_back(Index);
3235 }
3236 break;
3237 }
3238
3239 case Designator::ArrayRangeDesignator: {
3240 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart());
3241 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd());
3242 llvm::APSInt StartValue;
3243 llvm::APSInt EndValue;
3244 bool StartDependent = StartIndex->isTypeDependent() ||
3245 StartIndex->isValueDependent();
3246 bool EndDependent = EndIndex->isTypeDependent() ||
3247 EndIndex->isValueDependent();
3248 if (!StartDependent)
3249 StartIndex =
3250 CheckArrayDesignatorExpr(*this, StartIndex, StartValue).get();
3251 if (!EndDependent)
3252 EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).get();
3253
3254 if (!StartIndex || !EndIndex)
3255 Invalid = true;
3256 else {
3257 // Make sure we're comparing values with the same bit width.
3258 if (StartDependent || EndDependent) {
3259 // Nothing to compute.
3260 } else if (StartValue.getBitWidth() > EndValue.getBitWidth())
3261 EndValue = EndValue.extend(StartValue.getBitWidth());
3262 else if (StartValue.getBitWidth() < EndValue.getBitWidth())
3263 StartValue = StartValue.extend(EndValue.getBitWidth());
3264
3265 if (!StartDependent && !EndDependent && EndValue < StartValue) {
3266 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range)
3267 << toString(StartValue, 10) << toString(EndValue, 10)
3268 << StartIndex->getSourceRange() << EndIndex->getSourceRange();
3269 Invalid = true;
3270 } else {
3271 Designators.push_back(ASTDesignator(InitExpressions.size(),
3272 D.getLBracketLoc(),
3273 D.getEllipsisLoc(),
3274 D.getRBracketLoc()));
3275 InitExpressions.push_back(StartIndex);
3276 InitExpressions.push_back(EndIndex);
3277 }
3278 }
3279 break;
3280 }
3281 }
3282 }
3283
3284 if (Invalid || Init.isInvalid())
3285 return ExprError();
3286
3287 // Clear out the expressions within the designation.
3288 Desig.ClearExprs(*this);
3289
3290 return DesignatedInitExpr::Create(Context, Designators, InitExpressions,
3291 EqualOrColonLoc, GNUSyntax,
3292 Init.getAs<Expr>());
3293}
3294
3295//===----------------------------------------------------------------------===//
3296// Initialization entity
3297//===----------------------------------------------------------------------===//
3298
3299InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index,
3300 const InitializedEntity &Parent)
3301 : Parent(&Parent), Index(Index)
3302{
3303 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) {
3304 Kind = EK_ArrayElement;
3305 Type = AT->getElementType();
3306 } else if (const VectorType *VT = Parent.getType()->getAs<VectorType>()) {
3307 Kind = EK_VectorElement;
3308 Type = VT->getElementType();
3309 } else {
3310 const ComplexType *CT = Parent.getType()->getAs<ComplexType>();
3311 assert(CT && "Unexpected type")(static_cast <bool> (CT && "Unexpected type") ?
void (0) : __assert_fail ("CT && \"Unexpected type\""
, "clang/lib/Sema/SemaInit.cpp", 3311, __extension__ __PRETTY_FUNCTION__
))
;
3312 Kind = EK_ComplexElement;
3313 Type = CT->getElementType();
3314 }
3315}
3316
3317InitializedEntity
3318InitializedEntity::InitializeBase(ASTContext &Context,
3319 const CXXBaseSpecifier *Base,
3320 bool IsInheritedVirtualBase,
3321 const InitializedEntity *Parent) {
3322 InitializedEntity Result;
3323 Result.Kind = EK_Base;
3324 Result.Parent = Parent;
3325 Result.Base = {Base, IsInheritedVirtualBase};
3326 Result.Type = Base->getType();
3327 return Result;
3328}
3329
3330DeclarationName InitializedEntity::getName() const {
3331 switch (getKind()) {
3332 case EK_Parameter:
3333 case EK_Parameter_CF_Audited: {
3334 ParmVarDecl *D = Parameter.getPointer();
3335 return (D ? D->getDeclName() : DeclarationName());
3336 }
3337
3338 case EK_Variable:
3339 case EK_Member:
3340 case EK_Binding:
3341 case EK_TemplateParameter:
3342 return Variable.VariableOrMember->getDeclName();
3343
3344 case EK_LambdaCapture:
3345 return DeclarationName(Capture.VarID);
3346
3347 case EK_Result:
3348 case EK_StmtExprResult:
3349 case EK_Exception:
3350 case EK_New:
3351 case EK_Temporary:
3352 case EK_Base:
3353 case EK_Delegating:
3354 case EK_ArrayElement:
3355 case EK_VectorElement:
3356 case EK_ComplexElement:
3357 case EK_BlockElement:
3358 case EK_LambdaToBlockConversionBlockElement:
3359 case EK_CompoundLiteralInit:
3360 case EK_RelatedResult:
3361 return DeclarationName();
3362 }
3363
3364 llvm_unreachable("Invalid EntityKind!")::llvm::llvm_unreachable_internal("Invalid EntityKind!", "clang/lib/Sema/SemaInit.cpp"
, 3364)
;
3365}
3366
3367ValueDecl *InitializedEntity::getDecl() const {
3368 switch (getKind()) {
3369 case EK_Variable:
3370 case EK_Member:
3371 case EK_Binding:
3372 case EK_TemplateParameter:
3373 return Variable.VariableOrMember;
3374
3375 case EK_Parameter:
3376 case EK_Parameter_CF_Audited:
3377 return Parameter.getPointer();
3378
3379 case EK_Result:
3380 case EK_StmtExprResult:
3381 case EK_Exception:
3382 case EK_New:
3383 case EK_Temporary:
3384 case EK_Base:
3385 case EK_Delegating:
3386 case EK_ArrayElement:
3387 case EK_VectorElement:
3388 case EK_ComplexElement:
3389 case EK_BlockElement:
3390 case EK_LambdaToBlockConversionBlockElement:
3391 case EK_LambdaCapture:
3392 case EK_CompoundLiteralInit:
3393 case EK_RelatedResult:
3394 return nullptr;
3395 }
3396
3397 llvm_unreachable("Invalid EntityKind!")::llvm::llvm_unreachable_internal("Invalid EntityKind!", "clang/lib/Sema/SemaInit.cpp"
, 3397)
;
3398}
3399
3400bool InitializedEntity::allowsNRVO() const {
3401 switch (getKind()) {
3402 case EK_Result:
3403 case EK_Exception:
3404 return LocAndNRVO.NRVO;
3405
3406 case EK_StmtExprResult:
3407 case EK_Variable:
3408 case EK_Parameter:
3409 case EK_Parameter_CF_Audited:
3410 case EK_TemplateParameter:
3411 case EK_Member:
3412 case EK_Binding:
3413 case EK_New:
3414 case EK_Temporary:
3415 case EK_CompoundLiteralInit:
3416 case EK_Base:
3417 case EK_Delegating:
3418 case EK_ArrayElement:
3419 case EK_VectorElement:
3420 case EK_ComplexElement:
3421 case EK_BlockElement:
3422 case EK_LambdaToBlockConversionBlockElement:
3423 case EK_LambdaCapture:
3424 case EK_RelatedResult:
3425 break;
3426 }
3427
3428 return false;
3429}
3430
3431unsigned InitializedEntity::dumpImpl(raw_ostream &OS) const {
3432 assert(getParent() != this)(static_cast <bool> (getParent() != this) ? void (0) : __assert_fail
("getParent() != this", "clang/lib/Sema/SemaInit.cpp", 3432,
__extension__ __PRETTY_FUNCTION__))
;
3433 unsigned Depth = getParent() ? getParent()->dumpImpl(OS) : 0;
3434 for (unsigned I = 0; I != Depth; ++I)
3435 OS << "`-";
3436
3437 switch (getKind()) {
3438 case EK_Variable: OS << "Variable"; break;
3439 case EK_Parameter: OS << "Parameter"; break;
3440 case EK_Parameter_CF_Audited: OS << "CF audited function Parameter";
3441 break;
3442 case EK_TemplateParameter: OS << "TemplateParameter"; break;
3443 case EK_Result: OS << "Result"; break;
3444 case EK_StmtExprResult: OS << "StmtExprResult"; break;
3445 case EK_Exception: OS << "Exception"; break;
3446 case EK_Member: OS << "Member"; break;
3447 case EK_Binding: OS << "Binding"; break;
3448 case EK_New: OS << "New"; break;
3449 case EK_Temporary: OS << "Temporary"; break;
3450 case EK_CompoundLiteralInit: OS << "CompoundLiteral";break;
3451 case EK_RelatedResult: OS << "RelatedResult"; break;
3452 case EK_Base: OS << "Base"; break;
3453 case EK_Delegating: OS << "Delegating"; break;
3454 case EK_ArrayElement: OS << "ArrayElement " << Index; break;
3455 case EK_VectorElement: OS << "VectorElement " << Index; break;
3456 case EK_ComplexElement: OS << "ComplexElement " << Index; break;
3457 case EK_BlockElement: OS << "Block"; break;
3458 case EK_LambdaToBlockConversionBlockElement:
3459 OS << "Block (lambda)";
3460 break;
3461 case EK_LambdaCapture:
3462 OS << "LambdaCapture ";
3463 OS << DeclarationName(Capture.VarID);
3464 break;
3465 }
3466
3467 if (auto *D = getDecl()) {
3468 OS << " ";
3469 D->printQualifiedName(OS);
3470 }
3471
3472 OS << " '" << getType() << "'\n";
3473
3474 return Depth + 1;
3475}
3476
3477LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void InitializedEntity::dump() const {
3478 dumpImpl(llvm::errs());
3479}
3480
3481//===----------------------------------------------------------------------===//
3482// Initialization sequence
3483//===----------------------------------------------------------------------===//
3484
3485void InitializationSequence::Step::Destroy() {
3486 switch (Kind) {
3487 case SK_ResolveAddressOfOverloadedFunction:
3488 case SK_CastDerivedToBasePRValue:
3489 case SK_CastDerivedToBaseXValue:
3490 case SK_CastDerivedToBaseLValue:
3491 case SK_BindReference:
3492 case SK_BindReferenceToTemporary:
3493 case SK_FinalCopy:
3494 case SK_ExtraneousCopyToTemporary:
3495 case SK_UserConversion:
3496 case SK_QualificationConversionPRValue:
3497 case SK_QualificationConversionXValue:
3498 case SK_QualificationConversionLValue:
3499 case SK_FunctionReferenceConversion:
3500 case SK_AtomicConversion:
3501 case SK_ListInitialization:
3502 case SK_UnwrapInitList:
3503 case SK_RewrapInitList:
3504 case SK_ConstructorInitialization:
3505 case SK_ConstructorInitializationFromList:
3506 case SK_ZeroInitialization:
3507 case SK_CAssignment:
3508 case SK_StringInit:
3509 case SK_ObjCObjectConversion:
3510 case SK_ArrayLoopIndex:
3511 case SK_ArrayLoopInit:
3512 case SK_ArrayInit:
3513 case SK_GNUArrayInit:
3514 case SK_ParenthesizedArrayInit:
3515 case SK_PassByIndirectCopyRestore:
3516 case SK_PassByIndirectRestore:
3517 case SK_ProduceObjCObject:
3518 case SK_StdInitializerList:
3519 case SK_StdInitializerListConstructorCall:
3520 case SK_OCLSamplerInit:
3521 case SK_OCLZeroOpaqueType:
3522 break;
3523
3524 case SK_ConversionSequence:
3525 case SK_ConversionSequenceNoNarrowing:
3526 delete ICS;
3527 }
3528}
3529
3530bool InitializationSequence::isDirectReferenceBinding() const {
3531 // There can be some lvalue adjustments after the SK_BindReference step.
3532 for (const Step &S : llvm::reverse(Steps)) {
3533 if (S.Kind == SK_BindReference)
3534 return true;
3535 if (S.Kind == SK_BindReferenceToTemporary)
3536 return false;
3537 }
3538 return false;
3539}
3540
3541bool InitializationSequence::isAmbiguous() const {
3542 if (!Failed())
3543 return false;
3544
3545 switch (getFailureKind()) {
3546 case FK_TooManyInitsForReference:
3547 case FK_ParenthesizedListInitForReference:
3548 case FK_ArrayNeedsInitList:
3549 case FK_ArrayNeedsInitListOrStringLiteral:
3550 case FK_ArrayNeedsInitListOrWideStringLiteral:
3551 case FK_NarrowStringIntoWideCharArray:
3552 case FK_WideStringIntoCharArray:
3553 case FK_IncompatWideStringIntoWideChar:
3554 case FK_PlainStringIntoUTF8Char:
3555 case FK_UTF8StringIntoPlainChar:
3556 case FK_AddressOfOverloadFailed: // FIXME: Could do better
3557 case FK_NonConstLValueReferenceBindingToTemporary:
3558 case FK_NonConstLValueReferenceBindingToBitfield:
3559 case FK_NonConstLValueReferenceBindingToVectorElement:
3560 case FK_NonConstLValueReferenceBindingToMatrixElement:
3561 case FK_NonConstLValueReferenceBindingToUnrelated:
3562 case FK_RValueReferenceBindingToLValue:
3563 case FK_ReferenceAddrspaceMismatchTemporary:
3564 case FK_ReferenceInitDropsQualifiers:
3565 case FK_ReferenceInitFailed:
3566 case FK_ConversionFailed:
3567 case FK_ConversionFromPropertyFailed:
3568 case FK_TooManyInitsForScalar:
3569 case FK_ParenthesizedListInitForScalar:
3570 case FK_ReferenceBindingToInitList:
3571 case FK_InitListBadDestinationType:
3572 case FK_DefaultInitOfConst:
3573 case FK_Incomplete:
3574 case FK_ArrayTypeMismatch:
3575 case FK_NonConstantArrayInit:
3576 case FK_ListInitializationFailed:
3577 case FK_VariableLengthArrayHasInitializer:
3578 case FK_PlaceholderType:
3579 case FK_ExplicitConstructor:
3580 case FK_AddressOfUnaddressableFunction:
3581 return false;
3582
3583 case FK_ReferenceInitOverloadFailed:
3584 case FK_UserConversionOverloadFailed:
3585 case FK_ConstructorOverloadFailed:
3586 case FK_ListConstructorOverloadFailed:
3587 return FailedOverloadResult == OR_Ambiguous;
3588 }
3589
3590 llvm_unreachable("Invalid EntityKind!")::llvm::llvm_unreachable_internal("Invalid EntityKind!", "clang/lib/Sema/SemaInit.cpp"
, 3590)
;
3591}
3592
3593bool InitializationSequence::isConstructorInitialization() const {
3594 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization;
3595}
3596
3597void
3598InitializationSequence
3599::AddAddressOverloadResolutionStep(FunctionDecl *Function,
3600 DeclAccessPair Found,
3601 bool HadMultipleCandidates) {
3602 Step S;
3603 S.Kind = SK_ResolveAddressOfOverloadedFunction;
3604 S.Type = Function->getType();
3605 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3606 S.Function.Function = Function;
3607 S.Function.FoundDecl = Found;
3608 Steps.push_back(S);
3609}
3610
3611void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType,
3612 ExprValueKind VK) {
3613 Step S;
3614 switch (VK) {
3615 case VK_PRValue:
3616 S.Kind = SK_CastDerivedToBasePRValue;
3617 break;
3618 case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break;
3619 case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break;
3620 }
3621 S.Type = BaseType;
3622 Steps.push_back(S);
3623}
3624
3625void InitializationSequence::AddReferenceBindingStep(QualType T,
3626 bool BindingTemporary) {
3627 Step S;
3628 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference;
3629 S.Type = T;
3630 Steps.push_back(S);
3631}
3632
3633void InitializationSequence::AddFinalCopy(QualType T) {
3634 Step S;
3635 S.Kind = SK_FinalCopy;
3636 S.Type = T;
3637 Steps.push_back(S);
3638}
3639
3640void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) {
3641 Step S;
3642 S.Kind = SK_ExtraneousCopyToTemporary;
3643 S.Type = T;
3644 Steps.push_back(S);
3645}
3646
3647void
3648InitializationSequence::AddUserConversionStep(FunctionDecl *Function,
3649 DeclAccessPair FoundDecl,
3650 QualType T,
3651 bool HadMultipleCandidates) {
3652 Step S;
3653 S.Kind = SK_UserConversion;
3654 S.Type = T;
3655 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3656 S.Function.Function = Function;
3657 S.Function.FoundDecl = FoundDecl;
3658 Steps.push_back(S);
3659}
3660
3661void InitializationSequence::AddQualificationConversionStep(QualType Ty,
3662 ExprValueKind VK) {
3663 Step S;
3664 S.Kind = SK_QualificationConversionPRValue; // work around a gcc warning
3665 switch (VK) {
3666 case VK_PRValue:
3667 S.Kind = SK_QualificationConversionPRValue;
3668 break;
3669 case VK_XValue:
3670 S.Kind = SK_QualificationConversionXValue;
3671 break;
3672 case VK_LValue:
3673 S.Kind = SK_QualificationConversionLValue;
3674 break;
3675 }
3676 S.Type = Ty;
3677 Steps.push_back(S);
3678}
3679
3680void InitializationSequence::AddFunctionReferenceConversionStep(QualType Ty) {
3681 Step S;
3682 S.Kind = SK_FunctionReferenceConversion;
3683 S.Type = Ty;
3684 Steps.push_back(S);
3685}
3686
3687void InitializationSequence::AddAtomicConversionStep(QualType Ty) {
3688 Step S;
3689 S.Kind = SK_AtomicConversion;
3690 S.Type = Ty;
3691 Steps.push_back(S);
3692}
3693
3694void InitializationSequence::AddConversionSequenceStep(
3695 const ImplicitConversionSequence &ICS, QualType T,
3696 bool TopLevelOfInitList) {
3697 Step S;
3698 S.Kind = TopLevelOfInitList ? SK_ConversionSequenceNoNarrowing
3699 : SK_ConversionSequence;
3700 S.Type = T;
3701 S.ICS = new ImplicitConversionSequence(ICS);
3702 Steps.push_back(S);
3703}
3704
3705void InitializationSequence::AddListInitializationStep(QualType T) {
3706 Step S;
3707 S.Kind = SK_ListInitialization;
3708 S.Type = T;
3709 Steps.push_back(S);
3710}
3711
3712void InitializationSequence::AddConstructorInitializationStep(
3713 DeclAccessPair FoundDecl, CXXConstructorDecl *Constructor, QualType T,
3714 bool HadMultipleCandidates, bool FromInitList, bool AsInitList) {
3715 Step S;
3716 S.Kind = FromInitList ? AsInitList ? SK_StdInitializerListConstructorCall
3717 : SK_ConstructorInitializationFromList
3718 : SK_ConstructorInitialization;
3719 S.Type = T;
3720 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3721 S.Function.Function = Constructor;
3722 S.Function.FoundDecl = FoundDecl;
3723 Steps.push_back(S);
3724}
3725
3726void InitializationSequence::AddZeroInitializationStep(QualType T) {
3727 Step S;
3728 S.Kind = SK_ZeroInitialization;
3729 S.Type = T;
3730 Steps.push_back(S);
3731}
3732
3733void InitializationSequence::AddCAssignmentStep(QualType T) {
3734 Step S;
3735 S.Kind = SK_CAssignment;
3736 S.Type = T;
3737 Steps.push_back(S);
3738}
3739
3740void InitializationSequence::AddStringInitStep(QualType T) {
3741 Step S;
3742 S.Kind = SK_StringInit;
3743 S.Type = T;
3744 Steps.push_back(S);
3745}
3746
3747void InitializationSequence::AddObjCObjectConversionStep(QualType T) {
3748 Step S;
3749 S.Kind = SK_ObjCObjectConversion;
3750 S.Type = T;
3751 Steps.push_back(S);
3752}
3753
3754void InitializationSequence::AddArrayInitStep(QualType T, bool IsGNUExtension) {
3755 Step S;
3756 S.Kind = IsGNUExtension ? SK_GNUArrayInit : SK_ArrayInit;
3757 S.Type = T;
3758 Steps.push_back(S);
3759}
3760
3761void InitializationSequence::AddArrayInitLoopStep(QualType T, QualType EltT) {
3762 Step S;
3763 S.Kind = SK_ArrayLoopIndex;
3764 S.Type = EltT;
3765 Steps.insert(Steps.begin(), S);
3766
3767 S.Kind = SK_ArrayLoopInit;
3768 S.Type = T;
3769 Steps.push_back(S);
3770}
3771
3772void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) {
3773 Step S;
3774 S.Kind = SK_ParenthesizedArrayInit;
3775 S.Type = T;
3776 Steps.push_back(S);
3777}
3778
3779void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type,
3780 bool shouldCopy) {
3781 Step s;
3782 s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore
3783 : SK_PassByIndirectRestore);
3784 s.Type = type;
3785 Steps.push_back(s);
3786}
3787
3788void InitializationSequence::AddProduceObjCObjectStep(QualType T) {
3789 Step S;
3790 S.Kind = SK_ProduceObjCObject;
3791 S.Type = T;
3792 Steps.push_back(S);
3793}
3794
3795void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) {
3796 Step S;
3797 S.Kind = SK_StdInitializerList;
3798 S.Type = T;
3799 Steps.push_back(S);
3800}
3801
3802void InitializationSequence::AddOCLSamplerInitStep(QualType T) {
3803 Step S;
3804 S.Kind = SK_OCLSamplerInit;
3805 S.Type = T;
3806 Steps.push_back(S);
3807}
3808
3809void InitializationSequence::AddOCLZeroOpaqueTypeStep(QualType T) {
3810 Step S;
3811 S.Kind = SK_OCLZeroOpaqueType;
3812 S.Type = T;
3813 Steps.push_back(S);
3814}
3815
3816void InitializationSequence::RewrapReferenceInitList(QualType T,
3817 InitListExpr *Syntactic) {
3818 assert(Syntactic->getNumInits() == 1 &&(static_cast <bool> (Syntactic->getNumInits() == 1 &&
"Can only rewrap trivial init lists.") ? void (0) : __assert_fail
("Syntactic->getNumInits() == 1 && \"Can only rewrap trivial init lists.\""
, "clang/lib/Sema/SemaInit.cpp", 3819, __extension__ __PRETTY_FUNCTION__
))
3819 "Can only rewrap trivial init lists.")(static_cast <bool> (Syntactic->getNumInits() == 1 &&
"Can only rewrap trivial init lists.") ? void (0) : __assert_fail
("Syntactic->getNumInits() == 1 && \"Can only rewrap trivial init lists.\""
, "clang/lib/Sema/SemaInit.cpp", 3819, __extension__ __PRETTY_FUNCTION__
))
;
3820 Step S;
3821 S.Kind = SK_UnwrapInitList;
3822 S.Type = Syntactic->getInit(0)->getType();
3823 Steps.insert(Steps.begin(), S);
3824
3825 S.Kind = SK_RewrapInitList;
3826 S.Type = T;
3827 S.WrappingSyntacticList = Syntactic;
3828 Steps.push_back(S);
3829}
3830
3831void InitializationSequence::SetOverloadFailure(FailureKind Failure,
3832 OverloadingResult Result) {
3833 setSequenceKind(FailedSequence);
3834 this->Failure = Failure;
3835 this->FailedOverloadResult = Result;
3836}
3837
3838//===----------------------------------------------------------------------===//
3839// Attempt initialization
3840//===----------------------------------------------------------------------===//
3841
3842/// Tries to add a zero initializer. Returns true if that worked.
3843static bool
3844maybeRecoverWithZeroInitialization(Sema &S, InitializationSequence &Sequence,
3845 const InitializedEntity &Entity) {
3846 if (Entity.getKind() != InitializedEntity::EK_Variable)
3847 return false;
3848
3849 VarDecl *VD = cast<VarDecl>(Entity.getDecl());
3850 if (VD->getInit() || VD->getEndLoc().isMacroID())
3851 return false;
3852
3853 QualType VariableTy = VD->getType().getCanonicalType();
3854 SourceLocation Loc = S.getLocForEndOfToken(VD->getEndLoc());
3855 std::string Init = S.getFixItZeroInitializerForType(VariableTy, Loc);
3856 if (!Init.empty()) {
3857 Sequence.AddZeroInitializationStep(Entity.getType());
3858 Sequence.SetZeroInitializationFixit(Init, Loc);
3859 return true;
3860 }
3861 return false;
3862}
3863
3864static void MaybeProduceObjCObject(Sema &S,
3865 InitializationSequence &Sequence,
3866 const InitializedEntity &Entity) {
3867 if (!S.getLangOpts().ObjCAutoRefCount) return;
3868
3869 /// When initializing a parameter, produce the value if it's marked
3870 /// __attribute__((ns_consumed)).
3871 if (Entity.isParameterKind()) {
3872 if (!Entity.isParameterConsumed())
3873 return;
3874
3875 assert(Entity.getType()->isObjCRetainableType() &&(static_cast <bool> (Entity.getType()->isObjCRetainableType
() && "consuming an object of unretainable type?") ? void
(0) : __assert_fail ("Entity.getType()->isObjCRetainableType() && \"consuming an object of unretainable type?\""
, "clang/lib/Sema/SemaInit.cpp", 3876, __extension__ __PRETTY_FUNCTION__
))
3876 "consuming an object of unretainable type?")(static_cast <bool> (Entity.getType()->isObjCRetainableType
() && "consuming an object of unretainable type?") ? void
(0) : __assert_fail ("Entity.getType()->isObjCRetainableType() && \"consuming an object of unretainable type?\""
, "clang/lib/Sema/SemaInit.cpp", 3876, __extension__ __PRETTY_FUNCTION__
))
;
3877 Sequence.AddProduceObjCObjectStep(Entity.getType());
3878
3879 /// When initializing a return value, if the return type is a
3880 /// retainable type, then returns need to immediately retain the
3881 /// object. If an autorelease is required, it will be done at the
3882 /// last instant.
3883 } else if (Entity.getKind() == InitializedEntity::EK_Result ||
3884 Entity.getKind() == InitializedEntity::EK_StmtExprResult) {
3885 if (!Entity.getType()->isObjCRetainableType())
3886 return;
3887
3888 Sequence.AddProduceObjCObjectStep(Entity.getType());
3889 }
3890}
3891
3892static void TryListInitialization(Sema &S,
3893 const InitializedEntity &Entity,
3894 const InitializationKind &Kind,
3895 InitListExpr *InitList,
3896 InitializationSequence &Sequence,
3897 bool TreatUnavailableAsInvalid);
3898
3899/// When initializing from init list via constructor, handle
3900/// initialization of an object of type std::initializer_list<T>.
3901///
3902/// \return true if we have handled initialization of an object of type
3903/// std::initializer_list<T>, false otherwise.
3904static bool TryInitializerListConstruction(Sema &S,
3905 InitListExpr *List,
3906 QualType DestType,
3907 InitializationSequence &Sequence,
3908 bool TreatUnavailableAsInvalid) {
3909 QualType E;
3910 if (!S.isStdInitializerList(DestType, &E))
3911 return false;
3912
3913 if (!S.isCompleteType(List->getExprLoc(), E)) {
3914 Sequence.setIncompleteTypeFailure(E);
3915 return true;
3916 }
3917
3918 // Try initializing a temporary array from the init list.
3919 QualType ArrayType = S.Context.getConstantArrayType(
3920 E.withConst(),
3921 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
3922 List->getNumInits()),
3923 nullptr, clang::ArrayType::Normal, 0);
3924 InitializedEntity HiddenArray =
3925 InitializedEntity::InitializeTemporary(ArrayType);
3926 InitializationKind Kind = InitializationKind::CreateDirectList(
3927 List->getExprLoc(), List->getBeginLoc(), List->getEndLoc());
3928 TryListInitialization(S, HiddenArray, Kind, List, Sequence,
3929 TreatUnavailableAsInvalid);
3930 if (Sequence)
3931 Sequence.AddStdInitializerListConstructionStep(DestType);
3932 return true;
3933}
3934
3935/// Determine if the constructor has the signature of a copy or move
3936/// constructor for the type T of the class in which it was found. That is,
3937/// determine if its first parameter is of type T or reference to (possibly
3938/// cv-qualified) T.
3939static bool hasCopyOrMoveCtorParam(ASTContext &Ctx,
3940 const ConstructorInfo &Info) {
3941 if (Info.Constructor->getNumParams() == 0)
3942 return false;
3943
3944 QualType ParmT =
3945 Info.Constructor->getParamDecl(0)->getType().getNonReferenceType();
3946 QualType ClassT =
3947 Ctx.getRecordType(cast<CXXRecordDecl>(Info.FoundDecl->getDeclContext()));
3948
3949 return Ctx.hasSameUnqualifiedType(ParmT, ClassT);
3950}
3951
3952static OverloadingResult
3953ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc,
3954 MultiExprArg Args,
3955 OverloadCandidateSet &CandidateSet,
3956 QualType DestType,
3957 DeclContext::lookup_result Ctors,
3958 OverloadCandidateSet::iterator &Best,
3959 bool CopyInitializing, bool AllowExplicit,
3960 bool OnlyListConstructors, bool IsListInit,
3961 bool SecondStepOfCopyInit = false) {
3962 CandidateSet.clear(OverloadCandidateSet::CSK_InitByConstructor);
3963 CandidateSet.setDestAS(DestType.getQualifiers().getAddressSpace());
3964
3965 for (NamedDecl *D : Ctors) {
3966 auto Info = getConstructorInfo(D);
3967 if (!Info.Constructor || Info.Constructor->isInvalidDecl())
3968 continue;
3969
3970 if (OnlyListConstructors && !S.isInitListConstructor(Info.Constructor))
3971 continue;
3972
3973 // C++11 [over.best.ics]p4:
3974 // ... and the constructor or user-defined conversion function is a
3975 // candidate by
3976 // - 13.3.1.3, when the argument is the temporary in the second step
3977 // of a class copy-initialization, or
3978 // - 13.3.1.4, 13.3.1.5, or 13.3.1.6 (in all cases), [not handled here]
3979 // - the second phase of 13.3.1.7 when the initializer list has exactly
3980 // one element that is itself an initializer list, and the target is
3981 // the first parameter of a constructor of class X, and the conversion
3982 // is to X or reference to (possibly cv-qualified X),
3983 // user-defined conversion sequences are not considered.
3984 bool SuppressUserConversions =
3985 SecondStepOfCopyInit ||
3986 (IsListInit && Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
3987 hasCopyOrMoveCtorParam(S.Context, Info));
3988
3989 if (Info.ConstructorTmpl)
3990 S.AddTemplateOverloadCandidate(
3991 Info.ConstructorTmpl, Info.FoundDecl,
3992 /*ExplicitArgs*/ nullptr, Args, CandidateSet, SuppressUserConversions,
3993 /*PartialOverloading=*/false, AllowExplicit);
3994 else {
3995 // C++ [over.match.copy]p1:
3996 // - When initializing a temporary to be bound to the first parameter
3997 // of a constructor [for type T] that takes a reference to possibly
3998 // cv-qualified T as its first argument, called with a single
3999 // argument in the context of direct-initialization, explicit
4000 // conversion functions are also considered.
4001 // FIXME: What if a constructor template instantiates to such a signature?
4002 bool AllowExplicitConv = AllowExplicit && !CopyInitializing &&
4003 Args.size() == 1 &&
4004 hasCopyOrMoveCtorParam(S.Context, Info);
4005 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl, Args,
4006 CandidateSet, SuppressUserConversions,
4007 /*PartialOverloading=*/false, AllowExplicit,
4008 AllowExplicitConv);
4009 }
4010 }
4011
4012 // FIXME: Work around a bug in C++17 guaranteed copy elision.
4013 //
4014 // When initializing an object of class type T by constructor
4015 // ([over.match.ctor]) or by list-initialization ([over.match.list])
4016 // from a single expression of class type U, conversion functions of
4017 // U that convert to the non-reference type cv T are candidates.
4018 // Explicit conversion functions are only candidates during
4019 // direct-initialization.
4020 //
4021 // Note: SecondStepOfCopyInit is only ever true in this case when
4022 // evaluating whether to produce a C++98 compatibility warning.
4023 if (S.getLangOpts().CPlusPlus17 && Args.size() == 1 &&
4024 !SecondStepOfCopyInit) {
4025 Expr *Initializer = Args[0];
4026 auto *SourceRD = Initializer->getType()->getAsCXXRecordDecl();
4027 if (SourceRD && S.isCompleteType(DeclLoc, Initializer->getType())) {
4028 const auto &Conversions = SourceRD->getVisibleConversionFunctions();
4029 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4030 NamedDecl *D = *I;
4031 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4032 D = D->getUnderlyingDecl();
4033
4034 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
4035 CXXConversionDecl *Conv;
4036 if (ConvTemplate)
4037 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4038 else
4039 Conv = cast<CXXConversionDecl>(D);
4040
4041 if (ConvTemplate)
4042 S.AddTemplateConversionCandidate(
4043 ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
4044 CandidateSet, AllowExplicit, AllowExplicit,
4045 /*AllowResultConversion*/ false);
4046 else
4047 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Initializer,
4048 DestType, CandidateSet, AllowExplicit,
4049 AllowExplicit,
4050 /*AllowResultConversion*/ false);
4051 }
4052 }
4053 }
4054
4055 // Perform overload resolution and return the result.
4056 return CandidateSet.BestViableFunction(S, DeclLoc, Best);
4057}
4058
4059/// Attempt initialization by constructor (C++ [dcl.init]), which
4060/// enumerates the constructors of the initialized entity and performs overload
4061/// resolution to select the best.
4062/// \param DestType The destination class type.
4063/// \param DestArrayType The destination type, which is either DestType or
4064/// a (possibly multidimensional) array of DestType.
4065/// \param IsListInit Is this list-initialization?
4066/// \param IsInitListCopy Is this non-list-initialization resulting from a
4067/// list-initialization from {x} where x is the same
4068/// type as the entity?
4069static void TryConstructorInitialization(Sema &S,
4070 const InitializedEntity &Entity,
4071 const InitializationKind &Kind,
4072 MultiExprArg Args, QualType DestType,
4073 QualType DestArrayType,
4074 InitializationSequence &Sequence,
4075 bool IsListInit = false,
4076 bool IsInitListCopy = false) {
4077 assert(((!IsListInit && !IsInitListCopy) ||(static_cast <bool> (((!IsListInit && !IsInitListCopy
) || (Args.size() == 1 && isa<InitListExpr>(Args
[0]))) && "IsListInit/IsInitListCopy must come with a single initializer list "
"argument.") ? void (0) : __assert_fail ("((!IsListInit && !IsInitListCopy) || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && \"IsListInit/IsInitListCopy must come with a single initializer list \" \"argument.\""
, "clang/lib/Sema/SemaInit.cpp", 4080, __extension__ __PRETTY_FUNCTION__
))
4078 (Args.size() == 1 && isa<InitListExpr>(Args[0]))) &&(static_cast <bool> (((!IsListInit && !IsInitListCopy
) || (Args.size() == 1 && isa<InitListExpr>(Args
[0]))) && "IsListInit/IsInitListCopy must come with a single initializer list "
"argument.") ? void (0) : __assert_fail ("((!IsListInit && !IsInitListCopy) || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && \"IsListInit/IsInitListCopy must come with a single initializer list \" \"argument.\""
, "clang/lib/Sema/SemaInit.cpp", 4080, __extension__ __PRETTY_FUNCTION__
))
4079 "IsListInit/IsInitListCopy must come with a single initializer list "(static_cast <bool> (((!IsListInit && !IsInitListCopy
) || (Args.size() == 1 && isa<InitListExpr>(Args
[0]))) && "IsListInit/IsInitListCopy must come with a single initializer list "
"argument.") ? void (0) : __assert_fail ("((!IsListInit && !IsInitListCopy) || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && \"IsListInit/IsInitListCopy must come with a single initializer list \" \"argument.\""
, "clang/lib/Sema/SemaInit.cpp", 4080, __extension__ __PRETTY_FUNCTION__
))
4080 "argument.")(static_cast <bool> (((!IsListInit && !IsInitListCopy
) || (Args.size() == 1 && isa<InitListExpr>(Args
[0]))) && "IsListInit/IsInitListCopy must come with a single initializer list "
"argument.") ? void (0) : __assert_fail ("((!IsListInit && !IsInitListCopy) || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && \"IsListInit/IsInitListCopy must come with a single initializer list \" \"argument.\""
, "clang/lib/Sema/SemaInit.cpp", 4080, __extension__ __PRETTY_FUNCTION__
))
;
4081 InitListExpr *ILE =
4082 (IsListInit || IsInitListCopy) ? cast<InitListExpr>(Args[0]) : nullptr;
4083 MultiExprArg UnwrappedArgs =
4084 ILE ? MultiExprArg(ILE->getInits(), ILE->getNumInits()) : Args;
4085
4086 // The type we're constructing needs to be complete.
4087 if (!S.isCompleteType(Kind.getLocation(), DestType)) {
4088 Sequence.setIncompleteTypeFailure(DestType);
4089 return;
4090 }
4091
4092 // C++17 [dcl.init]p17:
4093 // - If the initializer expression is a prvalue and the cv-unqualified
4094 // version of the source type is the same class as the class of the
4095 // destination, the initializer expression is used to initialize the
4096 // destination object.
4097 // Per DR (no number yet), this does not apply when initializing a base
4098 // class or delegating to another constructor from a mem-initializer.
4099 // ObjC++: Lambda captured by the block in the lambda to block conversion
4100 // should avoid copy elision.
4101 if (S.getLangOpts().CPlusPlus17 &&
4102 Entity.getKind() != InitializedEntity::EK_Base &&
4103 Entity.getKind() != InitializedEntity::EK_Delegating &&
4104 Entity.getKind() !=
4105 InitializedEntity::EK_LambdaToBlockConversionBlockElement &&
4106 UnwrappedArgs.size() == 1 && UnwrappedArgs[0]->isPRValue() &&
4107 S.Context.hasSameUnqualifiedType(UnwrappedArgs[0]->getType(), DestType)) {
4108 // Convert qualifications if necessary.
4109 Sequence.AddQualificationConversionStep(DestType, VK_PRValue);
4110 if (ILE)
4111 Sequence.RewrapReferenceInitList(DestType, ILE);
4112 return;
4113 }
4114
4115 const RecordType *DestRecordType = DestType->getAs<RecordType>();
4116 assert(DestRecordType && "Constructor initialization requires record type")(static_cast <bool> (DestRecordType && "Constructor initialization requires record type"
) ? void (0) : __assert_fail ("DestRecordType && \"Constructor initialization requires record type\""
, "clang/lib/Sema/SemaInit.cpp", 4116, __extension__ __PRETTY_FUNCTION__
))
;
4117 CXXRecordDecl *DestRecordDecl
4118 = cast<CXXRecordDecl>(DestRecordType->getDecl());
4119
4120 // Build the candidate set directly in the initialization sequence
4121 // structure, so that it will persist if we fail.
4122 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4123
4124 // Determine whether we are allowed to call explicit constructors or
4125 // explicit conversion operators.
4126 bool AllowExplicit = Kind.AllowExplicit() || IsListInit;
4127 bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy;
4128
4129 // - Otherwise, if T is a class type, constructors are considered. The
4130 // applicable constructors are enumerated, and the best one is chosen
4131 // through overload resolution.
4132 DeclContext::lookup_result Ctors = S.LookupConstructors(DestRecordDecl);
4133
4134 OverloadingResult Result = OR_No_Viable_Function;
4135 OverloadCandidateSet::iterator Best;
4136 bool AsInitializerList = false;
4137
4138 // C++11 [over.match.list]p1, per DR1467:
4139 // When objects of non-aggregate type T are list-initialized, such that
4140 // 8.5.4 [dcl.init.list] specifies that overload resolution is performed
4141 // according to the rules in this section, overload resolution selects
4142 // the constructor in two phases:
4143 //
4144 // - Initially, the candidate functions are the initializer-list
4145 // constructors of the class T and the argument list consists of the
4146 // initializer list as a single argument.
4147 if (IsListInit) {
4148 AsInitializerList = true;
4149
4150 // If the initializer list has no elements and T has a default constructor,
4151 // the first phase is omitted.
4152 if (!(UnwrappedArgs.empty() && S.LookupDefaultConstructor(DestRecordDecl)))
4153 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args,
4154 CandidateSet, DestType, Ctors, Best,
4155 CopyInitialization, AllowExplicit,
4156 /*OnlyListConstructors=*/true,
4157 IsListInit);
4158 }
4159
4160 // C++11 [over.match.list]p1:
4161 // - If no viable initializer-list constructor is found, overload resolution
4162 // is performed again, where the candidate functions are all the
4163 // constructors of the class T and the argument list consists of the
4164 // elements of the initializer list.
4165 if (Result == OR_No_Viable_Function) {
4166 AsInitializerList = false;
4167 Result = ResolveConstructorOverload(S, Kind.getLocation(), UnwrappedArgs,
4168 CandidateSet, DestType, Ctors, Best,
4169 CopyInitialization, AllowExplicit,
4170 /*OnlyListConstructors=*/false,
4171 IsListInit);
4172 }
4173 if (Result) {
4174 Sequence.SetOverloadFailure(
4175 IsListInit ? InitializationSequence::FK_ListConstructorOverloadFailed
4176 : InitializationSequence::FK_ConstructorOverloadFailed,
4177 Result);
4178
4179 if (Result != OR_Deleted)
4180 return;
4181 }
4182
4183 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4184
4185 // In C++17, ResolveConstructorOverload can select a conversion function
4186 // instead of a constructor.
4187 if (auto *CD = dyn_cast<CXXConversionDecl>(Best->Function)) {
4188 // Add the user-defined conversion step that calls the conversion function.
4189 QualType ConvType = CD->getConversionType();
4190 assert(S.Context.hasSameUnqualifiedType(ConvType, DestType) &&(static_cast <bool> (S.Context.hasSameUnqualifiedType(ConvType
, DestType) && "should not have selected this conversion function"
) ? void (0) : __assert_fail ("S.Context.hasSameUnqualifiedType(ConvType, DestType) && \"should not have selected this conversion function\""
, "clang/lib/Sema/SemaInit.cpp", 4191, __extension__ __PRETTY_FUNCTION__
))
4191 "should not have selected this conversion function")(static_cast <bool> (S.Context.hasSameUnqualifiedType(ConvType
, DestType) && "should not have selected this conversion function"
) ? void (0) : __assert_fail ("S.Context.hasSameUnqualifiedType(ConvType, DestType) && \"should not have selected this conversion function\""
, "clang/lib/Sema/SemaInit.cpp", 4191, __extension__ __PRETTY_FUNCTION__
))
;
4192 Sequence.AddUserConversionStep(CD, Best->FoundDecl, ConvType,
4193 HadMultipleCandidates);
4194 if (!S.Context.hasSameType(ConvType, DestType))
4195 Sequence.AddQualificationConversionStep(DestType, VK_PRValue);
4196 if (IsListInit)
4197 Sequence.RewrapReferenceInitList(Entity.getType(), ILE);
4198 return;
4199 }
4200
4201 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
4202 if (Result != OR_Deleted) {
4203 // C++11 [dcl.init]p6:
4204 // If a program calls for the default initialization of an object
4205 // of a const-qualified type T, T shall be a class type with a
4206 // user-provided default constructor.
4207 // C++ core issue 253 proposal:
4208 // If the implicit default constructor initializes all subobjects, no
4209 // initializer should be required.
4210 // The 253 proposal is for example needed to process libstdc++ headers
4211 // in 5.x.
4212 if (Kind.getKind() == InitializationKind::IK_Default &&
4213 Entity.getType().isConstQualified()) {
4214 if (!CtorDecl->getParent()->allowConstDefaultInit()) {
4215 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
4216 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
4217 return;
4218 }
4219 }
4220
4221 // C++11 [over.match.list]p1:
4222 // In copy-list-initialization, if an explicit constructor is chosen, the
4223 // initializer is ill-formed.
4224 if (IsListInit && !Kind.AllowExplicit() && CtorDecl->isExplicit()) {
4225 Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor);
4226 return;
4227 }
4228 }
4229
4230 // [class.copy.elision]p3:
4231 // In some copy-initialization contexts, a two-stage overload resolution
4232 // is performed.
4233 // If the first overload resolution selects a deleted function, we also
4234 // need the initialization sequence to decide whether to perform the second
4235 // overload resolution.
4236 // For deleted functions in other contexts, there is no need to get the
4237 // initialization sequence.
4238 if (Result == OR_Deleted && Kind.getKind() != InitializationKind::IK_Copy)
4239 return;
4240
4241 // Add the constructor initialization step. Any cv-qualification conversion is
4242 // subsumed by the initialization.
4243 Sequence.AddConstructorInitializationStep(
4244 Best->FoundDecl, CtorDecl, DestArrayType, HadMultipleCandidates,
4245 IsListInit | IsInitListCopy, AsInitializerList);
4246}
4247
4248static bool
4249ResolveOverloadedFunctionForReferenceBinding(Sema &S,
4250 Expr *Initializer,
4251 QualType &SourceType,
4252 QualType &UnqualifiedSourceType,
4253 QualType UnqualifiedTargetType,
4254 InitializationSequence &Sequence) {
4255 if (S.Context.getCanonicalType(UnqualifiedSourceType) ==
4256 S.Context.OverloadTy) {
4257 DeclAccessPair Found;
4258 bool HadMultipleCandidates = false;
4259 if (FunctionDecl *Fn
4260 = S.ResolveAddressOfOverloadedFunction(Initializer,
4261 UnqualifiedTargetType,
4262 false, Found,
4263 &HadMultipleCandidates)) {
4264 Sequence.AddAddressOverloadResolutionStep(Fn, Found,
4265 HadMultipleCandidates);
4266 SourceType = Fn->getType();
4267 UnqualifiedSourceType = SourceType.getUnqualifiedType();
4268 } else if (!UnqualifiedTargetType->isRecordType()) {
4269 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4270 return true;
4271 }
4272 }
4273 return false;
4274}
4275
4276static void TryReferenceInitializationCore(Sema &S,
4277 const InitializedEntity &Entity,
4278 const InitializationKind &Kind,
4279 Expr *Initializer,
4280 QualType cv1T1, QualType T1,
4281 Qualifiers T1Quals,
4282 QualType cv2T2, QualType T2,
4283 Qualifiers T2Quals,
4284 InitializationSequence &Sequence);
4285
4286static void TryValueInitialization(Sema &S,
4287 const InitializedEntity &Entity,
4288 const InitializationKind &Kind,
4289 InitializationSequence &Sequence,
4290 InitListExpr *InitList = nullptr);
4291
4292/// Attempt list initialization of a reference.
4293static void TryReferenceListInitialization(Sema &S,
4294 const InitializedEntity &Entity,
4295 const InitializationKind &Kind,
4296 InitListExpr *InitList,
4297 InitializationSequence &Sequence,
4298 bool TreatUnavailableAsInvalid) {
4299 // First, catch C++03 where this isn't possible.
4300 if (!S.getLangOpts().CPlusPlus11) {
4301 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
4302 return;
4303 }
4304 // Can't reference initialize a compound literal.
4305 if (Entity.getKind() == InitializedEntity::EK_CompoundLiteralInit) {
4306 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
4307 return;
4308 }
4309
4310 QualType DestType = Entity.getType();
4311 QualType cv1T1 = DestType->castAs<ReferenceType>()->getPointeeType();
4312 Qualifiers T1Quals;
4313 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
4314
4315 // Reference initialization via an initializer list works thus:
4316 // If the initializer list consists of a single element that is
4317 // reference-related to the referenced type, bind directly to that element
4318 // (possibly creating temporaries).
4319 // Otherwise, initialize a temporary with the initializer list and
4320 // bind to that.
4321 if (InitList->getNumInits() == 1) {
4322 Expr *Initializer = InitList->getInit(0);
4323 QualType cv2T2 = S.getCompletedType(Initializer);
4324 Qualifiers T2Quals;
4325 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
4326
4327 // If this fails, creating a temporary wouldn't work either.
4328 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
4329 T1, Sequence))
4330 return;
4331
4332 SourceLocation DeclLoc = Initializer->getBeginLoc();
4333 Sema::ReferenceCompareResult RefRelationship
4334 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2);
4335 if (RefRelationship >= Sema::Ref_Related) {
4336 // Try to bind the reference here.
4337 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
4338 T1Quals, cv2T2, T2, T2Quals, Sequence);
4339 if (Sequence)
4340 Sequence.RewrapReferenceInitList(cv1T1, InitList);
4341 return;
4342 }
4343
4344 // Update the initializer if we've resolved an overloaded function.
4345 if (Sequence.step_begin() != Sequence.step_end())
4346 Sequence.RewrapReferenceInitList(cv1T1, InitList);
4347 }
4348 // Perform address space compatibility check.
4349 QualType cv1T1IgnoreAS = cv1T1;
4350 if (T1Quals.hasAddressSpace()) {
4351 Qualifiers T2Quals;
4352 (void)S.Context.getUnqualifiedArrayType(InitList->getType(), T2Quals);
4353 if (!T1Quals.isAddressSpaceSupersetOf(T2Quals)) {
4354 Sequence.SetFailed(
4355 InitializationSequence::FK_ReferenceInitDropsQualifiers);
4356 return;
4357 }
4358 // Ignore address space of reference type at this point and perform address
4359 // space conversion after the reference binding step.
4360 cv1T1IgnoreAS =
4361 S.Context.getQualifiedType(T1, T1Quals.withoutAddressSpace());
4362 }
4363 // Not reference-related. Create a temporary and bind to that.
4364 InitializedEntity TempEntity =
4365 InitializedEntity::InitializeTemporary(cv1T1IgnoreAS);
4366
4367 TryListInitialization(S, TempEntity, Kind, InitList, Sequence,
4368 TreatUnavailableAsInvalid);
4369 if (Sequence) {
4370 if (DestType->isRValueReferenceType() ||
4371 (T1Quals.hasConst() && !T1Quals.hasVolatile())) {
4372 Sequence.AddReferenceBindingStep(cv1T1IgnoreAS,
4373 /*BindingTemporary=*/true);
4374 if (T1Quals.hasAddressSpace())
4375 Sequence.AddQualificationConversionStep(
4376 cv1T1, DestType->isRValueReferenceType() ? VK_XValue : VK_LValue);
4377 } else
4378 Sequence.SetFailed(
4379 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
4380 }
4381}
4382
4383/// Attempt list initialization (C++0x [dcl.init.list])
4384static void TryListInitialization(Sema &S,
4385 const InitializedEntity &Entity,
4386 const InitializationKind &Kind,
4387 InitListExpr *InitList,
4388 InitializationSequence &Sequence,
4389 bool TreatUnavailableAsInvalid) {
4390 QualType DestType = Entity.getType();
4391
4392 // C++ doesn't allow scalar initialization with more than one argument.
4393 // But C99 complex numbers are scalars and it makes sense there.
4394 if (S.getLangOpts().CPlusPlus && DestType->isScalarType() &&
4395 !DestType->isAnyComplexType() && InitList->getNumInits() > 1) {
4396 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar);
4397 return;
4398 }
4399 if (DestType->isReferenceType()) {
4400 TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence,
4401 TreatUnavailableAsInvalid);
4402 return;
4403 }
4404
4405 if (DestType->isRecordType() &&
4406 !S.isCompleteType(InitList->getBeginLoc(), DestType)) {
4407 Sequence.setIncompleteTypeFailure(DestType);
4408 return;
4409 }
4410
4411 // C++11 [dcl.init.list]p3, per DR1467:
4412 // - If T is a class type and the initializer list has a single element of
4413 // type cv U, where U is T or a class derived from T, the object is
4414 // initialized from that element (by copy-initialization for
4415 // copy-list-initialization, or by direct-initialization for
4416 // direct-list-initialization).
4417 // - Otherwise, if T is a character array and the initializer list has a
4418 // single element that is an appropriately-typed string literal
4419 // (8.5.2 [dcl.init.string]), initialization is performed as described
4420 // in that section.
4421 // - Otherwise, if T is an aggregate, [...] (continue below).
4422 if (S.getLangOpts().CPlusPlus11 && InitList->getNumInits() == 1) {
4423 if (DestType->isRecordType()) {
4424 QualType InitType = InitList->getInit(0)->getType();
4425 if (S.Context.hasSameUnqualifiedType(InitType, DestType) ||
4426 S.IsDerivedFrom(InitList->getBeginLoc(), InitType, DestType)) {
4427 Expr *InitListAsExpr = InitList;
4428 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
4429 DestType, Sequence,
4430 /*InitListSyntax*/false,
4431 /*IsInitListCopy*/true);
4432 return;
4433 }
4434 }
4435 if (const ArrayType *DestAT = S.Context.getAsArrayType(DestType)) {
4436 Expr *SubInit[1] = {InitList->getInit(0)};
4437 if (!isa<VariableArrayType>(DestAT) &&
4438 IsStringInit(SubInit[0], DestAT, S.Context) == SIF_None) {
4439 InitializationKind SubKind =
4440 Kind.getKind() == InitializationKind::IK_DirectList
4441 ? InitializationKind::CreateDirect(Kind.getLocation(),
4442 InitList->getLBraceLoc(),
4443 InitList->getRBraceLoc())
4444 : Kind;
4445 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
4446 /*TopLevelOfInitList*/ true,
4447 TreatUnavailableAsInvalid);
4448
4449 // TryStringLiteralInitialization() (in InitializeFrom()) will fail if
4450 // the element is not an appropriately-typed string literal, in which
4451 // case we should proceed as in C++11 (below).
4452 if (Sequence) {
4453 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4454 return;
4455 }
4456 }
4457 }
4458 }
4459
4460 // C++11 [dcl.init.list]p3:
4461 // - If T is an aggregate, aggregate initialization is performed.
4462 if ((DestType->isRecordType() && !DestType->isAggregateType()) ||
4463 (S.getLangOpts().CPlusPlus11 &&
4464 S.isStdInitializerList(DestType, nullptr))) {
4465 if (S.getLangOpts().CPlusPlus11) {
4466 // - Otherwise, if the initializer list has no elements and T is a
4467 // class type with a default constructor, the object is
4468 // value-initialized.
4469 if (InitList->getNumInits() == 0) {
4470 CXXRecordDecl *RD = DestType->getAsCXXRecordDecl();
4471 if (S.LookupDefaultConstructor(RD)) {
4472 TryValueInitialization(S, Entity, Kind, Sequence, InitList);
4473 return;
4474 }
4475 }
4476
4477 // - Otherwise, if T is a specialization of std::initializer_list<E>,
4478 // an initializer_list object constructed [...]
4479 if (TryInitializerListConstruction(S, InitList, DestType, Sequence,
4480 TreatUnavailableAsInvalid))
4481 return;
4482
4483 // - Otherwise, if T is a class type, constructors are considered.
4484 Expr *InitListAsExpr = InitList;
4485 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
4486 DestType, Sequence, /*InitListSyntax*/true);
4487 } else
4488 Sequence.SetFailed(InitializationSequence::FK_InitListBadDestinationType);
4489 return;
4490 }
4491
4492 if (S.getLangOpts().CPlusPlus && !DestType->isAggregateType() &&
4493 InitList->getNumInits() == 1) {
4494 Expr *E = InitList->getInit(0);
4495
4496 // - Otherwise, if T is an enumeration with a fixed underlying type,
4497 // the initializer-list has a single element v, and the initialization
4498 // is direct-list-initialization, the object is initialized with the
4499 // value T(v); if a narrowing conversion is required to convert v to
4500 // the underlying type of T, the program is ill-formed.
4501 auto *ET = DestType->getAs<EnumType>();
4502 if (S.getLangOpts().CPlusPlus17 &&
4503 Kind.getKind() == InitializationKind::IK_DirectList &&
4504 ET && ET->getDecl()->isFixed() &&
4505 !S.Context.hasSameUnqualifiedType(E->getType(), DestType) &&
4506 (E->getType()->isIntegralOrUnscopedEnumerationType() ||
4507 E->getType()->isFloatingType())) {
4508 // There are two ways that T(v) can work when T is an enumeration type.
4509 // If there is either an implicit conversion sequence from v to T or
4510 // a conversion function that can convert from v to T, then we use that.
4511 // Otherwise, if v is of integral, unscoped enumeration, or floating-point
4512 // type, it is converted to the enumeration type via its underlying type.
4513 // There is no overlap possible between these two cases (except when the
4514 // source value is already of the destination type), and the first
4515 // case is handled by the general case for single-element lists below.
4516 ImplicitConversionSequence ICS;
4517 ICS.setStandard();
4518 ICS.Standard.setAsIdentityConversion();
4519 if (!E->isPRValue())
4520 ICS.Standard.First = ICK_Lvalue_To_Rvalue;
4521 // If E is of a floating-point type, then the conversion is ill-formed
4522 // due to narrowing, but go through the motions in order to produce the
4523 // right diagnostic.
4524 ICS.Standard.Second = E->getType()->isFloatingType()
4525 ? ICK_Floating_Integral
4526 : ICK_Integral_Conversion;
4527 ICS.Standard.setFromType(E->getType());
4528 ICS.Standard.setToType(0, E->getType());
4529 ICS.Standard.setToType(1, DestType);
4530 ICS.Standard.setToType(2, DestType);
4531 Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2),
4532 /*TopLevelOfInitList*/true);
4533 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4534 return;
4535 }
4536
4537 // - Otherwise, if the initializer list has a single element of type E
4538 // [...references are handled above...], the object or reference is
4539 // initialized from that element (by copy-initialization for
4540 // copy-list-initialization, or by direct-initialization for
4541 // direct-list-initialization); if a narrowing conversion is required
4542 // to convert the element to T, the program is ill-formed.
4543 //
4544 // Per core-24034, this is direct-initialization if we were performing
4545 // direct-list-initialization and copy-initialization otherwise.
4546 // We can't use InitListChecker for this, because it always performs
4547 // copy-initialization. This only matters if we might use an 'explicit'
4548 // conversion operator, or for the special case conversion of nullptr_t to
4549 // bool, so we only need to handle those cases.
4550 //
4551 // FIXME: Why not do this in all cases?
4552 Expr *Init = InitList->getInit(0);
4553 if (Init->getType()->isRecordType() ||
4554 (Init->getType()->isNullPtrType() && DestType->isBooleanType())) {
4555 InitializationKind SubKind =
4556 Kind.getKind() == InitializationKind::IK_DirectList
4557 ? InitializationKind::CreateDirect(Kind.getLocation(),
4558 InitList->getLBraceLoc(),
4559 InitList->getRBraceLoc())
4560 : Kind;
4561 Expr *SubInit[1] = { Init };
4562 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
4563 /*TopLevelOfInitList*/true,
4564 TreatUnavailableAsInvalid);
4565 if (Sequence)
4566 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4567 return;
4568 }
4569 }
4570
4571 InitListChecker CheckInitList(S, Entity, InitList,
4572 DestType, /*VerifyOnly=*/true, TreatUnavailableAsInvalid);
4573 if (CheckInitList.HadError()) {
4574 Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed);
4575 return;
4576 }
4577
4578 // Add the list initialization step with the built init list.
4579 Sequence.AddListInitializationStep(DestType);
4580}
4581
4582/// Try a reference initialization that involves calling a conversion
4583/// function.
4584static OverloadingResult TryRefInitWithConversionFunction(
4585 Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind,
4586 Expr *Initializer, bool AllowRValues, bool IsLValueRef,
4587 InitializationSequence &Sequence) {
4588 QualType DestType = Entity.getType();
4589 QualType cv1T1 = DestType->castAs<ReferenceType>()->getPointeeType();
4590 QualType T1 = cv1T1.getUnqualifiedType();
4591 QualType cv2T2 = Initializer->getType();
4592 QualType T2 = cv2T2.getUnqualifiedType();
4593
4594 assert(!S.CompareReferenceRelationship(Initializer->getBeginLoc(), T1, T2) &&(static_cast <bool> (!S.CompareReferenceRelationship(Initializer
->getBeginLoc(), T1, T2) && "Must have incompatible references when binding via conversion"
) ? void (0) : __assert_fail ("!S.CompareReferenceRelationship(Initializer->getBeginLoc(), T1, T2) && \"Must have incompatible references when binding via conversion\""
, "clang/lib/Sema/SemaInit.cpp", 4595, __extension__ __PRETTY_FUNCTION__
))
4595 "Must have incompatible references when binding via conversion")(static_cast <bool> (!S.CompareReferenceRelationship(Initializer
->getBeginLoc(), T1, T2) && "Must have incompatible references when binding via conversion"
) ? void (0) : __assert_fail ("!S.CompareReferenceRelationship(Initializer->getBeginLoc(), T1, T2) && \"Must have incompatible references when binding via conversion\""
, "clang/lib/Sema/SemaInit.cpp", 4595, __extension__ __PRETTY_FUNCTION__
))
;
4596
4597 // Build the candidate set directly in the initialization sequence
4598 // structure, so that it will persist if we fail.
4599 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4600 CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
4601
4602 // Determine whether we are allowed to call explicit conversion operators.
4603 // Note that none of [over.match.copy], [over.match.conv], nor
4604 // [over.match.ref] permit an explicit constructor to be chosen when
4605 // initializing a reference, not even for direct-initialization.
4606 bool AllowExplicitCtors = false;
4607 bool AllowExplicitConvs = Kind.allowExplicitConversionFunctionsInRefBinding();
4608
4609 const RecordType *T1RecordType = nullptr;
4610 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) &&
4611 S.isCompleteType(Kind.getLocation(), T1)) {
4612 // The type we're converting to is a class type. Enumerate its constructors
4613 // to see if there is a suitable conversion.
4614 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl());
4615
4616 for (NamedDecl *D : S.LookupConstructors(T1RecordDecl)) {
4617 auto Info = getConstructorInfo(D);
4618 if (!Info.Constructor)
4619 continue;
4620
4621 if (!Info.Constructor->isInvalidDecl() &&
4622 Info.Constructor->isConvertingConstructor(/*AllowExplicit*/true)) {
4623 if (Info.ConstructorTmpl)
4624 S.AddTemplateOverloadCandidate(
4625 Info.ConstructorTmpl, Info.FoundDecl,
4626 /*ExplicitArgs*/ nullptr, Initializer, CandidateSet,
4627 /*SuppressUserConversions=*/true,
4628 /*PartialOverloading*/ false, AllowExplicitCtors);
4629 else
4630 S.AddOverloadCandidate(
4631 Info.Constructor, Info.FoundDecl, Initializer, CandidateSet,
4632 /*SuppressUserConversions=*/true,
4633 /*PartialOverloading*/ false, AllowExplicitCtors);
4634 }
4635 }
4636 }
4637 if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl())
4638 return OR_No_Viable_Function;
4639
4640 const RecordType *T2RecordType = nullptr;
4641 if ((T2RecordType = T2->getAs<RecordType>()) &&
4642 S.isCompleteType(Kind.getLocation(), T2)) {
4643 // The type we're converting from is a class type, enumerate its conversion
4644 // functions.
4645 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl());
4646
4647 const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
4648 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4649 NamedDecl *D = *I;
4650 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4651 if (isa<UsingShadowDecl>(D))
4652 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4653
4654 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
4655 CXXConversionDecl *Conv;
4656 if (ConvTemplate)
4657 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4658 else
4659 Conv = cast<CXXConversionDecl>(D);
4660
4661 // If the conversion function doesn't return a reference type,
4662 // it can't be considered for this conversion unless we're allowed to
4663 // consider rvalues.
4664 // FIXME: Do we need to make sure that we only consider conversion
4665 // candidates with reference-compatible results? That might be needed to
4666 // break recursion.
4667 if ((AllowRValues ||
4668 Conv->getConversionType()->isLValueReferenceType())) {
4669 if (ConvTemplate)
4670 S.AddTemplateConversionCandidate(
4671 ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
4672 CandidateSet,
4673 /*AllowObjCConversionOnExplicit=*/false, AllowExplicitConvs);
4674 else
4675 S.AddConversionCandidate(
4676 Conv, I.getPair(), ActingDC, Initializer, DestType, CandidateSet,
4677 /*AllowObjCConversionOnExplicit=*/false, AllowExplicitConvs);
4678 }
4679 }
4680 }
4681 if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl())
4682 return OR_No_Viable_Function;
4683
4684 SourceLocation DeclLoc = Initializer->getBeginLoc();
4685
4686 // Perform overload resolution. If it fails, return the failed result.
4687 OverloadCandidateSet::iterator Best;
4688 if (OverloadingResult Result
4689 = CandidateSet.BestViableFunction(S, DeclLoc, Best))
4690 return Result;
4691
4692 FunctionDecl *Function = Best->Function;
4693 // This is the overload that will be used for this initialization step if we
4694 // use this initialization. Mark it as referenced.
4695 Function->setReferenced();
4696
4697 // Compute the returned type and value kind of the conversion.
4698 QualType cv3T3;
4699 if (isa<CXXConversionDecl>(Function))
4700 cv3T3 = Function->getReturnType();
4701 else
4702 cv3T3 = T1;
4703
4704 ExprValueKind VK = VK_PRValue;
4705 if (cv3T3->isLValueReferenceType())
4706 VK = VK_LValue;
4707 else if (const auto *RRef = cv3T3->getAs<RValueReferenceType>())
4708 VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue;
4709 cv3T3 = cv3T3.getNonLValueExprType(S.Context);
4710
4711 // Add the user-defined conversion step.
4712 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4713 Sequence.AddUserConversionStep(Function, Best->FoundDecl, cv3T3,
4714 HadMultipleCandidates);
4715
4716 // Determine whether we'll need to perform derived-to-base adjustments or
4717 // other conversions.
4718 Sema::ReferenceConversions RefConv;
4719 Sema::ReferenceCompareResult NewRefRelationship =
4720 S.CompareReferenceRelationship(DeclLoc, T1, cv3T3, &RefConv);
4721
4722 // Add the final conversion sequence, if necessary.
4723 if (NewRefRelationship == Sema::Ref_Incompatible) {
4724 assert(!isa<CXXConstructorDecl>(Function) &&(static_cast <bool> (!isa<CXXConstructorDecl>(Function
) && "should not have conversion after constructor") ?
void (0) : __assert_fail ("!isa<CXXConstructorDecl>(Function) && \"should not have conversion after constructor\""
, "clang/lib/Sema/SemaInit.cpp", 4725, __extension__ __PRETTY_FUNCTION__
))
4725 "should not have conversion after constructor")(static_cast <bool> (!isa<CXXConstructorDecl>(Function
) && "should not have conversion after constructor") ?
void (0) : __assert_fail ("!isa<CXXConstructorDecl>(Function) && \"should not have conversion after constructor\""
, "clang/lib/Sema/SemaInit.cpp", 4725, __extension__ __PRETTY_FUNCTION__
))
;
4726
4727 ImplicitConversionSequence ICS;
4728 ICS.setStandard();
4729 ICS.Standard = Best->FinalConversion;
4730 Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2));
4731
4732 // Every implicit conversion results in a prvalue, except for a glvalue
4733 // derived-to-base conversion, which we handle below.
4734 cv3T3 = ICS.Standard.getToType(2);
4735 VK = VK_PRValue;
4736 }
4737
4738 // If the converted initializer is a prvalue, its type T4 is adjusted to
4739 // type "cv1 T4" and the temporary materialization conversion is applied.
4740 //
4741 // We adjust the cv-qualifications to match the reference regardless of
4742 // whether we have a prvalue so that the AST records the change. In this
4743 // case, T4 is "cv3 T3".
4744 QualType cv1T4 = S.Context.getQualifiedType(cv3T3, cv1T1.getQualifiers());
4745 if (cv1T4.getQualifiers() != cv3T3.getQualifiers())
4746 Sequence.AddQualificationConversionStep(cv1T4, VK);
4747 Sequence.AddReferenceBindingStep(cv1T4, VK == VK_PRValue);
4748 VK = IsLValueRef ? VK_LValue : VK_XValue;
4749
4750 if (RefConv & Sema::ReferenceConversions::DerivedToBase)
4751 Sequence.AddDerivedToBaseCastStep(cv1T1, VK);
4752 else if (RefConv & Sema::ReferenceConversions::ObjC)
4753 Sequence.AddObjCObjectConversionStep(cv1T1);
4754 else if (RefConv & Sema::ReferenceConversions::Function)
4755 Sequence.AddFunctionReferenceConversionStep(cv1T1);
4756 else if (RefConv & Sema::ReferenceConversions::Qualification) {
4757 if (!S.Context.hasSameType(cv1T4, cv1T1))
4758 Sequence.AddQualificationConversionStep(cv1T1, VK);
4759 }
4760
4761 return OR_Success;
4762}
4763
4764static void CheckCXX98CompatAccessibleCopy(Sema &S,
4765 const InitializedEntity &Entity,
4766 Expr *CurInitExpr);
4767
4768/// Attempt reference initialization (C++0x [dcl.init.ref])
4769static void TryReferenceInitialization(Sema &S,
4770 const InitializedEntity &Entity,
4771 const InitializationKind &Kind,
4772 Expr *Initializer,
4773 InitializationSequence &Sequence) {
4774 QualType DestType = Entity.getType();
4775 QualType cv1T1 = DestType->castAs<ReferenceType>()->getPointeeType();
4776 Qualifiers T1Quals;
4777 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
4778 QualType cv2T2 = S.getCompletedType(Initializer);
4779 Qualifiers T2Quals;
4780 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
4781
4782 // If the initializer is the address of an overloaded function, try
4783 // to resolve the overloaded function. If all goes well, T2 is the
4784 // type of the resulting function.
4785 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
4786 T1, Sequence))
4787 return;
4788
4789 // Delegate everything else to a subfunction.
4790 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
4791 T1Quals, cv2T2, T2, T2Quals, Sequence);
4792}
4793
4794/// Determine whether an expression is a non-referenceable glvalue (one to
4795/// which a reference can never bind). Attempting to bind a reference to
4796/// such a glvalue will always create a temporary.
4797static bool isNonReferenceableGLValue(Expr *E) {
4798 return E->refersToBitField() || E->refersToVectorElement() ||
4799 E->refersToMatrixElement();
4800}
4801
4802/// Reference initialization without resolving overloaded functions.
4803///
4804/// We also can get here in C if we call a builtin which is declared as
4805/// a function with a parameter of reference type (such as __builtin_va_end()).
4806static void TryReferenceInitializationCore(Sema &S,
4807 const InitializedEntity &Entity,
4808 const InitializationKind &Kind,
4809 Expr *Initializer,
4810 QualType cv1T1, QualType T1,
4811 Qualifiers T1Quals,
4812 QualType cv2T2, QualType T2,
4813 Qualifiers T2Quals,
4814 InitializationSequence &Sequence) {
4815 QualType DestType = Entity.getType();
4816 SourceLocation DeclLoc = Initializer->getBeginLoc();
4817
4818 // Compute some basic properties of the types and the initializer.
4819 bool isLValueRef = DestType->isLValueReferenceType();
4820 bool isRValueRef = !isLValueRef;
4821 Expr::Classification InitCategory = Initializer->Classify(S.Context);
4822
4823 Sema::ReferenceConversions RefConv;
4824 Sema::ReferenceCompareResult RefRelationship =
4825 S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, &RefConv);
4826
4827 // C++0x [dcl.init.ref]p5:
4828 // A reference to type "cv1 T1" is initialized by an expression of type
4829 // "cv2 T2" as follows:
4830 //
4831 // - If the reference is an lvalue reference and the initializer
4832 // expression
4833 // Note the analogous bullet points for rvalue refs to functions. Because
4834 // there are no function rvalues in C++, rvalue refs to functions are treated
4835 // like lvalue refs.
4836 OverloadingResult ConvOvlResult = OR_Success;
4837 bool T1Function = T1->isFunctionType();
4838 if (isLValueRef || T1Function) {
4839 if (InitCategory.isLValue() && !isNonReferenceableGLValue(Initializer) &&
4840 (RefRelationship == Sema::Ref_Compatible ||
4841 (Kind.isCStyleOrFunctionalCast() &&
4842 RefRelationship == Sema::Ref_Related))) {
4843 // - is an lvalue (but is not a bit-field), and "cv1 T1" is
4844 // reference-compatible with "cv2 T2," or
4845 if (RefConv & (Sema::ReferenceConversions::DerivedToBase |
4846 Sema::ReferenceConversions::ObjC)) {
4847 // If we're converting the pointee, add any qualifiers first;
4848 // these qualifiers must all be top-level, so just convert to "cv1 T2".
4849 if (RefConv & (Sema::ReferenceConversions::Qualification))
4850 Sequence.AddQualificationConversionStep(
4851 S.Context.getQualifiedType(T2, T1Quals),
4852 Initializer->getValueKind());
4853 if (RefConv & Sema::ReferenceConversions::DerivedToBase)
4854 Sequence.AddDerivedToBaseCastStep(cv1T1, VK_LValue);
4855 else
4856 Sequence.AddObjCObjectConversionStep(cv1T1);
4857 } else if (RefConv & Sema::ReferenceConversions::Qualification) {
4858 // Perform a (possibly multi-level) qualification conversion.
4859 Sequence.AddQualificationConversionStep(cv1T1,
4860 Initializer->getValueKind());
4861 } else if (RefConv & Sema::ReferenceConversions::Function) {
4862 Sequence.AddFunctionReferenceConversionStep(cv1T1);
4863 }
4864
4865 // We only create a temporary here when binding a reference to a
4866 // bit-field or vector element. Those cases are't supposed to be
4867 // handled by this bullet, but the outcome is the same either way.
4868 Sequence.AddReferenceBindingStep(cv1T1, false);
4869 return;
4870 }
4871
4872 // - has a class type (i.e., T2 is a class type), where T1 is not
4873 // reference-related to T2, and can be implicitly converted to an
4874 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible
4875 // with "cv3 T3" (this conversion is selected by enumerating the
4876 // applicable conversion functions (13.3.1.6) and choosing the best
4877 // one through overload resolution (13.3)),
4878 // If we have an rvalue ref to function type here, the rhs must be
4879 // an rvalue. DR1287 removed the "implicitly" here.
4880 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() &&
4881 (isLValueRef || InitCategory.isRValue())) {
4882 if (S.getLangOpts().CPlusPlus) {
4883 // Try conversion functions only for C++.
4884 ConvOvlResult = TryRefInitWithConversionFunction(
4885 S, Entity, Kind, Initializer, /*AllowRValues*/ isRValueRef,
4886 /*IsLValueRef*/ isLValueRef, Sequence);
4887 if (ConvOvlResult == OR_Success)
4888 return;
4889 if (ConvOvlResult != OR_No_Viable_Function)
4890 Sequence.SetOverloadFailure(
4891 InitializationSequence::FK_ReferenceInitOverloadFailed,
4892 ConvOvlResult);
4893 } else {
4894 ConvOvlResult = OR_No_Viable_Function;
4895 }
4896 }
4897 }
4898
4899 // - Otherwise, the reference shall be an lvalue reference to a
4900 // non-volatile const type (i.e., cv1 shall be const), or the reference
4901 // shall be an rvalue reference.
4902 // For address spaces, we interpret this to mean that an addr space
4903 // of a reference "cv1 T1" is a superset of addr space of "cv2 T2".
4904 if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile() &&
4905 T1Quals.isAddressSpaceSupersetOf(T2Quals))) {
4906 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
4907 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4908 else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
4909 Sequence.SetOverloadFailure(
4910 InitializationSequence::FK_ReferenceInitOverloadFailed,
4911 ConvOvlResult);
4912 else if (!InitCategory.isLValue())
4913 Sequence.SetFailed(
4914 T1Quals.isAddressSpaceSupersetOf(T2Quals)
4915 ? InitializationSequence::
4916 FK_NonConstLValueReferenceBindingToTemporary
4917 : InitializationSequence::FK_ReferenceInitDropsQualifiers);
4918 else {
4919 InitializationSequence::FailureKind FK;
4920 switch (RefRelationship) {
4921 case Sema::Ref_Compatible:
4922 if (Initializer->refersToBitField())
4923 FK = InitializationSequence::
4924 FK_NonConstLValueReferenceBindingToBitfield;
4925 else if (Initializer->refersToVectorElement())
4926 FK = InitializationSequence::
4927 FK_NonConstLValueReferenceBindingToVectorElement;
4928 else if (Initializer->refersToMatrixElement())
4929 FK = InitializationSequence::
4930 FK_NonConstLValueReferenceBindingToMatrixElement;
4931 else
4932 llvm_unreachable("unexpected kind of compatible initializer")::llvm::llvm_unreachable_internal("unexpected kind of compatible initializer"
, "clang/lib/Sema/SemaInit.cpp", 4932)
;
4933 break;
4934 case Sema::Ref_Related:
4935 FK = InitializationSequence::FK_ReferenceInitDropsQualifiers;
4936 break;
4937 case Sema::Ref_Incompatible:
4938 FK = InitializationSequence::
4939 FK_NonConstLValueReferenceBindingToUnrelated;
4940 break;
4941 }
4942 Sequence.SetFailed(FK);
4943 }
4944 return;
4945 }
4946
4947 // - If the initializer expression
4948 // - is an
4949 // [<=14] xvalue (but not a bit-field), class prvalue, array prvalue, or
4950 // [1z] rvalue (but not a bit-field) or
4951 // function lvalue and "cv1 T1" is reference-compatible with "cv2 T2"
4952 //
4953 // Note: functions are handled above and below rather than here...
4954 if (!T1Function &&
4955 (RefRelationship == Sema::Ref_Compatible ||
4956 (Kind.isCStyleOrFunctionalCast() &&
4957 RefRelationship == Sema::Ref_Related)) &&
4958 ((InitCategory.isXValue() && !isNonReferenceableGLValue(Initializer)) ||
4959 (InitCategory.isPRValue() &&
4960 (S.getLangOpts().CPlusPlus17 || T2->isRecordType() ||
4961 T2->isArrayType())))) {
4962 ExprValueKind ValueKind = InitCategory.isXValue() ? VK_XValue : VK_PRValue;
4963 if (InitCategory.isPRValue() && T2->isRecordType()) {
4964 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the
4965 // compiler the freedom to perform a copy here or bind to the
4966 // object, while C++0x requires that we bind directly to the
4967 // object. Hence, we always bind to the object without making an
4968 // extra copy. However, in C++03 requires that we check for the
4969 // presence of a suitable copy constructor:
4970 //
4971 // The constructor that would be used to make the copy shall
4972 // be callable whether or not the copy is actually done.
4973 if (!S.getLangOpts().CPlusPlus11 && !S.getLangOpts().MicrosoftExt)
4974 Sequence.AddExtraneousCopyToTemporary(cv2T2);
4975 else if (S.getLangOpts().CPlusPlus11)
4976 CheckCXX98CompatAccessibleCopy(S, Entity, Initializer);
4977 }
4978
4979 // C++1z [dcl.init.ref]/5.2.1.2:
4980 // If the converted initializer is a prvalue, its type T4 is adjusted
4981 // to type "cv1 T4" and the temporary materialization conversion is
4982 // applied.
4983 // Postpone address space conversions to after the temporary materialization
4984 // conversion to allow creating temporaries in the alloca address space.
4985 auto T1QualsIgnoreAS = T1Quals;
4986 auto T2QualsIgnoreAS = T2Quals;
4987 if (T1Quals.getAddressSpace() != T2Quals.getAddressSpace()) {
4988 T1QualsIgnoreAS.removeAddressSpace();
4989 T2QualsIgnoreAS.removeAddressSpace();
4990 }
4991 QualType cv1T4 = S.Context.getQualifiedType(cv2T2, T1QualsIgnoreAS);
4992 if (T1QualsIgnoreAS != T2QualsIgnoreAS)
4993 Sequence.AddQualificationConversionStep(cv1T4, ValueKind);
4994 Sequence.AddReferenceBindingStep(cv1T4, ValueKind == VK_PRValue);
4995 ValueKind = isLValueRef ? VK_LValue : VK_XValue;
4996 // Add addr space conversion if required.
4997 if (T1Quals.getAddressSpace() != T2Quals.getAddressSpace()) {
4998 auto T4Quals = cv1T4.getQualifiers();
4999 T4Quals.addAddressSpace(T1Quals.getAddressSpace());
5000 QualType cv1T4WithAS = S.Context.getQualifiedType(T2, T4Quals);
5001 Sequence.AddQualificationConversionStep(cv1T4WithAS, ValueKind);
5002 cv1T4 = cv1T4WithAS;
5003 }
5004
5005 // In any case, the reference is bound to the resulting glvalue (or to
5006 // an appropriate base class subobject).
5007 if (RefConv & Sema::ReferenceConversions::DerivedToBase)
5008 Sequence.AddDerivedToBaseCastStep(cv1T1, ValueKind);
5009 else if (RefConv & Sema::ReferenceConversions::ObjC)
5010 Sequence.AddObjCObjectConversionStep(cv1T1);
5011 else if (RefConv & Sema::ReferenceConversions::Qualification) {
5012 if (!S.Context.hasSameType(cv1T4, cv1T1))
5013 Sequence.AddQualificationConversionStep(cv1T1, ValueKind);
5014 }
5015 return;
5016 }
5017
5018 // - has a class type (i.e., T2 is a class type), where T1 is not
5019 // reference-related to T2, and can be implicitly converted to an
5020 // xvalue, class prvalue, or function lvalue of type "cv3 T3",
5021 // where "cv1 T1" is reference-compatible with "cv3 T3",
5022 //
5023 // DR1287 removes the "implicitly" here.
5024 if (T2->isRecordType()) {
5025 if (RefRelationship == Sema::Ref_Incompatible) {
5026 ConvOvlResult = TryRefInitWithConversionFunction(
5027 S, Entity, Kind, Initializer, /*AllowRValues*/ true,
5028 /*IsLValueRef*/ isLValueRef, Sequence);
5029 if (ConvOvlResult)
5030 Sequence.SetOverloadFailure(
5031 InitializationSequence::FK_ReferenceInitOverloadFailed,
5032 ConvOvlResult);
5033
5034 return;
5035 }
5036
5037 if (RefRelationship == Sema::Ref_Compatible &&
5038 isRValueRef && InitCategory.isLValue()) {
5039 Sequence.SetFailed(
5040 InitializationSequence::FK_RValueReferenceBindingToLValue);
5041 return;
5042 }
5043
5044 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
5045 return;
5046 }
5047
5048 // - Otherwise, a temporary of type "cv1 T1" is created and initialized
5049 // from the initializer expression using the rules for a non-reference
5050 // copy-initialization (8.5). The reference is then bound to the
5051 // temporary. [...]
5052
5053 // Ignore address space of reference type at this point and perform address
5054 // space conversion after the reference binding step.
5055 QualType cv1T1IgnoreAS =
5056 T1Quals.hasAddressSpace()
5057 ? S.Context.getQualifiedType(T1, T1Quals.withoutAddressSpace())
5058 : cv1T1;
5059
5060 InitializedEntity TempEntity =
5061 InitializedEntity::InitializeTemporary(cv1T1IgnoreAS);
5062
5063 // FIXME: Why do we use an implicit conversion here rather than trying
5064 // copy-initialization?
5065 ImplicitConversionSequence ICS
5066 = S.TryImplicitConversion(Initializer, TempEntity.getType(),
5067 /*SuppressUserConversions=*/false,
5068 Sema::AllowedExplicit::None,
5069 /*FIXME:InOverloadResolution=*/false,
5070 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
5071 /*AllowObjCWritebackConversion=*/false);
5072
5073 if (ICS.isBad()) {
5074 // FIXME: Use the conversion function set stored in ICS to turn
5075 // this into an overloading ambiguity diagnostic. However, we need
5076 // to keep that set as an OverloadCandidateSet rather than as some
5077 // other kind of set.
5078 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
5079 Sequence.SetOverloadFailure(
5080 InitializationSequence::FK_ReferenceInitOverloadFailed,
5081 ConvOvlResult);
5082 else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
5083 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
5084 else
5085 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed);
5086 return;
5087 } else {
5088 Sequence.AddConversionSequenceStep(ICS, TempEntity.getType());
5089 }
5090
5091 // [...] If T1 is reference-related to T2, cv1 must be the
5092 // same cv-qualification as, or greater cv-qualification
5093 // than, cv2; otherwise, the program is ill-formed.
5094 unsigned T1CVRQuals = T1Quals.getCVRQualifiers();
5095 unsigned T2CVRQuals = T2Quals.getCVRQualifiers();
5096 if (RefRelationship == Sema::Ref_Related &&
5097 ((T1CVRQuals | T2CVRQuals) != T1CVRQuals ||
5098 !T1Quals.isAddressSpaceSupersetOf(T2Quals))) {
5099 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
5100 return;
5101 }
5102
5103 // [...] If T1 is reference-related to T2 and the reference is an rvalue
5104 // reference, the initializer expression shall not be an lvalue.
5105 if (RefRelationship >= Sema::Ref_Related && !isLValueRef &&
5106 InitCategory.isLValue()) {
5107 Sequence.SetFailed(
5108 InitializationSequence::FK_RValueReferenceBindingToLValue);
5109 return;
5110 }
5111
5112 Sequence.AddReferenceBindingStep(cv1T1IgnoreAS, /*BindingTemporary=*/true);
5113
5114 if (T1Quals.hasAddressSpace()) {
5115 if (!Qualifiers::isAddressSpaceSupersetOf(T1Quals.getAddressSpace(),
5116 LangAS::Default)) {
5117 Sequence.SetFailed(
5118 InitializationSequence::FK_ReferenceAddrspaceMismatchTemporary);
5119 return;
5120 }
5121 Sequence.AddQualificationConversionStep(cv1T1, isLValueRef ? VK_LValue
5122 : VK_XValue);
5123 }
5124}
5125
5126/// Attempt character array initialization from a string literal
5127/// (C++ [dcl.init.string], C99 6.7.8).
5128static void TryStringLiteralInitialization(Sema &S,
5129 const InitializedEntity &Entity,
5130 const InitializationKind &Kind,
5131 Expr *Initializer,
5132 InitializationSequence &Sequence) {
5133 Sequence.AddStringInitStep(Entity.getType());
5134}
5135
5136/// Attempt value initialization (C++ [dcl.init]p7).
5137static void TryValueInitialization(Sema &S,
5138 const InitializedEntity &Entity,
5139 const InitializationKind &Kind,
5140 InitializationSequence &Sequence,
5141 InitListExpr *InitList) {
5142 assert((!InitList || InitList->getNumInits() == 0) &&(static_cast <bool> ((!InitList || InitList->getNumInits
() == 0) && "Shouldn't use value-init for non-empty init lists"
) ? void (0) : __assert_fail ("(!InitList || InitList->getNumInits() == 0) && \"Shouldn't use value-init for non-empty init lists\""
, "clang/lib/Sema/SemaInit.cpp", 5143, __extension__ __PRETTY_FUNCTION__
))
5143 "Shouldn't use value-init for non-empty init lists")(static_cast <bool> ((!InitList || InitList->getNumInits
() == 0) && "Shouldn't use value-init for non-empty init lists"
) ? void (0) : __assert_fail ("(!InitList || InitList->getNumInits() == 0) && \"Shouldn't use value-init for non-empty init lists\""
, "clang/lib/Sema/SemaInit.cpp", 5143, __extension__ __PRETTY_FUNCTION__
))
;
5144
5145 // C++98 [dcl.init]p5, C++11 [dcl.init]p7:
5146 //
5147 // To value-initialize an object of type T means:
5148 QualType T = Entity.getType();
5149
5150 // -- if T is an array type, then each element is value-initialized;
5151 T = S.Context.getBaseElementType(T);
5152
5153 if (const RecordType *RT = T->getAs<RecordType>()) {
5154 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5155 bool NeedZeroInitialization = true;
5156 // C++98:
5157 // -- if T is a class type (clause 9) with a user-declared constructor
5158 // (12.1), then the default constructor for T is called (and the
5159 // initialization is ill-formed if T has no accessible default
5160 // constructor);
5161 // C++11:
5162 // -- if T is a class type (clause 9) with either no default constructor
5163 // (12.1 [class.ctor]) or a default constructor that is user-provided
5164 // or deleted, then the object is default-initialized;
5165 //
5166 // Note that the C++11 rule is the same as the C++98 rule if there are no
5167 // defaulted or deleted constructors, so we just use it unconditionally.
5168 CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl);
5169 if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted())
5170 NeedZeroInitialization = false;
5171
5172 // -- if T is a (possibly cv-qualified) non-union class type without a
5173 // user-provided or deleted default constructor, then the object is
5174 // zero-initialized and, if T has a non-trivial default constructor,
5175 // default-initialized;
5176 // The 'non-union' here was removed by DR1502. The 'non-trivial default
5177 // constructor' part was removed by DR1507.
5178 if (NeedZeroInitialization)
5179 Sequence.AddZeroInitializationStep(Entity.getType());
5180
5181 // C++03:
5182 // -- if T is a non-union class type without a user-declared constructor,
5183 // then every non-static data member and base class component of T is
5184 // value-initialized;
5185 // [...] A program that calls for [...] value-initialization of an
5186 // entity of reference type is ill-formed.
5187 //
5188 // C++11 doesn't need this handling, because value-initialization does not
5189 // occur recursively there, and the implicit default constructor is
5190 // defined as deleted in the problematic cases.
5191 if (!S.getLangOpts().CPlusPlus11 &&
5192 ClassDecl->hasUninitializedReferenceMember()) {
5193 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForReference);
5194 return;
5195 }
5196
5197 // If this is list-value-initialization, pass the empty init list on when
5198 // building the constructor call. This affects the semantics of a few
5199 // things (such as whether an explicit default constructor can be called).
5200 Expr *InitListAsExpr = InitList;
5201 MultiExprArg Args(&InitListAsExpr, InitList ? 1 : 0);
5202 bool InitListSyntax = InitList;
5203
5204 // FIXME: Instead of creating a CXXConstructExpr of array type here,
5205 // wrap a class-typed CXXConstructExpr in an ArrayInitLoopExpr.
5206 return TryConstructorInitialization(
5207 S, Entity, Kind, Args, T, Entity.getType(), Sequence, InitListSyntax);
5208 }
5209 }
5210
5211 Sequence.AddZeroInitializationStep(Entity.getType());
5212}
5213
5214/// Attempt default initialization (C++ [dcl.init]p6).
5215static void TryDefaultInitialization(Sema &S,
5216 const InitializedEntity &Entity,
5217 const InitializationKind &Kind,
5218 InitializationSequence &Sequence) {
5219 assert(Kind.getKind() == InitializationKind::IK_Default)(static_cast <bool> (Kind.getKind() == InitializationKind
::IK_Default) ? void (0) : __assert_fail ("Kind.getKind() == InitializationKind::IK_Default"
, "clang/lib/Sema/SemaInit.cpp", 5219, __extension__ __PRETTY_FUNCTION__
))
;
5220
5221 // C++ [dcl.init]p6:
5222 // To default-initialize an object of type T means:
5223 // - if T is an array type, each element is default-initialized;
5224 QualType DestType = S.Context.getBaseElementType(Entity.getType());
5225
5226 // - if T is a (possibly cv-qualified) class type (Clause 9), the default
5227 // constructor for T is called (and the initialization is ill-formed if
5228 // T has no accessible default constructor);
5229 if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) {
5230 TryConstructorInitialization(S, Entity, Kind, None, DestType,
5231 Entity.getType(), Sequence);
5232 return;
5233 }
5234
5235 // - otherwise, no initialization is performed.
5236
5237 // If a program calls for the default initialization of an object of
5238 // a const-qualified type T, T shall be a class type with a user-provided
5239 // default constructor.
5240 if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) {
5241 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
5242 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
5243 return;
5244 }
5245
5246 // If the destination type has a lifetime property, zero-initialize it.
5247 if (DestType.getQualifiers().hasObjCLifetime()) {
5248 Sequence.AddZeroInitializationStep(Entity.getType());
5249 return;
5250 }
5251}
5252
5253/// Attempt a user-defined conversion between two types (C++ [dcl.init]),
5254/// which enumerates all conversion functions and performs overload resolution
5255/// to select the best.
5256static void TryUserDefinedConversion(Sema &S,
5257 QualType DestType,
5258 const InitializationKind &Kind,
5259 Expr *Initializer,
5260 InitializationSequence &Sequence,
5261 bool TopLevelOfInitList) {
5262 assert(!DestType->isReferenceType() && "References are handled elsewhere")(static_cast <bool> (!DestType->isReferenceType() &&
"References are handled elsewhere") ? void (0) : __assert_fail
("!DestType->isReferenceType() && \"References are handled elsewhere\""
, "clang/lib/Sema/SemaInit.cpp", 5262, __extension__ __PRETTY_FUNCTION__
))
;
5263 QualType SourceType = Initializer->getType();
5264 assert((DestType->isRecordType() || SourceType->isRecordType()) &&(static_cast <bool> ((DestType->isRecordType() || SourceType
->isRecordType()) && "Must have a class type to perform a user-defined conversion"
) ? void (0) : __assert_fail ("(DestType->isRecordType() || SourceType->isRecordType()) && \"Must have a class type to perform a user-defined conversion\""
, "clang/lib/Sema/SemaInit.cpp", 5265, __extension__ __PRETTY_FUNCTION__
))
5265 "Must have a class type to perform a user-defined conversion")(static_cast <bool> ((DestType->isRecordType() || SourceType
->isRecordType()) && "Must have a class type to perform a user-defined conversion"
) ? void (0) : __assert_fail ("(DestType->isRecordType() || SourceType->isRecordType()) && \"Must have a class type to perform a user-defined conversion\""
, "clang/lib/Sema/SemaInit.cpp", 5265, __extension__ __PRETTY_FUNCTION__
))
;
5266
5267 // Build the candidate set directly in the initialization sequence
5268 // structure, so that it will persist if we fail.
5269 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
5270 CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
5271 CandidateSet.setDestAS(DestType.getQualifiers().getAddressSpace());
5272
5273 // Determine whether we are allowed to call explicit constructors or
5274 // explicit conversion operators.
5275 bool AllowExplicit = Kind.AllowExplicit();
5276
5277 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) {
5278 // The type we're converting to is a class type. Enumerate its constructors
5279 // to see if there is a suitable conversion.
5280 CXXRecordDecl *DestRecordDecl
5281 = cast<CXXRecordDecl>(DestRecordType->getDecl());
5282
5283 // Try to complete the type we're converting to.
5284 if (S.isCompleteType(Kind.getLocation(), DestType)) {
5285 for (NamedDecl *D : S.LookupConstructors(DestRecordDecl)) {
5286 auto Info = getConstructorInfo(D);
5287 if (!Info.Constructor)
5288 continue;
5289
5290 if (!Info.Constructor->isInvalidDecl() &&
5291 Info.Constructor->isConvertingConstructor(/*AllowExplicit*/true)) {
5292 if (Info.ConstructorTmpl)
5293 S.AddTemplateOverloadCandidate(
5294 Info.ConstructorTmpl, Info.FoundDecl,
5295 /*ExplicitArgs*/ nullptr, Initializer, CandidateSet,
5296 /*SuppressUserConversions=*/true,
5297 /*PartialOverloading*/ false, AllowExplicit);
5298 else
5299 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
5300 Initializer, CandidateSet,
5301 /*SuppressUserConversions=*/true,
5302 /*PartialOverloading*/ false, AllowExplicit);
5303 }
5304 }
5305 }
5306 }
5307
5308 SourceLocation DeclLoc = Initializer->getBeginLoc();
5309
5310 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) {
5311 // The type we're converting from is a class type, enumerate its conversion
5312 // functions.
5313
5314 // We can only enumerate the conversion functions for a complete type; if
5315 // the type isn't complete, simply skip this step.
5316 if (S.isCompleteType(DeclLoc, SourceType)) {
5317 CXXRecordDecl *SourceRecordDecl
5318 = cast<CXXRecordDecl>(SourceRecordType->getDecl());
5319
5320 const auto &Conversions =
5321 SourceRecordDecl->getVisibleConversionFunctions();
5322 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
5323 NamedDecl *D = *I;
5324 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
5325 if (isa<UsingShadowDecl>(D))
5326 D = cast<UsingShadowDecl>(D)->getTargetDecl();
5327
5328 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
5329 CXXConversionDecl *Conv;
5330 if (ConvTemplate)
5331 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
5332 else
5333 Conv = cast<CXXConversionDecl>(D);
5334
5335 if (ConvTemplate)
5336 S.AddTemplateConversionCandidate(
5337 ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
5338 CandidateSet, AllowExplicit, AllowExplicit);
5339 else
5340 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Initializer,
5341 DestType, CandidateSet, AllowExplicit,
5342 AllowExplicit);
5343 }
5344 }
5345 }
5346
5347 // Perform overload resolution. If it fails, return the failed result.
5348 OverloadCandidateSet::iterator Best;
5349 if (OverloadingResult Result
5350 = CandidateSet.BestViableFunction(S, DeclLoc, Best)) {
5351 Sequence.SetOverloadFailure(
5352 InitializationSequence::FK_UserConversionOverloadFailed, Result);
5353
5354 // [class.copy.elision]p3:
5355 // In some copy-initialization contexts, a two-stage overload resolution
5356 // is performed.
5357 // If the first overload resolution selects a deleted function, we also
5358 // need the initialization sequence to decide whether to perform the second
5359 // overload resolution.
5360 if (!(Result == OR_Deleted &&
5361 Kind.getKind() == InitializationKind::IK_Copy))
5362 return;
5363 }
5364
5365 FunctionDecl *Function = Best->Function;
5366 Function->setReferenced();
5367 bool HadMultipleCandidates = (CandidateSet.size() > 1);
5368
5369 if (isa<CXXConstructorDecl>(Function)) {
5370 // Add the user-defined conversion step. Any cv-qualification conversion is
5371 // subsumed by the initialization. Per DR5, the created temporary is of the
5372 // cv-unqualified type of the destination.
5373 Sequence.AddUserConversionStep(Function, Best->FoundDecl,
5374 DestType.getUnqualifiedType(),
5375 HadMultipleCandidates);
5376
5377 // C++14 and before:
5378 // - if the function is a constructor, the call initializes a temporary
5379 // of the cv-unqualified version of the destination type. The [...]
5380 // temporary [...] is then used to direct-initialize, according to the
5381 // rules above, the object that is the destination of the
5382 // copy-initialization.
5383 // Note that this just performs a simple object copy from the temporary.
5384 //
5385 // C++17:
5386 // - if the function is a constructor, the call is a prvalue of the
5387 // cv-unqualified version of the destination type whose return object
5388 // is initialized by the constructor. The call is used to
5389 // direct-initialize, according to the rules above, the object that
5390 // is the destination of the copy-initialization.
5391 // Therefore we need to do nothing further.
5392 //
5393 // FIXME: Mark this copy as extraneous.
5394 if (!S.getLangOpts().CPlusPlus17)
5395 Sequence.AddFinalCopy(DestType);
5396 else if (DestType.hasQualifiers())
5397 Sequence.AddQualificationConversionStep(DestType, VK_PRValue);
5398 return;
5399 }
5400
5401 // Add the user-defined conversion step that calls the conversion function.
5402 QualType ConvType = Function->getCallResultType();
5403 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType,
5404 HadMultipleCandidates);
5405
5406 if (ConvType->getAs<RecordType>()) {
5407 // The call is used to direct-initialize [...] the object that is the
5408 // destination of the copy-initialization.
5409 //
5410 // In C++17, this does not call a constructor if we enter /17.6.1:
5411 // - If the initializer expression is a prvalue and the cv-unqualified
5412 // version of the source type is the same as the class of the
5413 // destination [... do not make an extra copy]
5414 //
5415 // FIXME: Mark this copy as extraneous.
5416 if (!S.getLangOpts().CPlusPlus17 ||
5417 Function->getReturnType()->isReferenceType() ||
5418 !S.Context.hasSameUnqualifiedType(ConvType, DestType))
5419 Sequence.AddFinalCopy(DestType);
5420 else if (!S.Context.hasSameType(ConvType, DestType))
5421 Sequence.AddQualificationConversionStep(DestType, VK_PRValue);
5422 return;
5423 }
5424
5425 // If the conversion following the call to the conversion function
5426 // is interesting, add it as a separate step.
5427 if (Best->FinalConversion.First || Best->FinalConversion.Second ||
5428 Best->FinalConversion.Third) {
5429 ImplicitConversionSequence ICS;
5430 ICS.setStandard();
5431 ICS.Standard = Best->FinalConversion;
5432 Sequence.AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
5433 }
5434}
5435
5436/// An egregious hack for compatibility with libstdc++-4.2: in <tr1/hashtable>,
5437/// a function with a pointer return type contains a 'return false;' statement.
5438/// In C++11, 'false' is not a null pointer, so this breaks the build of any
5439/// code using that header.
5440///
5441/// Work around this by treating 'return false;' as zero-initializing the result
5442/// if it's used in a pointer-returning function in a system header.
5443static bool isLibstdcxxPointerReturnFalseHack(Sema &S,
5444 const InitializedEntity &Entity,
5445 const Expr *Init) {
5446 return S.getLangOpts().CPlusPlus11 &&
5447 Entity.getKind() == InitializedEntity::EK_Result &&
5448 Entity.getType()->isPointerType() &&
5449 isa<CXXBoolLiteralExpr>(Init) &&
5450 !cast<CXXBoolLiteralExpr>(Init)->getValue() &&
5451 S.getSourceManager().isInSystemHeader(Init->getExprLoc());
5452}
5453
5454/// The non-zero enum values here are indexes into diagnostic alternatives.
5455enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar };
5456
5457/// Determines whether this expression is an acceptable ICR source.
5458static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e,
5459 bool isAddressOf, bool &isWeakAccess) {
5460 // Skip parens.
5461 e = e->IgnoreParens();
5462
5463 // Skip address-of nodes.
5464 if (UnaryOperator *op = dyn_cast<UnaryOperator>(e)) {
5465 if (op->getOpcode() == UO_AddrOf)
5466 return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true,
5467 isWeakAccess);
5468
5469 // Skip certain casts.
5470 } else if (CastExpr *ce = dyn_cast<CastExpr>(e)) {
5471 switch (ce->getCastKind()) {
5472 case CK_Dependent:
5473 case CK_BitCast:
5474 case CK_LValueBitCast:
5475 case CK_NoOp:
5476 return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf, isWeakAccess);
5477
5478 case CK_ArrayToPointerDecay:
5479 return IIK_nonscalar;
5480
5481 case CK_NullToPointer:
5482 return IIK_okay;
5483
5484 default:
5485 break;
5486 }
5487
5488 // If we have a declaration reference, it had better be a local variable.
5489 } else if (isa<DeclRefExpr>(e)) {
5490 // set isWeakAccess to true, to mean that there will be an implicit
5491 // load which requires a cleanup.
5492 if (e->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
5493 isWeakAccess = true;
5494
5495 if (!isAddressOf) return IIK_nonlocal;
5496
5497 VarDecl *var = dyn_cast<VarDecl>(cast<DeclRefExpr>(e)->getDecl());
5498 if (!var) return IIK_nonlocal;
5499
5500 return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal);
5501
5502 // If we have a conditional operator, check both sides.
5503 } else if (ConditionalOperator *cond = dyn_cast<ConditionalOperator>(e)) {
5504 if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf,
5505 isWeakAccess))
5506 return iik;
5507
5508 return isInvalidICRSource(C, cond->getRHS(), isAddressOf, isWeakAccess);
5509
5510 // These are never scalar.
5511 } else if (isa<ArraySubscriptExpr>(e)) {
5512 return IIK_nonscalar;
5513
5514 // Otherwise, it needs to be a null pointer constant.
5515 } else {
5516 return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull)
5517 ? IIK_okay : IIK_nonlocal);
5518 }
5519
5520 return IIK_nonlocal;
5521}
5522
5523/// Check whether the given expression is a valid operand for an
5524/// indirect copy/restore.
5525static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) {
5526 assert(src->isPRValue())(static_cast <bool> (src->isPRValue()) ? void (0) : __assert_fail
("src->isPRValue()", "clang/lib/Sema/SemaInit.cpp", 5526,
__extension__ __PRETTY_FUNCTION__))
;
5527 bool isWeakAccess = false;
5528 InvalidICRKind iik = isInvalidICRSource(S.Context, src, false, isWeakAccess);
5529 // If isWeakAccess to true, there will be an implicit
5530 // load which requires a cleanup.
5531 if (S.getLangOpts().ObjCAutoRefCount && isWeakAccess)
5532 S.Cleanup.setExprNeedsCleanups(true);
5533
5534 if (iik == IIK_okay) return;
5535
5536 S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback)
5537 << ((unsigned) iik - 1) // shift index into diagnostic explanations
5538 << src->getSourceRange();
5539}
5540
5541/// Determine whether we have compatible array types for the
5542/// purposes of GNU by-copy array initialization.
5543static bool hasCompatibleArrayTypes(ASTContext &Context, const ArrayType *Dest,
5544 const ArrayType *Source) {
5545 // If the source and destination array types are equivalent, we're
5546 // done.
5547 if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0)))
5548 return true;
5549
5550 // Make sure that the element types are the same.
5551 if (!Context.hasSameType(Dest->getElementType(), Source->getElementType()))
5552 return false;
5553
5554 // The only mismatch we allow is when the destination is an
5555 // incomplete array type and the source is a constant array type.
5556 return Source->isConstantArrayType() && Dest->isIncompleteArrayType();
5557}
5558
5559static bool tryObjCWritebackConversion(Sema &S,
5560 InitializationSequence &Sequence,
5561 const InitializedEntity &Entity,
5562 Expr *Initializer) {
5563 bool ArrayDecay = false;
5564 QualType ArgType = Initializer->getType();
5565 QualType ArgPointee;
5566 if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) {
5567 ArrayDecay = true;
5568 ArgPointee = ArgArrayType->getElementType();
5569 ArgType = S.Context.getPointerType(ArgPointee);
5570 }
5571
5572 // Handle write-back conversion.
5573 QualType ConvertedArgType;
5574 if (!S.isObjCWritebackConversion(ArgType, Entity.getType(),
5575 ConvertedArgType))
5576 return false;
5577
5578 // We should copy unless we're passing to an argument explicitly
5579 // marked 'out'.
5580 bool ShouldCopy = true;
5581 if (ParmVarDecl *param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
5582 ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
5583
5584 // Do we need an lvalue conversion?
5585 if (ArrayDecay || Initializer->isGLValue()) {
5586 ImplicitConversionSequence ICS;
5587 ICS.setStandard();
5588 ICS.Standard.setAsIdentityConversion();
5589
5590 QualType ResultType;
5591 if (ArrayDecay) {
5592 ICS.Standard.First = ICK_Array_To_Pointer;
5593 ResultType = S.Context.getPointerType(ArgPointee);
5594 } else {
5595 ICS.Standard.First = ICK_Lvalue_To_Rvalue;
5596 ResultType = Initializer->getType().getNonLValueExprType(S.Context);
5597 }
5598
5599 Sequence.AddConversionSequenceStep(ICS, ResultType);
5600 }
5601
5602 Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy);
5603 return true;
5604}
5605
5606static bool TryOCLSamplerInitialization(Sema &S,
5607 InitializationSequence &Sequence,
5608 QualType DestType,
5609 Expr *Initializer) {
5610 if (!S.getLangOpts().OpenCL || !DestType->isSamplerT() ||
5611 (!Initializer->isIntegerConstantExpr(S.Context) &&
5612 !Initializer->getType()->isSamplerT()))
5613 return false;
5614
5615 Sequence.AddOCLSamplerInitStep(DestType);
5616 return true;
5617}
5618
5619static bool IsZeroInitializer(Expr *Initializer, Sema &S) {
5620 return Initializer->isIntegerConstantExpr(S.getASTContext()) &&
5621 (Initializer->EvaluateKnownConstInt(S.getASTContext()) == 0);
5622}
5623
5624static bool TryOCLZeroOpaqueTypeInitialization(Sema &S,
5625 InitializationSequence &Sequence,
5626 QualType DestType,
5627 Expr *Initializer) {
5628 if (!S.getLangOpts().OpenCL)
5629 return false;
5630
5631 //
5632 // OpenCL 1.2 spec, s6.12.10
5633 //
5634 // The event argument can also be used to associate the
5635 // async_work_group_copy with a previous async copy allowing
5636 // an event to be shared by multiple async copies; otherwise
5637 // event should be zero.
5638 //
5639 if (DestType->isEventT() || DestType->isQueueT()) {
5640 if (!IsZeroInitializer(Initializer, S))
5641 return false;
5642
5643 Sequence.AddOCLZeroOpaqueTypeStep(DestType);
5644 return true;
5645 }
5646
5647 // We should allow zero initialization for all types defined in the
5648 // cl_intel_device_side_avc_motion_estimation extension, except
5649 // intel_sub_group_avc_mce_payload_t and intel_sub_group_avc_mce_result_t.
5650 if (S.getOpenCLOptions().isAvailableOption(
5651 "cl_intel_device_side_avc_motion_estimation", S.getLangOpts()) &&
5652 DestType->isOCLIntelSubgroupAVCType()) {
5653 if (DestType->isOCLIntelSubgroupAVCMcePayloadType() ||
5654 DestType->isOCLIntelSubgroupAVCMceResultType())
5655 return false;
5656 if (!IsZeroInitializer(Initializer, S))
5657 return false;
5658
5659 Sequence.AddOCLZeroOpaqueTypeStep(DestType);
5660 return true;
5661 }
5662
5663 return false;
5664}
5665
5666InitializationSequence::InitializationSequence(
5667 Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind,
5668 MultiExprArg Args, bool TopLevelOfInitList, bool TreatUnavailableAsInvalid)
5669 : FailedOverloadResult(OR_Success),
5670 FailedCandidateSet(Kind.getLocation(), OverloadCandidateSet::CSK_Normal) {
5671 InitializeFrom(S, Entity, Kind, Args, TopLevelOfInitList,
5672 TreatUnavailableAsInvalid);
5673}
5674
5675/// Tries to get a FunctionDecl out of `E`. If it succeeds and we can take the
5676/// address of that function, this returns true. Otherwise, it returns false.
5677static bool isExprAnUnaddressableFunction(Sema &S, const Expr *E) {
5678 auto *DRE = dyn_cast<DeclRefExpr>(E);
5679 if (!DRE || !isa<FunctionDecl>(DRE->getDecl()))
5680 return false;
5681
5682 return !S.checkAddressOfFunctionIsAvailable(
5683 cast<FunctionDecl>(DRE->getDecl()));
5684}
5685
5686/// Determine whether we can perform an elementwise array copy for this kind
5687/// of entity.
5688static bool canPerformArrayCopy(const InitializedEntity &Entity) {
5689 switch (Entity.getKind()) {
5690 case InitializedEntity::EK_LambdaCapture:
5691 // C++ [expr.prim.lambda]p24:
5692 // For array members, the array elements are direct-initialized in
5693 // increasing subscript order.
5694 return true;
5695
5696 case InitializedEntity::EK_Variable:
5697 // C++ [dcl.decomp]p1:
5698 // [...] each element is copy-initialized or direct-initialized from the
5699 // corresponding element of the assignment-expression [...]
5700 return isa<DecompositionDecl>(Entity.getDecl());
5701
5702 case InitializedEntity::EK_Member:
5703 // C++ [class.copy.ctor]p14:
5704 // - if the member is an array, each element is direct-initialized with
5705 // the corresponding subobject of x
5706 return Entity.isImplicitMemberInitializer();
5707
5708 case InitializedEntity::EK_ArrayElement:
5709 // All the above cases are intended to apply recursively, even though none
5710 // of them actually say that.
5711 if (auto *E = Entity.getParent())
5712 return canPerformArrayCopy(*E);
5713 break;
5714
5715 default:
5716 break;
5717 }
5718
5719 return false;
5720}
5721
5722void InitializationSequence::InitializeFrom(Sema &S,
5723 const InitializedEntity &Entity,
5724 const InitializationKind &Kind,
5725 MultiExprArg Args,
5726 bool TopLevelOfInitList,
5727 bool TreatUnavailableAsInvalid) {
5728 ASTContext &Context = S.Context;
5729
5730 // Eliminate non-overload placeholder types in the arguments. We
5731 // need to do this before checking whether types are dependent
5732 // because lowering a pseudo-object expression might well give us
5733 // something of dependent type.
5734 for (unsigned I = 0, E = Args.size(); I != E; ++I)
5735 if (Args[I]->getType()->isNonOverloadPlaceholderType()) {
5736 // FIXME: should we be doing this here?
5737 ExprResult result = S.CheckPlaceholderExpr(Args[I]);
5738 if (result.isInvalid()) {
5739 SetFailed(FK_PlaceholderType);
5740 return;
5741 }
5742 Args[I] = result.get();
5743 }
5744
5745 // C++0x [dcl.init]p16:
5746 // The semantics of initializers are as follows. The destination type is
5747 // the type of the object or reference being initialized and the source
5748 // type is the type of the initializer expression. The source type is not
5749 // defined when the initializer is a braced-init-list or when it is a
5750 // parenthesized list of expressions.
5751 QualType DestType = Entity.getType();
5752
5753 if (DestType->isDependentType() ||
5754 Expr::hasAnyTypeDependentArguments(Args)) {
5755 SequenceKind = DependentSequence;
5756 return;
5757 }
5758
5759 // Almost everything is a normal sequence.
5760 setSequenceKind(NormalSequence);
5761
5762 QualType SourceType;
5763 Expr *Initializer = nullptr;
5764 if (Args.size() == 1) {
5765 Initializer = Args[0];
5766 if (S.getLangOpts().ObjC) {
5767 if (S.CheckObjCBridgeRelatedConversions(Initializer->getBeginLoc(),
5768 DestType, Initializer->getType(),
5769 Initializer) ||
5770 S.CheckConversionToObjCLiteral(DestType, Initializer))
5771 Args[0] = Initializer;
5772 }
5773 if (!isa<InitListExpr>(Initializer))
5774 SourceType = Initializer->getType();
5775 }
5776
5777 // - If the initializer is a (non-parenthesized) braced-init-list, the
5778 // object is list-initialized (8.5.4).
5779 if (Kind.getKind() != InitializationKind::IK_Direct) {
5780 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) {
5781 TryListInitialization(S, Entity, Kind, InitList, *this,
5782 TreatUnavailableAsInvalid);
5783 return;
5784 }
5785 }
5786
5787 // - If the destination type is a reference type, see 8.5.3.
5788 if (DestType->isReferenceType()) {
5789 // C++0x [dcl.init.ref]p1:
5790 // A variable declared to be a T& or T&&, that is, "reference to type T"
5791 // (8.3.2), shall be initialized by an object, or function, of type T or
5792 // by an object that can be converted into a T.
5793 // (Therefore, multiple arguments are not permitted.)
5794 if (Args.size() != 1)
5795 SetFailed(FK_TooManyInitsForReference);
5796 // C++17 [dcl.init.ref]p5:
5797 // A reference [...] is initialized by an expression [...] as follows:
5798 // If the initializer is not an expression, presumably we should reject,
5799 // but the standard fails to actually say so.
5800 else if (isa<InitListExpr>(Args[0]))
5801 SetFailed(FK_ParenthesizedListInitForReference);
5802 else
5803 TryReferenceInitialization(S, Entity, Kind, Args[0], *this);
5804 return;
5805 }
5806
5807 // - If the initializer is (), the object is value-initialized.
5808 if (Kind.getKind() == InitializationKind::IK_Value ||
5809 (Kind.getKind() == InitializationKind::IK_Direct && Args.empty())) {
5810 TryValueInitialization(S, Entity, Kind, *this);
5811 return;
5812 }
5813
5814 // Handle default initialization.
5815 if (Kind.getKind() == InitializationKind::IK_Default) {
5816 TryDefaultInitialization(S, Entity, Kind, *this);
5817 return;
5818 }
5819
5820 // - If the destination type is an array of characters, an array of
5821 // char16_t, an array of char32_t, or an array of wchar_t, and the
5822 // initializer is a string literal, see 8.5.2.
5823 // - Otherwise, if the destination type is an array, the program is
5824 // ill-formed.
5825 if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) {
5826 if (Initializer && isa<VariableArrayType>(DestAT)) {
5827 SetFailed(FK_VariableLengthArrayHasInitializer);
5828 return;
5829 }
5830
5831 if (Initializer) {
5832 switch (IsStringInit(Initializer, DestAT, Context)) {
5833 case SIF_None:
5834 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this);
5835 return;
5836 case SIF_NarrowStringIntoWideChar:
5837 SetFailed(FK_NarrowStringIntoWideCharArray);
5838 return;
5839 case SIF_WideStringIntoChar:
5840 SetFailed(FK_WideStringIntoCharArray);
5841 return;
5842 case SIF_IncompatWideStringIntoWideChar:
5843 SetFailed(FK_IncompatWideStringIntoWideChar);
5844 return;
5845 case SIF_PlainStringIntoUTF8Char:
5846 SetFailed(FK_PlainStringIntoUTF8Char);
5847 return;
5848 case SIF_UTF8StringIntoPlainChar:
5849 SetFailed(FK_UTF8StringIntoPlainChar);
5850 return;
5851 case SIF_Other:
5852 break;
5853 }
5854 }
5855
5856 // Some kinds of initialization permit an array to be initialized from
5857 // another array of the same type, and perform elementwise initialization.
5858 if (Initializer && isa<ConstantArrayType>(DestAT) &&
5859 S.Context.hasSameUnqualifiedType(Initializer->getType(),
5860 Entity.getType()) &&
5861 canPerformArrayCopy(Entity)) {
5862 // If source is a prvalue, use it directly.
5863 if (Initializer->isPRValue()) {
5864 AddArrayInitStep(DestType, /*IsGNUExtension*/false);
5865 return;
5866 }
5867
5868 // Emit element-at-a-time copy loop.
5869 InitializedEntity Element =
5870 InitializedEntity::InitializeElement(S.Context, 0, Entity);
5871 QualType InitEltT =
5872 Context.getAsArrayType(Initializer->getType())->getElementType();
5873 OpaqueValueExpr OVE(Initializer->getExprLoc(), InitEltT,
5874 Initializer->getValueKind(),
5875 Initializer->getObjectKind());
5876 Expr *OVEAsExpr = &OVE;
5877 InitializeFrom(S, Element, Kind, OVEAsExpr, TopLevelOfInitList,
5878 TreatUnavailableAsInvalid);
5879 if (!Failed())
5880 AddArrayInitLoopStep(Entity.getType(), InitEltT);
5881 return;
5882 }
5883
5884 // Note: as an GNU C extension, we allow initialization of an
5885 // array from a compound literal that creates an array of the same
5886 // type, so long as the initializer has no side effects.
5887 if (!S.getLangOpts().CPlusPlus && Initializer &&
5888 isa<CompoundLiteralExpr>(Initializer->IgnoreParens()) &&
5889 Initializer->getType()->isArrayType()) {
5890 const ArrayType *SourceAT
5891 = Context.getAsArrayType(Initializer->getType());
5892 if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT))
5893 SetFailed(FK_ArrayTypeMismatch);
5894 else if (Initializer->HasSideEffects(S.Context))
5895 SetFailed(FK_NonConstantArrayInit);
5896 else {
5897 AddArrayInitStep(DestType, /*IsGNUExtension*/true);
5898 }
5899 }
5900 // Note: as a GNU C++ extension, we allow list-initialization of a
5901 // class member of array type from a parenthesized initializer list.
5902 else if (S.getLangOpts().CPlusPlus &&
5903 Entity.getKind() == InitializedEntity::EK_Member &&
5904 Initializer && isa<InitListExpr>(Initializer)) {
5905 TryListInitialization(S, Entity, Kind, cast<InitListExpr>(Initializer),
5906 *this, TreatUnavailableAsInvalid);
5907 AddParenthesizedArrayInitStep(DestType);
5908 } else if (DestAT->getElementType()->isCharType())
5909 SetFailed(FK_ArrayNeedsInitListOrStringLiteral);
5910 else if (IsWideCharCompatible(DestAT->getElementType(), Context))
5911 SetFailed(FK_ArrayNeedsInitListOrWideStringLiteral);
5912 else
5913 SetFailed(FK_ArrayNeedsInitList);
5914
5915 return;
5916 }
5917
5918 // Determine whether we should consider writeback conversions for
5919 // Objective-C ARC.
5920 bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount &&
5921 Entity.isParameterKind();
5922
5923 if (TryOCLSamplerInitialization(S, *this, DestType, Initializer))
5924 return;
5925
5926 // We're at the end of the line for C: it's either a write-back conversion
5927 // or it's a C assignment. There's no need to check anything else.
5928 if (!S.getLangOpts().CPlusPlus) {
5929 // If allowed, check whether this is an Objective-C writeback conversion.
5930 if (allowObjCWritebackConversion &&
5931 tryObjCWritebackConversion(S, *this, Entity, Initializer)) {
5932 return;
5933 }
5934
5935 if (TryOCLZeroOpaqueTypeInitialization(S, *this, DestType, Initializer))
5936 return;
5937
5938 // Handle initialization in C
5939 AddCAssignmentStep(DestType);
5940 MaybeProduceObjCObject(S, *this, Entity);
5941 return;
5942 }
5943
5944 assert(S.getLangOpts().CPlusPlus)(static_cast <bool> (S.getLangOpts().CPlusPlus) ? void (
0) : __assert_fail ("S.getLangOpts().CPlusPlus", "clang/lib/Sema/SemaInit.cpp"
, 5944, __extension__ __PRETTY_FUNCTION__))
;
5945
5946 // - If the destination type is a (possibly cv-qualified) class type:
5947 if (DestType->isRecordType()) {
5948 // - If the initialization is direct-initialization, or if it is
5949 // copy-initialization where the cv-unqualified version of the
5950 // source type is the same class as, or a derived class of, the
5951 // class of the destination, constructors are considered. [...]
5952 if (Kind.getKind() == InitializationKind::IK_Direct ||
5953 (Kind.getKind() == InitializationKind::IK_Copy &&
5954 (Context.hasSameUnqualifiedType(SourceType, DestType) ||
5955 S.IsDerivedFrom(Initializer->getBeginLoc(), SourceType, DestType))))
5956 TryConstructorInitialization(S, Entity, Kind, Args,
5957 DestType, DestType, *this);
5958 // - Otherwise (i.e., for the remaining copy-initialization cases),
5959 // user-defined conversion sequences that can convert from the source
5960 // type to the destination type or (when a conversion function is
5961 // used) to a derived class thereof are enumerated as described in
5962 // 13.3.1.4, and the best one is chosen through overload resolution
5963 // (13.3).
5964 else
5965 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
5966 TopLevelOfInitList);
5967 return;
5968 }
5969
5970 assert(Args.size() >= 1 && "Zero-argument case handled above")(static_cast <bool> (Args.size() >= 1 && "Zero-argument case handled above"
) ? void (0) : __assert_fail ("Args.size() >= 1 && \"Zero-argument case handled above\""
, "clang/lib/Sema/SemaInit.cpp", 5970, __extension__ __PRETTY_FUNCTION__
))
;
5971
5972 // For HLSL ext vector types we allow list initialization behavior for C++
5973 // constructor syntax. This is accomplished by converting initialization
5974 // arguments an InitListExpr late.