Bug Summary

File:clang/lib/Sema/SemaInit.cpp
Warning:line 7002, column 16
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 -disable-llvm-verifier -discard-value-names -main-file-name SemaInit.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -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 -fhalf-no-semantic-interposition -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-13/lib/clang/13.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema -I /build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/include -I /build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/build-llvm/include -I /build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-13/lib/clang/13.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2021-02-23-121308-24221-1 -x c++ /build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp

/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/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/SmallString.h"
28#include "llvm/Support/ErrorHandling.h"
29#include "llvm/Support/raw_ostream.h"
30
31using namespace clang;
32
33//===----------------------------------------------------------------------===//
34// Sema Initialization Checking
35//===----------------------------------------------------------------------===//
36
37/// Check whether T is compatible with a wide character type (wchar_t,
38/// char16_t or char32_t).
39static bool IsWideCharCompatible(QualType T, ASTContext &Context) {
40 if (Context.typesAreCompatible(Context.getWideCharType(), T))
41 return true;
42 if (Context.getLangOpts().CPlusPlus || Context.getLangOpts().C11) {
43 return Context.typesAreCompatible(Context.Char16Ty, T) ||
44 Context.typesAreCompatible(Context.Char32Ty, T);
45 }
46 return false;
47}
48
49enum StringInitFailureKind {
50 SIF_None,
51 SIF_NarrowStringIntoWideChar,
52 SIF_WideStringIntoChar,
53 SIF_IncompatWideStringIntoWideChar,
54 SIF_UTF8StringIntoPlainChar,
55 SIF_PlainStringIntoUTF8Char,
56 SIF_Other
57};
58
59/// Check whether the array of type AT can be initialized by the Init
60/// expression by means of string initialization. Returns SIF_None if so,
61/// otherwise returns a StringInitFailureKind that describes why the
62/// initialization would not work.
63static StringInitFailureKind IsStringInit(Expr *Init, const ArrayType *AT,
64 ASTContext &Context) {
65 if (!isa<ConstantArrayType>(AT) && !isa<IncompleteArrayType>(AT))
66 return SIF_Other;
67
68 // See if this is a string literal or @encode.
69 Init = Init->IgnoreParens();
70
71 // Handle @encode, which is a narrow string.
72 if (isa<ObjCEncodeExpr>(Init) && AT->getElementType()->isCharType())
73 return SIF_None;
74
75 // Otherwise we can only handle string literals.
76 StringLiteral *SL = dyn_cast<StringLiteral>(Init);
77 if (!SL)
78 return SIF_Other;
79
80 const QualType ElemTy =
81 Context.getCanonicalType(AT->getElementType()).getUnqualifiedType();
82
83 switch (SL->getKind()) {
84 case StringLiteral::UTF8:
85 // char8_t array can be initialized with a UTF-8 string.
86 if (ElemTy->isChar8Type())
87 return SIF_None;
88 LLVM_FALLTHROUGH[[gnu::fallthrough]];
89 case StringLiteral::Ascii:
90 // char array can be initialized with a narrow string.
91 // Only allow char x[] = "foo"; not char x[] = L"foo";
92 if (ElemTy->isCharType())
93 return (SL->getKind() == StringLiteral::UTF8 &&
94 Context.getLangOpts().Char8)
95 ? SIF_UTF8StringIntoPlainChar
96 : SIF_None;
97 if (ElemTy->isChar8Type())
98 return SIF_PlainStringIntoUTF8Char;
99 if (IsWideCharCompatible(ElemTy, Context))
100 return SIF_NarrowStringIntoWideChar;
101 return SIF_Other;
102 // C99 6.7.8p15 (with correction from DR343), or C11 6.7.9p15:
103 // "An array with element type compatible with a qualified or unqualified
104 // version of wchar_t, char16_t, or char32_t may be initialized by a wide
105 // string literal with the corresponding encoding prefix (L, u, or U,
106 // respectively), optionally enclosed in braces.
107 case StringLiteral::UTF16:
108 if (Context.typesAreCompatible(Context.Char16Ty, ElemTy))
109 return SIF_None;
110 if (ElemTy->isCharType() || ElemTy->isChar8Type())
111 return SIF_WideStringIntoChar;
112 if (IsWideCharCompatible(ElemTy, Context))
113 return SIF_IncompatWideStringIntoWideChar;
114 return SIF_Other;
115 case StringLiteral::UTF32:
116 if (Context.typesAreCompatible(Context.Char32Ty, ElemTy))
117 return SIF_None;
118 if (ElemTy->isCharType() || ElemTy->isChar8Type())
119 return SIF_WideStringIntoChar;
120 if (IsWideCharCompatible(ElemTy, Context))
121 return SIF_IncompatWideStringIntoWideChar;
122 return SIF_Other;
123 case StringLiteral::Wide:
124 if (Context.typesAreCompatible(Context.getWideCharType(), ElemTy))
125 return SIF_None;
126 if (ElemTy->isCharType() || ElemTy->isChar8Type())
127 return SIF_WideStringIntoChar;
128 if (IsWideCharCompatible(ElemTy, Context))
129 return SIF_IncompatWideStringIntoWideChar;
130 return SIF_Other;
131 }
132
133 llvm_unreachable("missed a StringLiteral kind?")::llvm::llvm_unreachable_internal("missed a StringLiteral kind?"
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 133)
;
134}
135
136static StringInitFailureKind IsStringInit(Expr *init, QualType declType,
137 ASTContext &Context) {
138 const ArrayType *arrayType = Context.getAsArrayType(declType);
139 if (!arrayType)
140 return SIF_Other;
141 return IsStringInit(init, arrayType, Context);
142}
143
144bool Sema::IsStringInit(Expr *Init, const ArrayType *AT) {
145 return ::IsStringInit(Init, AT, Context) == SIF_None;
146}
147
148/// Update the type of a string literal, including any surrounding parentheses,
149/// to match the type of the object which it is initializing.
150static void updateStringLiteralType(Expr *E, QualType Ty) {
151 while (true) {
152 E->setType(Ty);
153 E->setValueKind(VK_RValue);
154 if (isa<StringLiteral>(E) || isa<ObjCEncodeExpr>(E)) {
155 break;
156 } else if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
157 E = PE->getSubExpr();
158 } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
159 assert(UO->getOpcode() == UO_Extension)((UO->getOpcode() == UO_Extension) ? static_cast<void>
(0) : __assert_fail ("UO->getOpcode() == UO_Extension", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 159, __PRETTY_FUNCTION__))
;
160 E = UO->getSubExpr();
161 } else if (GenericSelectionExpr *GSE = dyn_cast<GenericSelectionExpr>(E)) {
162 E = GSE->getResultExpr();
163 } else if (ChooseExpr *CE = dyn_cast<ChooseExpr>(E)) {
164 E = CE->getChosenSubExpr();
165 } else {
166 llvm_unreachable("unexpected expr in string literal init")::llvm::llvm_unreachable_internal("unexpected expr in string literal init"
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 166)
;
167 }
168 }
169}
170
171/// Fix a compound literal initializing an array so it's correctly marked
172/// as an rvalue.
173static void updateGNUCompoundLiteralRValue(Expr *E) {
174 while (true) {
175 E->setValueKind(VK_RValue);
176 if (isa<CompoundLiteralExpr>(E)) {
177 break;
178 } else if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
179 E = PE->getSubExpr();
180 } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
181 assert(UO->getOpcode() == UO_Extension)((UO->getOpcode() == UO_Extension) ? static_cast<void>
(0) : __assert_fail ("UO->getOpcode() == UO_Extension", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 181, __PRETTY_FUNCTION__))
;
182 E = UO->getSubExpr();
183 } else if (GenericSelectionExpr *GSE = dyn_cast<GenericSelectionExpr>(E)) {
184 E = GSE->getResultExpr();
185 } else if (ChooseExpr *CE = dyn_cast<ChooseExpr>(E)) {
186 E = CE->getChosenSubExpr();
187 } else {
188 llvm_unreachable("unexpected expr in array compound literal init")::llvm::llvm_unreachable_internal("unexpected expr in array compound literal init"
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 188)
;
189 }
190 }
191}
192
193static void CheckStringInit(Expr *Str, QualType &DeclT, const ArrayType *AT,
194 Sema &S) {
195 // Get the length of the string as parsed.
196 auto *ConstantArrayTy =
197 cast<ConstantArrayType>(Str->getType()->getAsArrayTypeUnsafe());
198 uint64_t StrLength = ConstantArrayTy->getSize().getZExtValue();
199
200 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) {
201 // C99 6.7.8p14. We have an array of character type with unknown size
202 // being initialized to a string literal.
203 llvm::APInt ConstVal(32, StrLength);
204 // Return a new array type (C99 6.7.8p22).
205 DeclT = S.Context.getConstantArrayType(IAT->getElementType(),
206 ConstVal, nullptr,
207 ArrayType::Normal, 0);
208 updateStringLiteralType(Str, DeclT);
209 return;
210 }
211
212 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT);
213
214 // We have an array of character type with known size. However,
215 // the size may be smaller or larger than the string we are initializing.
216 // FIXME: Avoid truncation for 64-bit length strings.
217 if (S.getLangOpts().CPlusPlus) {
218 if (StringLiteral *SL = dyn_cast<StringLiteral>(Str->IgnoreParens())) {
219 // For Pascal strings it's OK to strip off the terminating null character,
220 // so the example below is valid:
221 //
222 // unsigned char a[2] = "\pa";
223 if (SL->isPascal())
224 StrLength--;
225 }
226
227 // [dcl.init.string]p2
228 if (StrLength > CAT->getSize().getZExtValue())
229 S.Diag(Str->getBeginLoc(),
230 diag::err_initializer_string_for_char_array_too_long)
231 << Str->getSourceRange();
232 } else {
233 // C99 6.7.8p14.
234 if (StrLength-1 > CAT->getSize().getZExtValue())
235 S.Diag(Str->getBeginLoc(),
236 diag::ext_initializer_string_for_char_array_too_long)
237 << Str->getSourceRange();
238 }
239
240 // Set the type to the actual size that we are initializing. If we have
241 // something like:
242 // char x[1] = "foo";
243 // then this will set the string literal's type to char[1].
244 updateStringLiteralType(Str, DeclT);
245}
246
247//===----------------------------------------------------------------------===//
248// Semantic checking for initializer lists.
249//===----------------------------------------------------------------------===//
250
251namespace {
252
253/// Semantic checking for initializer lists.
254///
255/// The InitListChecker class contains a set of routines that each
256/// handle the initialization of a certain kind of entity, e.g.,
257/// arrays, vectors, struct/union types, scalars, etc. The
258/// InitListChecker itself performs a recursive walk of the subobject
259/// structure of the type to be initialized, while stepping through
260/// the initializer list one element at a time. The IList and Index
261/// parameters to each of the Check* routines contain the active
262/// (syntactic) initializer list and the index into that initializer
263/// list that represents the current initializer. Each routine is
264/// responsible for moving that Index forward as it consumes elements.
265///
266/// Each Check* routine also has a StructuredList/StructuredIndex
267/// arguments, which contains the current "structured" (semantic)
268/// initializer list and the index into that initializer list where we
269/// are copying initializers as we map them over to the semantic
270/// list. Once we have completed our recursive walk of the subobject
271/// structure, we will have constructed a full semantic initializer
272/// list.
273///
274/// C99 designators cause changes in the initializer list traversal,
275/// because they make the initialization "jump" into a specific
276/// subobject and then continue the initialization from that
277/// point. CheckDesignatedInitializer() recursively steps into the
278/// designated subobject and manages backing out the recursion to
279/// initialize the subobjects after the one designated.
280///
281/// If an initializer list contains any designators, we build a placeholder
282/// structured list even in 'verify only' mode, so that we can track which
283/// elements need 'empty' initializtion.
284class InitListChecker {
285 Sema &SemaRef;
286 bool hadError = false;
287 bool VerifyOnly; // No diagnostics.
288 bool TreatUnavailableAsInvalid; // Used only in VerifyOnly mode.
289 bool InOverloadResolution;
290 InitListExpr *FullyStructuredList = nullptr;
291 NoInitExpr *DummyExpr = nullptr;
292
293 NoInitExpr *getDummyInit() {
294 if (!DummyExpr)
295 DummyExpr = new (SemaRef.Context) NoInitExpr(SemaRef.Context.VoidTy);
296 return DummyExpr;
297 }
298
299 void CheckImplicitInitList(const InitializedEntity &Entity,
300 InitListExpr *ParentIList, QualType T,
301 unsigned &Index, InitListExpr *StructuredList,
302 unsigned &StructuredIndex);
303 void CheckExplicitInitList(const InitializedEntity &Entity,
304 InitListExpr *IList, QualType &T,
305 InitListExpr *StructuredList,
306 bool TopLevelObject = false);
307 void CheckListElementTypes(const InitializedEntity &Entity,
308 InitListExpr *IList, QualType &DeclType,
309 bool SubobjectIsDesignatorContext,
310 unsigned &Index,
311 InitListExpr *StructuredList,
312 unsigned &StructuredIndex,
313 bool TopLevelObject = false);
314 void CheckSubElementType(const InitializedEntity &Entity,
315 InitListExpr *IList, QualType ElemType,
316 unsigned &Index,
317 InitListExpr *StructuredList,
318 unsigned &StructuredIndex,
319 bool DirectlyDesignated = false);
320 void CheckComplexType(const InitializedEntity &Entity,
321 InitListExpr *IList, QualType DeclType,
322 unsigned &Index,
323 InitListExpr *StructuredList,
324 unsigned &StructuredIndex);
325 void CheckScalarType(const InitializedEntity &Entity,
326 InitListExpr *IList, QualType DeclType,
327 unsigned &Index,
328 InitListExpr *StructuredList,
329 unsigned &StructuredIndex);
330 void CheckReferenceType(const InitializedEntity &Entity,
331 InitListExpr *IList, QualType DeclType,
332 unsigned &Index,
333 InitListExpr *StructuredList,
334 unsigned &StructuredIndex);
335 void CheckVectorType(const InitializedEntity &Entity,
336 InitListExpr *IList, QualType DeclType, unsigned &Index,
337 InitListExpr *StructuredList,
338 unsigned &StructuredIndex);
339 void CheckStructUnionTypes(const InitializedEntity &Entity,
340 InitListExpr *IList, QualType DeclType,
341 CXXRecordDecl::base_class_range Bases,
342 RecordDecl::field_iterator Field,
343 bool SubobjectIsDesignatorContext, unsigned &Index,
344 InitListExpr *StructuredList,
345 unsigned &StructuredIndex,
346 bool TopLevelObject = false);
347 void CheckArrayType(const InitializedEntity &Entity,
348 InitListExpr *IList, QualType &DeclType,
349 llvm::APSInt elementIndex,
350 bool SubobjectIsDesignatorContext, unsigned &Index,
351 InitListExpr *StructuredList,
352 unsigned &StructuredIndex);
353 bool CheckDesignatedInitializer(const InitializedEntity &Entity,
354 InitListExpr *IList, DesignatedInitExpr *DIE,
355 unsigned DesigIdx,
356 QualType &CurrentObjectType,
357 RecordDecl::field_iterator *NextField,
358 llvm::APSInt *NextElementIndex,
359 unsigned &Index,
360 InitListExpr *StructuredList,
361 unsigned &StructuredIndex,
362 bool FinishSubobjectInit,
363 bool TopLevelObject);
364 InitListExpr *getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
365 QualType CurrentObjectType,
366 InitListExpr *StructuredList,
367 unsigned StructuredIndex,
368 SourceRange InitRange,
369 bool IsFullyOverwritten = false);
370 void UpdateStructuredListElement(InitListExpr *StructuredList,
371 unsigned &StructuredIndex,
372 Expr *expr);
373 InitListExpr *createInitListExpr(QualType CurrentObjectType,
374 SourceRange InitRange,
375 unsigned ExpectedNumInits);
376 int numArrayElements(QualType DeclType);
377 int numStructUnionElements(QualType DeclType);
378
379 ExprResult PerformEmptyInit(SourceLocation Loc,
380 const InitializedEntity &Entity);
381
382 /// Diagnose that OldInit (or part thereof) has been overridden by NewInit.
383 void diagnoseInitOverride(Expr *OldInit, SourceRange NewInitRange,
384 bool FullyOverwritten = true) {
385 // Overriding an initializer via a designator is valid with C99 designated
386 // initializers, but ill-formed with C++20 designated initializers.
387 unsigned DiagID = SemaRef.getLangOpts().CPlusPlus
388 ? diag::ext_initializer_overrides
389 : diag::warn_initializer_overrides;
390
391 if (InOverloadResolution && SemaRef.getLangOpts().CPlusPlus) {
392 // In overload resolution, we have to strictly enforce the rules, and so
393 // don't allow any overriding of prior initializers. This matters for a
394 // case such as:
395 //
396 // union U { int a, b; };
397 // struct S { int a, b; };
398 // void f(U), f(S);
399 //
400 // Here, f({.a = 1, .b = 2}) is required to call the struct overload. For
401 // consistency, we disallow all overriding of prior initializers in
402 // overload resolution, not only overriding of union members.
403 hadError = true;
404 } else if (OldInit->getType().isDestructedType() && !FullyOverwritten) {
405 // If we'll be keeping around the old initializer but overwriting part of
406 // the object it initialized, and that object is not trivially
407 // destructible, this can leak. Don't allow that, not even as an
408 // extension.
409 //
410 // FIXME: It might be reasonable to allow this in cases where the part of
411 // the initializer that we're overriding has trivial destruction.
412 DiagID = diag::err_initializer_overrides_destructed;
413 } else if (!OldInit->getSourceRange().isValid()) {
414 // We need to check on source range validity because the previous
415 // initializer does not have to be an explicit initializer. e.g.,
416 //
417 // struct P { int a, b; };
418 // struct PP { struct P p } l = { { .a = 2 }, .p.b = 3 };
419 //
420 // There is an overwrite taking place because the first braced initializer
421 // list "{ .a = 2 }" already provides value for .p.b (which is zero).
422 //
423 // Such overwrites are harmless, so we don't diagnose them. (Note that in
424 // C++, this cannot be reached unless we've already seen and diagnosed a
425 // different conformance issue, such as a mixture of designated and
426 // non-designated initializers or a multi-level designator.)
427 return;
428 }
429
430 if (!VerifyOnly) {
431 SemaRef.Diag(NewInitRange.getBegin(), DiagID)
432 << NewInitRange << FullyOverwritten << OldInit->getType();
433 SemaRef.Diag(OldInit->getBeginLoc(), diag::note_previous_initializer)
434 << (OldInit->HasSideEffects(SemaRef.Context) && FullyOverwritten)
435 << OldInit->getSourceRange();
436 }
437 }
438
439 // Explanation on the "FillWithNoInit" mode:
440 //
441 // Assume we have the following definitions (Case#1):
442 // struct P { char x[6][6]; } xp = { .x[1] = "bar" };
443 // struct PP { struct P lp; } l = { .lp = xp, .lp.x[1][2] = 'f' };
444 //
445 // l.lp.x[1][0..1] should not be filled with implicit initializers because the
446 // "base" initializer "xp" will provide values for them; l.lp.x[1] will be "baf".
447 //
448 // But if we have (Case#2):
449 // struct PP l = { .lp = xp, .lp.x[1] = { [2] = 'f' } };
450 //
451 // l.lp.x[1][0..1] are implicitly initialized and do not use values from the
452 // "base" initializer; l.lp.x[1] will be "\0\0f\0\0\0".
453 //
454 // To distinguish Case#1 from Case#2, and also to avoid leaving many "holes"
455 // in the InitListExpr, the "holes" in Case#1 are filled not with empty
456 // initializers but with special "NoInitExpr" place holders, which tells the
457 // CodeGen not to generate any initializers for these parts.
458 void FillInEmptyInitForBase(unsigned Init, const CXXBaseSpecifier &Base,
459 const InitializedEntity &ParentEntity,
460 InitListExpr *ILE, bool &RequiresSecondPass,
461 bool FillWithNoInit);
462 void FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
463 const InitializedEntity &ParentEntity,
464 InitListExpr *ILE, bool &RequiresSecondPass,
465 bool FillWithNoInit = false);
466 void FillInEmptyInitializations(const InitializedEntity &Entity,
467 InitListExpr *ILE, bool &RequiresSecondPass,
468 InitListExpr *OuterILE, unsigned OuterIndex,
469 bool FillWithNoInit = false);
470 bool CheckFlexibleArrayInit(const InitializedEntity &Entity,
471 Expr *InitExpr, FieldDecl *Field,
472 bool TopLevelObject);
473 void CheckEmptyInitializable(const InitializedEntity &Entity,
474 SourceLocation Loc);
475
476public:
477 InitListChecker(Sema &S, const InitializedEntity &Entity, InitListExpr *IL,
478 QualType &T, bool VerifyOnly, bool TreatUnavailableAsInvalid,
479 bool InOverloadResolution = false);
480 bool HadError() { return hadError; }
481
482 // Retrieves the fully-structured initializer list used for
483 // semantic analysis and code generation.
484 InitListExpr *getFullyStructuredList() const { return FullyStructuredList; }
485};
486
487} // end anonymous namespace
488
489ExprResult InitListChecker::PerformEmptyInit(SourceLocation Loc,
490 const InitializedEntity &Entity) {
491 InitializationKind Kind = InitializationKind::CreateValue(Loc, Loc, Loc,
492 true);
493 MultiExprArg SubInit;
494 Expr *InitExpr;
495 InitListExpr DummyInitList(SemaRef.Context, Loc, None, Loc);
496
497 // C++ [dcl.init.aggr]p7:
498 // If there are fewer initializer-clauses in the list than there are
499 // members in the aggregate, then each member not explicitly initialized
500 // ...
501 bool EmptyInitList = SemaRef.getLangOpts().CPlusPlus11 &&
502 Entity.getType()->getBaseElementTypeUnsafe()->isRecordType();
503 if (EmptyInitList) {
504 // C++1y / DR1070:
505 // shall be initialized [...] from an empty initializer list.
506 //
507 // We apply the resolution of this DR to C++11 but not C++98, since C++98
508 // does not have useful semantics for initialization from an init list.
509 // We treat this as copy-initialization, because aggregate initialization
510 // always performs copy-initialization on its elements.
511 //
512 // Only do this if we're initializing a class type, to avoid filling in
513 // the initializer list where possible.
514 InitExpr = VerifyOnly ? &DummyInitList : new (SemaRef.Context)
515 InitListExpr(SemaRef.Context, Loc, None, Loc);
516 InitExpr->setType(SemaRef.Context.VoidTy);
517 SubInit = InitExpr;
518 Kind = InitializationKind::CreateCopy(Loc, Loc);
519 } else {
520 // C++03:
521 // shall be value-initialized.
522 }
523
524 InitializationSequence InitSeq(SemaRef, Entity, Kind, SubInit);
525 // libstdc++4.6 marks the vector default constructor as explicit in
526 // _GLIBCXX_DEBUG mode, so recover using the C++03 logic in that case.
527 // stlport does so too. Look for std::__debug for libstdc++, and for
528 // std:: for stlport. This is effectively a compiler-side implementation of
529 // LWG2193.
530 if (!InitSeq && EmptyInitList && InitSeq.getFailureKind() ==
531 InitializationSequence::FK_ExplicitConstructor) {
532 OverloadCandidateSet::iterator Best;
533 OverloadingResult O =
534 InitSeq.getFailedCandidateSet()
535 .BestViableFunction(SemaRef, Kind.getLocation(), Best);
536 (void)O;
537 assert(O == OR_Success && "Inconsistent overload resolution")((O == OR_Success && "Inconsistent overload resolution"
) ? static_cast<void> (0) : __assert_fail ("O == OR_Success && \"Inconsistent overload resolution\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 537, __PRETTY_FUNCTION__))
;
538 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
539 CXXRecordDecl *R = CtorDecl->getParent();
540
541 if (CtorDecl->getMinRequiredArguments() == 0 &&
542 CtorDecl->isExplicit() && R->getDeclName() &&
543 SemaRef.SourceMgr.isInSystemHeader(CtorDecl->getLocation())) {
544 bool IsInStd = false;
545 for (NamespaceDecl *ND = dyn_cast<NamespaceDecl>(R->getDeclContext());
546 ND && !IsInStd; ND = dyn_cast<NamespaceDecl>(ND->getParent())) {
547 if (SemaRef.getStdNamespace()->InEnclosingNamespaceSetOf(ND))
548 IsInStd = true;
549 }
550
551 if (IsInStd && llvm::StringSwitch<bool>(R->getName())
552 .Cases("basic_string", "deque", "forward_list", true)
553 .Cases("list", "map", "multimap", "multiset", true)
554 .Cases("priority_queue", "queue", "set", "stack", true)
555 .Cases("unordered_map", "unordered_set", "vector", true)
556 .Default(false)) {
557 InitSeq.InitializeFrom(
558 SemaRef, Entity,
559 InitializationKind::CreateValue(Loc, Loc, Loc, true),
560 MultiExprArg(), /*TopLevelOfInitList=*/false,
561 TreatUnavailableAsInvalid);
562 // Emit a warning for this. System header warnings aren't shown
563 // by default, but people working on system headers should see it.
564 if (!VerifyOnly) {
565 SemaRef.Diag(CtorDecl->getLocation(),
566 diag::warn_invalid_initializer_from_system_header);
567 if (Entity.getKind() == InitializedEntity::EK_Member)
568 SemaRef.Diag(Entity.getDecl()->getLocation(),
569 diag::note_used_in_initialization_here);
570 else if (Entity.getKind() == InitializedEntity::EK_ArrayElement)
571 SemaRef.Diag(Loc, diag::note_used_in_initialization_here);
572 }
573 }
574 }
575 }
576 if (!InitSeq) {
577 if (!VerifyOnly) {
578 InitSeq.Diagnose(SemaRef, Entity, Kind, SubInit);
579 if (Entity.getKind() == InitializedEntity::EK_Member)
580 SemaRef.Diag(Entity.getDecl()->getLocation(),
581 diag::note_in_omitted_aggregate_initializer)
582 << /*field*/1 << Entity.getDecl();
583 else if (Entity.getKind() == InitializedEntity::EK_ArrayElement) {
584 bool IsTrailingArrayNewMember =
585 Entity.getParent() &&
586 Entity.getParent()->isVariableLengthArrayNew();
587 SemaRef.Diag(Loc, diag::note_in_omitted_aggregate_initializer)
588 << (IsTrailingArrayNewMember ? 2 : /*array element*/0)
589 << Entity.getElementIndex();
590 }
591 }
592 hadError = true;
593 return ExprError();
594 }
595
596 return VerifyOnly ? ExprResult()
597 : InitSeq.Perform(SemaRef, Entity, Kind, SubInit);
598}
599
600void InitListChecker::CheckEmptyInitializable(const InitializedEntity &Entity,
601 SourceLocation Loc) {
602 // If we're building a fully-structured list, we'll check this at the end
603 // once we know which elements are actually initialized. Otherwise, we know
604 // that there are no designators so we can just check now.
605 if (FullyStructuredList)
606 return;
607 PerformEmptyInit(Loc, Entity);
608}
609
610void InitListChecker::FillInEmptyInitForBase(
611 unsigned Init, const CXXBaseSpecifier &Base,
612 const InitializedEntity &ParentEntity, InitListExpr *ILE,
613 bool &RequiresSecondPass, bool FillWithNoInit) {
614 InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
615 SemaRef.Context, &Base, false, &ParentEntity);
616
617 if (Init >= ILE->getNumInits() || !ILE->getInit(Init)) {
618 ExprResult BaseInit = FillWithNoInit
619 ? new (SemaRef.Context) NoInitExpr(Base.getType())
620 : PerformEmptyInit(ILE->getEndLoc(), BaseEntity);
621 if (BaseInit.isInvalid()) {
622 hadError = true;
623 return;
624 }
625
626 if (!VerifyOnly) {
627 assert(Init < ILE->getNumInits() && "should have been expanded")((Init < ILE->getNumInits() && "should have been expanded"
) ? static_cast<void> (0) : __assert_fail ("Init < ILE->getNumInits() && \"should have been expanded\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 627, __PRETTY_FUNCTION__))
;
628 ILE->setInit(Init, BaseInit.getAs<Expr>());
629 }
630 } else if (InitListExpr *InnerILE =
631 dyn_cast<InitListExpr>(ILE->getInit(Init))) {
632 FillInEmptyInitializations(BaseEntity, InnerILE, RequiresSecondPass,
633 ILE, Init, FillWithNoInit);
634 } else if (DesignatedInitUpdateExpr *InnerDIUE =
635 dyn_cast<DesignatedInitUpdateExpr>(ILE->getInit(Init))) {
636 FillInEmptyInitializations(BaseEntity, InnerDIUE->getUpdater(),
637 RequiresSecondPass, ILE, Init,
638 /*FillWithNoInit =*/true);
639 }
640}
641
642void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
643 const InitializedEntity &ParentEntity,
644 InitListExpr *ILE,
645 bool &RequiresSecondPass,
646 bool FillWithNoInit) {
647 SourceLocation Loc = ILE->getEndLoc();
648 unsigned NumInits = ILE->getNumInits();
649 InitializedEntity MemberEntity
650 = InitializedEntity::InitializeMember(Field, &ParentEntity);
651
652 if (Init >= NumInits || !ILE->getInit(Init)) {
653 if (const RecordType *RType = ILE->getType()->getAs<RecordType>())
654 if (!RType->getDecl()->isUnion())
655 assert((Init < NumInits || VerifyOnly) &&(((Init < NumInits || VerifyOnly) && "This ILE should have been expanded"
) ? static_cast<void> (0) : __assert_fail ("(Init < NumInits || VerifyOnly) && \"This ILE should have been expanded\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 656, __PRETTY_FUNCTION__))
656 "This ILE should have been expanded")(((Init < NumInits || VerifyOnly) && "This ILE should have been expanded"
) ? static_cast<void> (0) : __assert_fail ("(Init < NumInits || VerifyOnly) && \"This ILE should have been expanded\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 656, __PRETTY_FUNCTION__))
;
657
658 if (FillWithNoInit) {
659 assert(!VerifyOnly && "should not fill with no-init in verify-only mode")((!VerifyOnly && "should not fill with no-init in verify-only mode"
) ? static_cast<void> (0) : __assert_fail ("!VerifyOnly && \"should not fill with no-init in verify-only mode\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 659, __PRETTY_FUNCTION__))
;
660 Expr *Filler = new (SemaRef.Context) NoInitExpr(Field->getType());
661 if (Init < NumInits)
662 ILE->setInit(Init, Filler);
663 else
664 ILE->updateInit(SemaRef.Context, Init, Filler);
665 return;
666 }
667 // C++1y [dcl.init.aggr]p7:
668 // If there are fewer initializer-clauses in the list than there are
669 // members in the aggregate, then each member not explicitly initialized
670 // shall be initialized from its brace-or-equal-initializer [...]
671 if (Field->hasInClassInitializer()) {
672 if (VerifyOnly)
673 return;
674
675 ExprResult DIE = SemaRef.BuildCXXDefaultInitExpr(Loc, Field);
676 if (DIE.isInvalid()) {
677 hadError = true;
678 return;
679 }
680 SemaRef.checkInitializerLifetime(MemberEntity, DIE.get());
681 if (Init < NumInits)
682 ILE->setInit(Init, DIE.get());
683 else {
684 ILE->updateInit(SemaRef.Context, Init, DIE.get());
685 RequiresSecondPass = true;
686 }
687 return;
688 }
689
690 if (Field->getType()->isReferenceType()) {
691 if (!VerifyOnly) {
692 // C++ [dcl.init.aggr]p9:
693 // If an incomplete or empty initializer-list leaves a
694 // member of reference type uninitialized, the program is
695 // ill-formed.
696 SemaRef.Diag(Loc, diag::err_init_reference_member_uninitialized)
697 << Field->getType()
698 << ILE->getSyntacticForm()->getSourceRange();
699 SemaRef.Diag(Field->getLocation(),
700 diag::note_uninit_reference_member);
701 }
702 hadError = true;
703 return;
704 }
705
706 ExprResult MemberInit = PerformEmptyInit(Loc, MemberEntity);
707 if (MemberInit.isInvalid()) {
708 hadError = true;
709 return;
710 }
711
712 if (hadError || VerifyOnly) {
713 // Do nothing
714 } else if (Init < NumInits) {
715 ILE->setInit(Init, MemberInit.getAs<Expr>());
716 } else if (!isa<ImplicitValueInitExpr>(MemberInit.get())) {
717 // Empty initialization requires a constructor call, so
718 // extend the initializer list to include the constructor
719 // call and make a note that we'll need to take another pass
720 // through the initializer list.
721 ILE->updateInit(SemaRef.Context, Init, MemberInit.getAs<Expr>());
722 RequiresSecondPass = true;
723 }
724 } else if (InitListExpr *InnerILE
725 = dyn_cast<InitListExpr>(ILE->getInit(Init))) {
726 FillInEmptyInitializations(MemberEntity, InnerILE,
727 RequiresSecondPass, ILE, Init, FillWithNoInit);
728 } else if (DesignatedInitUpdateExpr *InnerDIUE =
729 dyn_cast<DesignatedInitUpdateExpr>(ILE->getInit(Init))) {
730 FillInEmptyInitializations(MemberEntity, InnerDIUE->getUpdater(),
731 RequiresSecondPass, ILE, Init,
732 /*FillWithNoInit =*/true);
733 }
734}
735
736/// Recursively replaces NULL values within the given initializer list
737/// with expressions that perform value-initialization of the
738/// appropriate type, and finish off the InitListExpr formation.
739void
740InitListChecker::FillInEmptyInitializations(const InitializedEntity &Entity,
741 InitListExpr *ILE,
742 bool &RequiresSecondPass,
743 InitListExpr *OuterILE,
744 unsigned OuterIndex,
745 bool FillWithNoInit) {
746 assert((ILE->getType() != SemaRef.Context.VoidTy) &&(((ILE->getType() != SemaRef.Context.VoidTy) && "Should not have void type"
) ? static_cast<void> (0) : __assert_fail ("(ILE->getType() != SemaRef.Context.VoidTy) && \"Should not have void type\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 747, __PRETTY_FUNCTION__))
747 "Should not have void type")(((ILE->getType() != SemaRef.Context.VoidTy) && "Should not have void type"
) ? static_cast<void> (0) : __assert_fail ("(ILE->getType() != SemaRef.Context.VoidTy) && \"Should not have void type\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 747, __PRETTY_FUNCTION__))
;
748
749 // We don't need to do any checks when just filling NoInitExprs; that can't
750 // fail.
751 if (FillWithNoInit && VerifyOnly)
752 return;
753
754 // If this is a nested initializer list, we might have changed its contents
755 // (and therefore some of its properties, such as instantiation-dependence)
756 // while filling it in. Inform the outer initializer list so that its state
757 // can be updated to match.
758 // FIXME: We should fully build the inner initializers before constructing
759 // the outer InitListExpr instead of mutating AST nodes after they have
760 // been used as subexpressions of other nodes.
761 struct UpdateOuterILEWithUpdatedInit {
762 InitListExpr *Outer;
763 unsigned OuterIndex;
764 ~UpdateOuterILEWithUpdatedInit() {
765 if (Outer)
766 Outer->setInit(OuterIndex, Outer->getInit(OuterIndex));
767 }
768 } UpdateOuterRAII = {OuterILE, OuterIndex};
769
770 // A transparent ILE is not performing aggregate initialization and should
771 // not be filled in.
772 if (ILE->isTransparent())
773 return;
774
775 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
776 const RecordDecl *RDecl = RType->getDecl();
777 if (RDecl->isUnion() && ILE->getInitializedFieldInUnion())
778 FillInEmptyInitForField(0, ILE->getInitializedFieldInUnion(),
779 Entity, ILE, RequiresSecondPass, FillWithNoInit);
780 else if (RDecl->isUnion() && isa<CXXRecordDecl>(RDecl) &&
781 cast<CXXRecordDecl>(RDecl)->hasInClassInitializer()) {
782 for (auto *Field : RDecl->fields()) {
783 if (Field->hasInClassInitializer()) {
784 FillInEmptyInitForField(0, Field, Entity, ILE, RequiresSecondPass,
785 FillWithNoInit);
786 break;
787 }
788 }
789 } else {
790 // The fields beyond ILE->getNumInits() are default initialized, so in
791 // order to leave them uninitialized, the ILE is expanded and the extra
792 // fields are then filled with NoInitExpr.
793 unsigned NumElems = numStructUnionElements(ILE->getType());
794 if (RDecl->hasFlexibleArrayMember())
795 ++NumElems;
796 if (!VerifyOnly && ILE->getNumInits() < NumElems)
797 ILE->resizeInits(SemaRef.Context, NumElems);
798
799 unsigned Init = 0;
800
801 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RDecl)) {
802 for (auto &Base : CXXRD->bases()) {
803 if (hadError)
804 return;
805
806 FillInEmptyInitForBase(Init, Base, Entity, ILE, RequiresSecondPass,
807 FillWithNoInit);
808 ++Init;
809 }
810 }
811
812 for (auto *Field : RDecl->fields()) {
813 if (Field->isUnnamedBitfield())
814 continue;
815
816 if (hadError)
817 return;
818
819 FillInEmptyInitForField(Init, Field, Entity, ILE, RequiresSecondPass,
820 FillWithNoInit);
821 if (hadError)
822 return;
823
824 ++Init;
825
826 // Only look at the first initialization of a union.
827 if (RDecl->isUnion())
828 break;
829 }
830 }
831
832 return;
833 }
834
835 QualType ElementType;
836
837 InitializedEntity ElementEntity = Entity;
838 unsigned NumInits = ILE->getNumInits();
839 unsigned NumElements = NumInits;
840 if (const ArrayType *AType = SemaRef.Context.getAsArrayType(ILE->getType())) {
841 ElementType = AType->getElementType();
842 if (const auto *CAType = dyn_cast<ConstantArrayType>(AType))
843 NumElements = CAType->getSize().getZExtValue();
844 // For an array new with an unknown bound, ask for one additional element
845 // in order to populate the array filler.
846 if (Entity.isVariableLengthArrayNew())
847 ++NumElements;
848 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
849 0, Entity);
850 } else if (const VectorType *VType = ILE->getType()->getAs<VectorType>()) {
851 ElementType = VType->getElementType();
852 NumElements = VType->getNumElements();
853 ElementEntity = InitializedEntity::InitializeElement(SemaRef.Context,
854 0, Entity);
855 } else
856 ElementType = ILE->getType();
857
858 bool SkipEmptyInitChecks = false;
859 for (unsigned Init = 0; Init != NumElements; ++Init) {
860 if (hadError)
861 return;
862
863 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement ||
864 ElementEntity.getKind() == InitializedEntity::EK_VectorElement)
865 ElementEntity.setElementIndex(Init);
866
867 if (Init >= NumInits && (ILE->hasArrayFiller() || SkipEmptyInitChecks))
868 return;
869
870 Expr *InitExpr = (Init < NumInits ? ILE->getInit(Init) : nullptr);
871 if (!InitExpr && Init < NumInits && ILE->hasArrayFiller())
872 ILE->setInit(Init, ILE->getArrayFiller());
873 else if (!InitExpr && !ILE->hasArrayFiller()) {
874 // In VerifyOnly mode, there's no point performing empty initialization
875 // more than once.
876 if (SkipEmptyInitChecks)
877 continue;
878
879 Expr *Filler = nullptr;
880
881 if (FillWithNoInit)
882 Filler = new (SemaRef.Context) NoInitExpr(ElementType);
883 else {
884 ExprResult ElementInit =
885 PerformEmptyInit(ILE->getEndLoc(), ElementEntity);
886 if (ElementInit.isInvalid()) {
887 hadError = true;
888 return;
889 }
890
891 Filler = ElementInit.getAs<Expr>();
892 }
893
894 if (hadError) {
895 // Do nothing
896 } else if (VerifyOnly) {
897 SkipEmptyInitChecks = true;
898 } else if (Init < NumInits) {
899 // For arrays, just set the expression used for value-initialization
900 // of the "holes" in the array.
901 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement)
902 ILE->setArrayFiller(Filler);
903 else
904 ILE->setInit(Init, Filler);
905 } else {
906 // For arrays, just set the expression used for value-initialization
907 // of the rest of elements and exit.
908 if (ElementEntity.getKind() == InitializedEntity::EK_ArrayElement) {
909 ILE->setArrayFiller(Filler);
910 return;
911 }
912
913 if (!isa<ImplicitValueInitExpr>(Filler) && !isa<NoInitExpr>(Filler)) {
914 // Empty initialization requires a constructor call, so
915 // extend the initializer list to include the constructor
916 // call and make a note that we'll need to take another pass
917 // through the initializer list.
918 ILE->updateInit(SemaRef.Context, Init, Filler);
919 RequiresSecondPass = true;
920 }
921 }
922 } else if (InitListExpr *InnerILE
923 = dyn_cast_or_null<InitListExpr>(InitExpr)) {
924 FillInEmptyInitializations(ElementEntity, InnerILE, RequiresSecondPass,
925 ILE, Init, FillWithNoInit);
926 } else if (DesignatedInitUpdateExpr *InnerDIUE =
927 dyn_cast_or_null<DesignatedInitUpdateExpr>(InitExpr)) {
928 FillInEmptyInitializations(ElementEntity, InnerDIUE->getUpdater(),
929 RequiresSecondPass, ILE, Init,
930 /*FillWithNoInit =*/true);
931 }
932 }
933}
934
935static bool hasAnyDesignatedInits(const InitListExpr *IL) {
936 for (const Stmt *Init : *IL)
937 if (Init && isa<DesignatedInitExpr>(Init))
938 return true;
939 return false;
940}
941
942InitListChecker::InitListChecker(Sema &S, const InitializedEntity &Entity,
943 InitListExpr *IL, QualType &T, bool VerifyOnly,
944 bool TreatUnavailableAsInvalid,
945 bool InOverloadResolution)
946 : SemaRef(S), VerifyOnly(VerifyOnly),
947 TreatUnavailableAsInvalid(TreatUnavailableAsInvalid),
948 InOverloadResolution(InOverloadResolution) {
949 if (!VerifyOnly || hasAnyDesignatedInits(IL)) {
950 FullyStructuredList =
951 createInitListExpr(T, IL->getSourceRange(), IL->getNumInits());
952
953 // FIXME: Check that IL isn't already the semantic form of some other
954 // InitListExpr. If it is, we'd create a broken AST.
955 if (!VerifyOnly)
956 FullyStructuredList->setSyntacticForm(IL);
957 }
958
959 CheckExplicitInitList(Entity, IL, T, FullyStructuredList,
960 /*TopLevelObject=*/true);
961
962 if (!hadError && FullyStructuredList) {
963 bool RequiresSecondPass = false;
964 FillInEmptyInitializations(Entity, FullyStructuredList, RequiresSecondPass,
965 /*OuterILE=*/nullptr, /*OuterIndex=*/0);
966 if (RequiresSecondPass && !hadError)
967 FillInEmptyInitializations(Entity, FullyStructuredList,
968 RequiresSecondPass, nullptr, 0);
969 }
970 if (hadError && FullyStructuredList)
971 FullyStructuredList->markError();
972}
973
974int InitListChecker::numArrayElements(QualType DeclType) {
975 // FIXME: use a proper constant
976 int maxElements = 0x7FFFFFFF;
977 if (const ConstantArrayType *CAT =
978 SemaRef.Context.getAsConstantArrayType(DeclType)) {
979 maxElements = static_cast<int>(CAT->getSize().getZExtValue());
980 }
981 return maxElements;
982}
983
984int InitListChecker::numStructUnionElements(QualType DeclType) {
985 RecordDecl *structDecl = DeclType->castAs<RecordType>()->getDecl();
986 int InitializableMembers = 0;
987 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(structDecl))
988 InitializableMembers += CXXRD->getNumBases();
989 for (const auto *Field : structDecl->fields())
990 if (!Field->isUnnamedBitfield())
991 ++InitializableMembers;
992
993 if (structDecl->isUnion())
994 return std::min(InitializableMembers, 1);
995 return InitializableMembers - structDecl->hasFlexibleArrayMember();
996}
997
998/// Determine whether Entity is an entity for which it is idiomatic to elide
999/// the braces in aggregate initialization.
1000static bool isIdiomaticBraceElisionEntity(const InitializedEntity &Entity) {
1001 // Recursive initialization of the one and only field within an aggregate
1002 // class is considered idiomatic. This case arises in particular for
1003 // initialization of std::array, where the C++ standard suggests the idiom of
1004 //
1005 // std::array<T, N> arr = {1, 2, 3};
1006 //
1007 // (where std::array is an aggregate struct containing a single array field.
1008
1009 // FIXME: Should aggregate initialization of a struct with a single
1010 // base class and no members also suppress the warning?
1011 if (Entity.getKind() != InitializedEntity::EK_Member || !Entity.getParent())
1012 return false;
1013
1014 auto *ParentRD =
1015 Entity.getParent()->getType()->castAs<RecordType>()->getDecl();
1016 if (CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(ParentRD))
1017 if (CXXRD->getNumBases())
1018 return false;
1019
1020 auto FieldIt = ParentRD->field_begin();
1021 assert(FieldIt != ParentRD->field_end() &&((FieldIt != ParentRD->field_end() && "no fields but have initializer for member?"
) ? static_cast<void> (0) : __assert_fail ("FieldIt != ParentRD->field_end() && \"no fields but have initializer for member?\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1022, __PRETTY_FUNCTION__))
1022 "no fields but have initializer for member?")((FieldIt != ParentRD->field_end() && "no fields but have initializer for member?"
) ? static_cast<void> (0) : __assert_fail ("FieldIt != ParentRD->field_end() && \"no fields but have initializer for member?\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1022, __PRETTY_FUNCTION__))
;
1023 return ++FieldIt == ParentRD->field_end();
1024}
1025
1026/// Check whether the range of the initializer \p ParentIList from element
1027/// \p Index onwards can be used to initialize an object of type \p T. Update
1028/// \p Index to indicate how many elements of the list were consumed.
1029///
1030/// This also fills in \p StructuredList, from element \p StructuredIndex
1031/// onwards, with the fully-braced, desugared form of the initialization.
1032void InitListChecker::CheckImplicitInitList(const InitializedEntity &Entity,
1033 InitListExpr *ParentIList,
1034 QualType T, unsigned &Index,
1035 InitListExpr *StructuredList,
1036 unsigned &StructuredIndex) {
1037 int maxElements = 0;
1038
1039 if (T->isArrayType())
1040 maxElements = numArrayElements(T);
1041 else if (T->isRecordType())
1042 maxElements = numStructUnionElements(T);
1043 else if (T->isVectorType())
1044 maxElements = T->castAs<VectorType>()->getNumElements();
1045 else
1046 llvm_unreachable("CheckImplicitInitList(): Illegal type")::llvm::llvm_unreachable_internal("CheckImplicitInitList(): Illegal type"
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1046)
;
1047
1048 if (maxElements == 0) {
1049 if (!VerifyOnly)
1050 SemaRef.Diag(ParentIList->getInit(Index)->getBeginLoc(),
1051 diag::err_implicit_empty_initializer);
1052 ++Index;
1053 hadError = true;
1054 return;
1055 }
1056
1057 // Build a structured initializer list corresponding to this subobject.
1058 InitListExpr *StructuredSubobjectInitList = getStructuredSubobjectInit(
1059 ParentIList, Index, T, StructuredList, StructuredIndex,
1060 SourceRange(ParentIList->getInit(Index)->getBeginLoc(),
1061 ParentIList->getSourceRange().getEnd()));
1062 unsigned StructuredSubobjectInitIndex = 0;
1063
1064 // Check the element types and build the structural subobject.
1065 unsigned StartIndex = Index;
1066 CheckListElementTypes(Entity, ParentIList, T,
1067 /*SubobjectIsDesignatorContext=*/false, Index,
1068 StructuredSubobjectInitList,
1069 StructuredSubobjectInitIndex);
1070
1071 if (StructuredSubobjectInitList) {
1072 StructuredSubobjectInitList->setType(T);
1073
1074 unsigned EndIndex = (Index == StartIndex? StartIndex : Index - 1);
1075 // Update the structured sub-object initializer so that it's ending
1076 // range corresponds with the end of the last initializer it used.
1077 if (EndIndex < ParentIList->getNumInits() &&
1078 ParentIList->getInit(EndIndex)) {
1079 SourceLocation EndLoc
1080 = ParentIList->getInit(EndIndex)->getSourceRange().getEnd();
1081 StructuredSubobjectInitList->setRBraceLoc(EndLoc);
1082 }
1083
1084 // Complain about missing braces.
1085 if (!VerifyOnly && (T->isArrayType() || T->isRecordType()) &&
1086 !ParentIList->isIdiomaticZeroInitializer(SemaRef.getLangOpts()) &&
1087 !isIdiomaticBraceElisionEntity(Entity)) {
1088 SemaRef.Diag(StructuredSubobjectInitList->getBeginLoc(),
1089 diag::warn_missing_braces)
1090 << StructuredSubobjectInitList->getSourceRange()
1091 << FixItHint::CreateInsertion(
1092 StructuredSubobjectInitList->getBeginLoc(), "{")
1093 << FixItHint::CreateInsertion(
1094 SemaRef.getLocForEndOfToken(
1095 StructuredSubobjectInitList->getEndLoc()),
1096 "}");
1097 }
1098
1099 // Warn if this type won't be an aggregate in future versions of C++.
1100 auto *CXXRD = T->getAsCXXRecordDecl();
1101 if (!VerifyOnly && CXXRD && CXXRD->hasUserDeclaredConstructor()) {
1102 SemaRef.Diag(StructuredSubobjectInitList->getBeginLoc(),
1103 diag::warn_cxx20_compat_aggregate_init_with_ctors)
1104 << StructuredSubobjectInitList->getSourceRange() << T;
1105 }
1106 }
1107}
1108
1109/// Warn that \p Entity was of scalar type and was initialized by a
1110/// single-element braced initializer list.
1111static void warnBracedScalarInit(Sema &S, const InitializedEntity &Entity,
1112 SourceRange Braces) {
1113 // Don't warn during template instantiation. If the initialization was
1114 // non-dependent, we warned during the initial parse; otherwise, the
1115 // type might not be scalar in some uses of the template.
1116 if (S.inTemplateInstantiation())
1117 return;
1118
1119 unsigned DiagID = 0;
1120
1121 switch (Entity.getKind()) {
1122 case InitializedEntity::EK_VectorElement:
1123 case InitializedEntity::EK_ComplexElement:
1124 case InitializedEntity::EK_ArrayElement:
1125 case InitializedEntity::EK_Parameter:
1126 case InitializedEntity::EK_Parameter_CF_Audited:
1127 case InitializedEntity::EK_TemplateParameter:
1128 case InitializedEntity::EK_Result:
1129 // Extra braces here are suspicious.
1130 DiagID = diag::warn_braces_around_init;
1131 break;
1132
1133 case InitializedEntity::EK_Member:
1134 // Warn on aggregate initialization but not on ctor init list or
1135 // default member initializer.
1136 if (Entity.getParent())
1137 DiagID = diag::warn_braces_around_init;
1138 break;
1139
1140 case InitializedEntity::EK_Variable:
1141 case InitializedEntity::EK_LambdaCapture:
1142 // No warning, might be direct-list-initialization.
1143 // FIXME: Should we warn for copy-list-initialization in these cases?
1144 break;
1145
1146 case InitializedEntity::EK_New:
1147 case InitializedEntity::EK_Temporary:
1148 case InitializedEntity::EK_CompoundLiteralInit:
1149 // No warning, braces are part of the syntax of the underlying construct.
1150 break;
1151
1152 case InitializedEntity::EK_RelatedResult:
1153 // No warning, we already warned when initializing the result.
1154 break;
1155
1156 case InitializedEntity::EK_Exception:
1157 case InitializedEntity::EK_Base:
1158 case InitializedEntity::EK_Delegating:
1159 case InitializedEntity::EK_BlockElement:
1160 case InitializedEntity::EK_LambdaToBlockConversionBlockElement:
1161 case InitializedEntity::EK_Binding:
1162 case InitializedEntity::EK_StmtExprResult:
1163 llvm_unreachable("unexpected braced scalar init")::llvm::llvm_unreachable_internal("unexpected braced scalar init"
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1163)
;
1164 }
1165
1166 if (DiagID) {
1167 S.Diag(Braces.getBegin(), DiagID)
1168 << Entity.getType()->isSizelessBuiltinType() << Braces
1169 << FixItHint::CreateRemoval(Braces.getBegin())
1170 << FixItHint::CreateRemoval(Braces.getEnd());
1171 }
1172}
1173
1174/// Check whether the initializer \p IList (that was written with explicit
1175/// braces) can be used to initialize an object of type \p T.
1176///
1177/// This also fills in \p StructuredList with the fully-braced, desugared
1178/// form of the initialization.
1179void InitListChecker::CheckExplicitInitList(const InitializedEntity &Entity,
1180 InitListExpr *IList, QualType &T,
1181 InitListExpr *StructuredList,
1182 bool TopLevelObject) {
1183 unsigned Index = 0, StructuredIndex = 0;
1184 CheckListElementTypes(Entity, IList, T, /*SubobjectIsDesignatorContext=*/true,
1185 Index, StructuredList, StructuredIndex, TopLevelObject);
1186 if (StructuredList) {
1187 QualType ExprTy = T;
1188 if (!ExprTy->isArrayType())
1189 ExprTy = ExprTy.getNonLValueExprType(SemaRef.Context);
1190 if (!VerifyOnly)
1191 IList->setType(ExprTy);
1192 StructuredList->setType(ExprTy);
1193 }
1194 if (hadError)
1195 return;
1196
1197 // Don't complain for incomplete types, since we'll get an error elsewhere.
1198 if (Index < IList->getNumInits() && !T->isIncompleteType()) {
1199 // We have leftover initializers
1200 bool ExtraInitsIsError = SemaRef.getLangOpts().CPlusPlus ||
1201 (SemaRef.getLangOpts().OpenCL && T->isVectorType());
1202 hadError = ExtraInitsIsError;
1203 if (VerifyOnly) {
1204 return;
1205 } else if (StructuredIndex == 1 &&
1206 IsStringInit(StructuredList->getInit(0), T, SemaRef.Context) ==
1207 SIF_None) {
1208 unsigned DK =
1209 ExtraInitsIsError
1210 ? diag::err_excess_initializers_in_char_array_initializer
1211 : diag::ext_excess_initializers_in_char_array_initializer;
1212 SemaRef.Diag(IList->getInit(Index)->getBeginLoc(), DK)
1213 << IList->getInit(Index)->getSourceRange();
1214 } else if (T->isSizelessBuiltinType()) {
1215 unsigned DK = ExtraInitsIsError
1216 ? diag::err_excess_initializers_for_sizeless_type
1217 : diag::ext_excess_initializers_for_sizeless_type;
1218 SemaRef.Diag(IList->getInit(Index)->getBeginLoc(), DK)
1219 << T << IList->getInit(Index)->getSourceRange();
1220 } else {
1221 int initKind = T->isArrayType() ? 0 :
1222 T->isVectorType() ? 1 :
1223 T->isScalarType() ? 2 :
1224 T->isUnionType() ? 3 :
1225 4;
1226
1227 unsigned DK = ExtraInitsIsError ? diag::err_excess_initializers
1228 : diag::ext_excess_initializers;
1229 SemaRef.Diag(IList->getInit(Index)->getBeginLoc(), DK)
1230 << initKind << IList->getInit(Index)->getSourceRange();
1231 }
1232 }
1233
1234 if (!VerifyOnly) {
1235 if (T->isScalarType() && IList->getNumInits() == 1 &&
1236 !isa<InitListExpr>(IList->getInit(0)))
1237 warnBracedScalarInit(SemaRef, Entity, IList->getSourceRange());
1238
1239 // Warn if this is a class type that won't be an aggregate in future
1240 // versions of C++.
1241 auto *CXXRD = T->getAsCXXRecordDecl();
1242 if (CXXRD && CXXRD->hasUserDeclaredConstructor()) {
1243 // Don't warn if there's an equivalent default constructor that would be
1244 // used instead.
1245 bool HasEquivCtor = false;
1246 if (IList->getNumInits() == 0) {
1247 auto *CD = SemaRef.LookupDefaultConstructor(CXXRD);
1248 HasEquivCtor = CD && !CD->isDeleted();
1249 }
1250
1251 if (!HasEquivCtor) {
1252 SemaRef.Diag(IList->getBeginLoc(),
1253 diag::warn_cxx20_compat_aggregate_init_with_ctors)
1254 << IList->getSourceRange() << T;
1255 }
1256 }
1257 }
1258}
1259
1260void InitListChecker::CheckListElementTypes(const InitializedEntity &Entity,
1261 InitListExpr *IList,
1262 QualType &DeclType,
1263 bool SubobjectIsDesignatorContext,
1264 unsigned &Index,
1265 InitListExpr *StructuredList,
1266 unsigned &StructuredIndex,
1267 bool TopLevelObject) {
1268 if (DeclType->isAnyComplexType() && SubobjectIsDesignatorContext) {
1269 // Explicitly braced initializer for complex type can be real+imaginary
1270 // parts.
1271 CheckComplexType(Entity, IList, DeclType, Index,
1272 StructuredList, StructuredIndex);
1273 } else if (DeclType->isScalarType()) {
1274 CheckScalarType(Entity, IList, DeclType, Index,
1275 StructuredList, StructuredIndex);
1276 } else if (DeclType->isVectorType()) {
1277 CheckVectorType(Entity, IList, DeclType, Index,
1278 StructuredList, StructuredIndex);
1279 } else if (DeclType->isRecordType()) {
1280 assert(DeclType->isAggregateType() &&((DeclType->isAggregateType() && "non-aggregate records should be handed in CheckSubElementType"
) ? static_cast<void> (0) : __assert_fail ("DeclType->isAggregateType() && \"non-aggregate records should be handed in CheckSubElementType\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1281, __PRETTY_FUNCTION__))
1281 "non-aggregate records should be handed in CheckSubElementType")((DeclType->isAggregateType() && "non-aggregate records should be handed in CheckSubElementType"
) ? static_cast<void> (0) : __assert_fail ("DeclType->isAggregateType() && \"non-aggregate records should be handed in CheckSubElementType\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1281, __PRETTY_FUNCTION__))
;
1282 RecordDecl *RD = DeclType->castAs<RecordType>()->getDecl();
1283 auto Bases =
1284 CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
1285 CXXRecordDecl::base_class_iterator());
1286 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD))
1287 Bases = CXXRD->bases();
1288 CheckStructUnionTypes(Entity, IList, DeclType, Bases, RD->field_begin(),
1289 SubobjectIsDesignatorContext, Index, StructuredList,
1290 StructuredIndex, TopLevelObject);
1291 } else if (DeclType->isArrayType()) {
1292 llvm::APSInt Zero(
1293 SemaRef.Context.getTypeSize(SemaRef.Context.getSizeType()),
1294 false);
1295 CheckArrayType(Entity, IList, DeclType, Zero,
1296 SubobjectIsDesignatorContext, Index,
1297 StructuredList, StructuredIndex);
1298 } else if (DeclType->isVoidType() || DeclType->isFunctionType()) {
1299 // This type is invalid, issue a diagnostic.
1300 ++Index;
1301 if (!VerifyOnly)
1302 SemaRef.Diag(IList->getBeginLoc(), diag::err_illegal_initializer_type)
1303 << DeclType;
1304 hadError = true;
1305 } else if (DeclType->isReferenceType()) {
1306 CheckReferenceType(Entity, IList, DeclType, Index,
1307 StructuredList, StructuredIndex);
1308 } else if (DeclType->isObjCObjectType()) {
1309 if (!VerifyOnly)
1310 SemaRef.Diag(IList->getBeginLoc(), diag::err_init_objc_class) << DeclType;
1311 hadError = true;
1312 } else if (DeclType->isOCLIntelSubgroupAVCType() ||
1313 DeclType->isSizelessBuiltinType()) {
1314 // Checks for scalar type are sufficient for these types too.
1315 CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
1316 StructuredIndex);
1317 } else {
1318 if (!VerifyOnly)
1319 SemaRef.Diag(IList->getBeginLoc(), diag::err_illegal_initializer_type)
1320 << DeclType;
1321 hadError = true;
1322 }
1323}
1324
1325void InitListChecker::CheckSubElementType(const InitializedEntity &Entity,
1326 InitListExpr *IList,
1327 QualType ElemType,
1328 unsigned &Index,
1329 InitListExpr *StructuredList,
1330 unsigned &StructuredIndex,
1331 bool DirectlyDesignated) {
1332 Expr *expr = IList->getInit(Index);
1333
1334 if (ElemType->isReferenceType())
1335 return CheckReferenceType(Entity, IList, ElemType, Index,
1336 StructuredList, StructuredIndex);
1337
1338 if (InitListExpr *SubInitList = dyn_cast<InitListExpr>(expr)) {
1339 if (SubInitList->getNumInits() == 1 &&
1340 IsStringInit(SubInitList->getInit(0), ElemType, SemaRef.Context) ==
1341 SIF_None) {
1342 // FIXME: It would be more faithful and no less correct to include an
1343 // InitListExpr in the semantic form of the initializer list in this case.
1344 expr = SubInitList->getInit(0);
1345 }
1346 // Nested aggregate initialization and C++ initialization are handled later.
1347 } else if (isa<ImplicitValueInitExpr>(expr)) {
1348 // This happens during template instantiation when we see an InitListExpr
1349 // that we've already checked once.
1350 assert(SemaRef.Context.hasSameType(expr->getType(), ElemType) &&((SemaRef.Context.hasSameType(expr->getType(), ElemType) &&
"found implicit initialization for the wrong type") ? static_cast
<void> (0) : __assert_fail ("SemaRef.Context.hasSameType(expr->getType(), ElemType) && \"found implicit initialization for the wrong type\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1351, __PRETTY_FUNCTION__))
1351 "found implicit initialization for the wrong type")((SemaRef.Context.hasSameType(expr->getType(), ElemType) &&
"found implicit initialization for the wrong type") ? static_cast
<void> (0) : __assert_fail ("SemaRef.Context.hasSameType(expr->getType(), ElemType) && \"found implicit initialization for the wrong type\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1351, __PRETTY_FUNCTION__))
;
1352 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1353 ++Index;
1354 return;
1355 }
1356
1357 if (SemaRef.getLangOpts().CPlusPlus || isa<InitListExpr>(expr)) {
1358 // C++ [dcl.init.aggr]p2:
1359 // Each member is copy-initialized from the corresponding
1360 // initializer-clause.
1361
1362 // FIXME: Better EqualLoc?
1363 InitializationKind Kind =
1364 InitializationKind::CreateCopy(expr->getBeginLoc(), SourceLocation());
1365
1366 // Vector elements can be initialized from other vectors in which case
1367 // we need initialization entity with a type of a vector (and not a vector
1368 // element!) initializing multiple vector elements.
1369 auto TmpEntity =
1370 (ElemType->isExtVectorType() && !Entity.getType()->isExtVectorType())
1371 ? InitializedEntity::InitializeTemporary(ElemType)
1372 : Entity;
1373
1374 InitializationSequence Seq(SemaRef, TmpEntity, Kind, expr,
1375 /*TopLevelOfInitList*/ true);
1376
1377 // C++14 [dcl.init.aggr]p13:
1378 // If the assignment-expression can initialize a member, the member is
1379 // initialized. Otherwise [...] brace elision is assumed
1380 //
1381 // Brace elision is never performed if the element is not an
1382 // assignment-expression.
1383 if (Seq || isa<InitListExpr>(expr)) {
1384 if (!VerifyOnly) {
1385 ExprResult Result = Seq.Perform(SemaRef, TmpEntity, Kind, expr);
1386 if (Result.isInvalid())
1387 hadError = true;
1388
1389 UpdateStructuredListElement(StructuredList, StructuredIndex,
1390 Result.getAs<Expr>());
1391 } else if (!Seq) {
1392 hadError = true;
1393 } else if (StructuredList) {
1394 UpdateStructuredListElement(StructuredList, StructuredIndex,
1395 getDummyInit());
1396 }
1397 ++Index;
1398 return;
1399 }
1400
1401 // Fall through for subaggregate initialization
1402 } else if (ElemType->isScalarType() || ElemType->isAtomicType()) {
1403 // FIXME: Need to handle atomic aggregate types with implicit init lists.
1404 return CheckScalarType(Entity, IList, ElemType, Index,
1405 StructuredList, StructuredIndex);
1406 } else if (const ArrayType *arrayType =
1407 SemaRef.Context.getAsArrayType(ElemType)) {
1408 // arrayType can be incomplete if we're initializing a flexible
1409 // array member. There's nothing we can do with the completed
1410 // type here, though.
1411
1412 if (IsStringInit(expr, arrayType, SemaRef.Context) == SIF_None) {
1413 // FIXME: Should we do this checking in verify-only mode?
1414 if (!VerifyOnly)
1415 CheckStringInit(expr, ElemType, arrayType, SemaRef);
1416 if (StructuredList)
1417 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1418 ++Index;
1419 return;
1420 }
1421
1422 // Fall through for subaggregate initialization.
1423
1424 } else {
1425 assert((ElemType->isRecordType() || ElemType->isVectorType() ||(((ElemType->isRecordType() || ElemType->isVectorType()
|| ElemType->isOpenCLSpecificType()) && "Unexpected type"
) ? static_cast<void> (0) : __assert_fail ("(ElemType->isRecordType() || ElemType->isVectorType() || ElemType->isOpenCLSpecificType()) && \"Unexpected type\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1426, __PRETTY_FUNCTION__))
1426 ElemType->isOpenCLSpecificType()) && "Unexpected type")(((ElemType->isRecordType() || ElemType->isVectorType()
|| ElemType->isOpenCLSpecificType()) && "Unexpected type"
) ? static_cast<void> (0) : __assert_fail ("(ElemType->isRecordType() || ElemType->isVectorType() || ElemType->isOpenCLSpecificType()) && \"Unexpected type\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1426, __PRETTY_FUNCTION__))
;
1427
1428 // C99 6.7.8p13:
1429 //
1430 // The initializer for a structure or union object that has
1431 // automatic storage duration shall be either an initializer
1432 // list as described below, or a single expression that has
1433 // compatible structure or union type. In the latter case, the
1434 // initial value of the object, including unnamed members, is
1435 // that of the expression.
1436 ExprResult ExprRes = expr;
1437 if (SemaRef.CheckSingleAssignmentConstraints(
1438 ElemType, ExprRes, !VerifyOnly) != Sema::Incompatible) {
1439 if (ExprRes.isInvalid())
1440 hadError = true;
1441 else {
1442 ExprRes = SemaRef.DefaultFunctionArrayLvalueConversion(ExprRes.get());
1443 if (ExprRes.isInvalid())
1444 hadError = true;
1445 }
1446 UpdateStructuredListElement(StructuredList, StructuredIndex,
1447 ExprRes.getAs<Expr>());
1448 ++Index;
1449 return;
1450 }
1451 ExprRes.get();
1452 // Fall through for subaggregate initialization
1453 }
1454
1455 // C++ [dcl.init.aggr]p12:
1456 //
1457 // [...] Otherwise, if the member is itself a non-empty
1458 // subaggregate, brace elision is assumed and the initializer is
1459 // considered for the initialization of the first member of
1460 // the subaggregate.
1461 // OpenCL vector initializer is handled elsewhere.
1462 if ((!SemaRef.getLangOpts().OpenCL && ElemType->isVectorType()) ||
1463 ElemType->isAggregateType()) {
1464 CheckImplicitInitList(Entity, IList, ElemType, Index, StructuredList,
1465 StructuredIndex);
1466 ++StructuredIndex;
1467
1468 // In C++20, brace elision is not permitted for a designated initializer.
1469 if (DirectlyDesignated && SemaRef.getLangOpts().CPlusPlus && !hadError) {
1470 if (InOverloadResolution)
1471 hadError = true;
1472 if (!VerifyOnly) {
1473 SemaRef.Diag(expr->getBeginLoc(),
1474 diag::ext_designated_init_brace_elision)
1475 << expr->getSourceRange()
1476 << FixItHint::CreateInsertion(expr->getBeginLoc(), "{")
1477 << FixItHint::CreateInsertion(
1478 SemaRef.getLocForEndOfToken(expr->getEndLoc()), "}");
1479 }
1480 }
1481 } else {
1482 if (!VerifyOnly) {
1483 // We cannot initialize this element, so let PerformCopyInitialization
1484 // produce the appropriate diagnostic. We already checked that this
1485 // initialization will fail.
1486 ExprResult Copy =
1487 SemaRef.PerformCopyInitialization(Entity, SourceLocation(), expr,
1488 /*TopLevelOfInitList=*/true);
1489 (void)Copy;
1490 assert(Copy.isInvalid() &&((Copy.isInvalid() && "expected non-aggregate initialization to fail"
) ? static_cast<void> (0) : __assert_fail ("Copy.isInvalid() && \"expected non-aggregate initialization to fail\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1491, __PRETTY_FUNCTION__))
1491 "expected non-aggregate initialization to fail")((Copy.isInvalid() && "expected non-aggregate initialization to fail"
) ? static_cast<void> (0) : __assert_fail ("Copy.isInvalid() && \"expected non-aggregate initialization to fail\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1491, __PRETTY_FUNCTION__))
;
1492 }
1493 hadError = true;
1494 ++Index;
1495 ++StructuredIndex;
1496 }
1497}
1498
1499void InitListChecker::CheckComplexType(const InitializedEntity &Entity,
1500 InitListExpr *IList, QualType DeclType,
1501 unsigned &Index,
1502 InitListExpr *StructuredList,
1503 unsigned &StructuredIndex) {
1504 assert(Index == 0 && "Index in explicit init list must be zero")((Index == 0 && "Index in explicit init list must be zero"
) ? static_cast<void> (0) : __assert_fail ("Index == 0 && \"Index in explicit init list must be zero\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1504, __PRETTY_FUNCTION__))
;
1505
1506 // As an extension, clang supports complex initializers, which initialize
1507 // a complex number component-wise. When an explicit initializer list for
1508 // a complex number contains two two initializers, this extension kicks in:
1509 // it exepcts the initializer list to contain two elements convertible to
1510 // the element type of the complex type. The first element initializes
1511 // the real part, and the second element intitializes the imaginary part.
1512
1513 if (IList->getNumInits() != 2)
1514 return CheckScalarType(Entity, IList, DeclType, Index, StructuredList,
1515 StructuredIndex);
1516
1517 // This is an extension in C. (The builtin _Complex type does not exist
1518 // in the C++ standard.)
1519 if (!SemaRef.getLangOpts().CPlusPlus && !VerifyOnly)
1520 SemaRef.Diag(IList->getBeginLoc(), diag::ext_complex_component_init)
1521 << IList->getSourceRange();
1522
1523 // Initialize the complex number.
1524 QualType elementType = DeclType->castAs<ComplexType>()->getElementType();
1525 InitializedEntity ElementEntity =
1526 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1527
1528 for (unsigned i = 0; i < 2; ++i) {
1529 ElementEntity.setElementIndex(Index);
1530 CheckSubElementType(ElementEntity, IList, elementType, Index,
1531 StructuredList, StructuredIndex);
1532 }
1533}
1534
1535void InitListChecker::CheckScalarType(const InitializedEntity &Entity,
1536 InitListExpr *IList, QualType DeclType,
1537 unsigned &Index,
1538 InitListExpr *StructuredList,
1539 unsigned &StructuredIndex) {
1540 if (Index >= IList->getNumInits()) {
1541 if (!VerifyOnly) {
1542 if (DeclType->isSizelessBuiltinType())
1543 SemaRef.Diag(IList->getBeginLoc(),
1544 SemaRef.getLangOpts().CPlusPlus11
1545 ? diag::warn_cxx98_compat_empty_sizeless_initializer
1546 : diag::err_empty_sizeless_initializer)
1547 << DeclType << IList->getSourceRange();
1548 else
1549 SemaRef.Diag(IList->getBeginLoc(),
1550 SemaRef.getLangOpts().CPlusPlus11
1551 ? diag::warn_cxx98_compat_empty_scalar_initializer
1552 : diag::err_empty_scalar_initializer)
1553 << IList->getSourceRange();
1554 }
1555 hadError = !SemaRef.getLangOpts().CPlusPlus11;
1556 ++Index;
1557 ++StructuredIndex;
1558 return;
1559 }
1560
1561 Expr *expr = IList->getInit(Index);
1562 if (InitListExpr *SubIList = dyn_cast<InitListExpr>(expr)) {
1563 // FIXME: This is invalid, and accepting it causes overload resolution
1564 // to pick the wrong overload in some corner cases.
1565 if (!VerifyOnly)
1566 SemaRef.Diag(SubIList->getBeginLoc(), diag::ext_many_braces_around_init)
1567 << DeclType->isSizelessBuiltinType() << SubIList->getSourceRange();
1568
1569 CheckScalarType(Entity, SubIList, DeclType, Index, StructuredList,
1570 StructuredIndex);
1571 return;
1572 } else if (isa<DesignatedInitExpr>(expr)) {
1573 if (!VerifyOnly)
1574 SemaRef.Diag(expr->getBeginLoc(),
1575 diag::err_designator_for_scalar_or_sizeless_init)
1576 << DeclType->isSizelessBuiltinType() << DeclType
1577 << expr->getSourceRange();
1578 hadError = true;
1579 ++Index;
1580 ++StructuredIndex;
1581 return;
1582 }
1583
1584 ExprResult Result;
1585 if (VerifyOnly) {
1586 if (SemaRef.CanPerformCopyInitialization(Entity, expr))
1587 Result = getDummyInit();
1588 else
1589 Result = ExprError();
1590 } else {
1591 Result =
1592 SemaRef.PerformCopyInitialization(Entity, expr->getBeginLoc(), expr,
1593 /*TopLevelOfInitList=*/true);
1594 }
1595
1596 Expr *ResultExpr = nullptr;
1597
1598 if (Result.isInvalid())
1599 hadError = true; // types weren't compatible.
1600 else {
1601 ResultExpr = Result.getAs<Expr>();
1602
1603 if (ResultExpr != expr && !VerifyOnly) {
1604 // The type was promoted, update initializer list.
1605 // FIXME: Why are we updating the syntactic init list?
1606 IList->setInit(Index, ResultExpr);
1607 }
1608 }
1609 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr);
1610 ++Index;
1611}
1612
1613void InitListChecker::CheckReferenceType(const InitializedEntity &Entity,
1614 InitListExpr *IList, QualType DeclType,
1615 unsigned &Index,
1616 InitListExpr *StructuredList,
1617 unsigned &StructuredIndex) {
1618 if (Index >= IList->getNumInits()) {
1619 // FIXME: It would be wonderful if we could point at the actual member. In
1620 // general, it would be useful to pass location information down the stack,
1621 // so that we know the location (or decl) of the "current object" being
1622 // initialized.
1623 if (!VerifyOnly)
1624 SemaRef.Diag(IList->getBeginLoc(),
1625 diag::err_init_reference_member_uninitialized)
1626 << DeclType << IList->getSourceRange();
1627 hadError = true;
1628 ++Index;
1629 ++StructuredIndex;
1630 return;
1631 }
1632
1633 Expr *expr = IList->getInit(Index);
1634 if (isa<InitListExpr>(expr) && !SemaRef.getLangOpts().CPlusPlus11) {
1635 if (!VerifyOnly)
1636 SemaRef.Diag(IList->getBeginLoc(), diag::err_init_non_aggr_init_list)
1637 << DeclType << IList->getSourceRange();
1638 hadError = true;
1639 ++Index;
1640 ++StructuredIndex;
1641 return;
1642 }
1643
1644 ExprResult Result;
1645 if (VerifyOnly) {
1646 if (SemaRef.CanPerformCopyInitialization(Entity,expr))
1647 Result = getDummyInit();
1648 else
1649 Result = ExprError();
1650 } else {
1651 Result =
1652 SemaRef.PerformCopyInitialization(Entity, expr->getBeginLoc(), expr,
1653 /*TopLevelOfInitList=*/true);
1654 }
1655
1656 if (Result.isInvalid())
1657 hadError = true;
1658
1659 expr = Result.getAs<Expr>();
1660 // FIXME: Why are we updating the syntactic init list?
1661 if (!VerifyOnly && expr)
1662 IList->setInit(Index, expr);
1663
1664 UpdateStructuredListElement(StructuredList, StructuredIndex, expr);
1665 ++Index;
1666}
1667
1668void InitListChecker::CheckVectorType(const InitializedEntity &Entity,
1669 InitListExpr *IList, QualType DeclType,
1670 unsigned &Index,
1671 InitListExpr *StructuredList,
1672 unsigned &StructuredIndex) {
1673 const VectorType *VT = DeclType->castAs<VectorType>();
1674 unsigned maxElements = VT->getNumElements();
1675 unsigned numEltsInit = 0;
1676 QualType elementType = VT->getElementType();
1677
1678 if (Index >= IList->getNumInits()) {
1679 // Make sure the element type can be value-initialized.
1680 CheckEmptyInitializable(
1681 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
1682 IList->getEndLoc());
1683 return;
1684 }
1685
1686 if (!SemaRef.getLangOpts().OpenCL) {
1687 // If the initializing element is a vector, try to copy-initialize
1688 // instead of breaking it apart (which is doomed to failure anyway).
1689 Expr *Init = IList->getInit(Index);
1690 if (!isa<InitListExpr>(Init) && Init->getType()->isVectorType()) {
1691 ExprResult Result;
1692 if (VerifyOnly) {
1693 if (SemaRef.CanPerformCopyInitialization(Entity, Init))
1694 Result = getDummyInit();
1695 else
1696 Result = ExprError();
1697 } else {
1698 Result =
1699 SemaRef.PerformCopyInitialization(Entity, Init->getBeginLoc(), Init,
1700 /*TopLevelOfInitList=*/true);
1701 }
1702
1703 Expr *ResultExpr = nullptr;
1704 if (Result.isInvalid())
1705 hadError = true; // types weren't compatible.
1706 else {
1707 ResultExpr = Result.getAs<Expr>();
1708
1709 if (ResultExpr != Init && !VerifyOnly) {
1710 // The type was promoted, update initializer list.
1711 // FIXME: Why are we updating the syntactic init list?
1712 IList->setInit(Index, ResultExpr);
1713 }
1714 }
1715 UpdateStructuredListElement(StructuredList, StructuredIndex, ResultExpr);
1716 ++Index;
1717 return;
1718 }
1719
1720 InitializedEntity ElementEntity =
1721 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1722
1723 for (unsigned i = 0; i < maxElements; ++i, ++numEltsInit) {
1724 // Don't attempt to go past the end of the init list
1725 if (Index >= IList->getNumInits()) {
1726 CheckEmptyInitializable(ElementEntity, IList->getEndLoc());
1727 break;
1728 }
1729
1730 ElementEntity.setElementIndex(Index);
1731 CheckSubElementType(ElementEntity, IList, elementType, Index,
1732 StructuredList, StructuredIndex);
1733 }
1734
1735 if (VerifyOnly)
1736 return;
1737
1738 bool isBigEndian = SemaRef.Context.getTargetInfo().isBigEndian();
1739 const VectorType *T = Entity.getType()->castAs<VectorType>();
1740 if (isBigEndian && (T->getVectorKind() == VectorType::NeonVector ||
1741 T->getVectorKind() == VectorType::NeonPolyVector)) {
1742 // The ability to use vector initializer lists is a GNU vector extension
1743 // and is unrelated to the NEON intrinsics in arm_neon.h. On little
1744 // endian machines it works fine, however on big endian machines it
1745 // exhibits surprising behaviour:
1746 //
1747 // uint32x2_t x = {42, 64};
1748 // return vget_lane_u32(x, 0); // Will return 64.
1749 //
1750 // Because of this, explicitly call out that it is non-portable.
1751 //
1752 SemaRef.Diag(IList->getBeginLoc(),
1753 diag::warn_neon_vector_initializer_non_portable);
1754
1755 const char *typeCode;
1756 unsigned typeSize = SemaRef.Context.getTypeSize(elementType);
1757
1758 if (elementType->isFloatingType())
1759 typeCode = "f";
1760 else if (elementType->isSignedIntegerType())
1761 typeCode = "s";
1762 else if (elementType->isUnsignedIntegerType())
1763 typeCode = "u";
1764 else
1765 llvm_unreachable("Invalid element type!")::llvm::llvm_unreachable_internal("Invalid element type!", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 1765)
;
1766
1767 SemaRef.Diag(IList->getBeginLoc(),
1768 SemaRef.Context.getTypeSize(VT) > 64
1769 ? diag::note_neon_vector_initializer_non_portable_q
1770 : diag::note_neon_vector_initializer_non_portable)
1771 << typeCode << typeSize;
1772 }
1773
1774 return;
1775 }
1776
1777 InitializedEntity ElementEntity =
1778 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
1779
1780 // OpenCL initializers allows vectors to be constructed from vectors.
1781 for (unsigned i = 0; i < maxElements; ++i) {
1782 // Don't attempt to go past the end of the init list
1783 if (Index >= IList->getNumInits())
1784 break;
1785
1786 ElementEntity.setElementIndex(Index);
1787
1788 QualType IType = IList->getInit(Index)->getType();
1789 if (!IType->isVectorType()) {
1790 CheckSubElementType(ElementEntity, IList, elementType, Index,
1791 StructuredList, StructuredIndex);
1792 ++numEltsInit;
1793 } else {
1794 QualType VecType;
1795 const VectorType *IVT = IType->castAs<VectorType>();
1796 unsigned numIElts = IVT->getNumElements();
1797
1798 if (IType->isExtVectorType())
1799 VecType = SemaRef.Context.getExtVectorType(elementType, numIElts);
1800 else
1801 VecType = SemaRef.Context.getVectorType(elementType, numIElts,
1802 IVT->getVectorKind());
1803 CheckSubElementType(ElementEntity, IList, VecType, Index,
1804 StructuredList, StructuredIndex);
1805 numEltsInit += numIElts;
1806 }
1807 }
1808
1809 // OpenCL requires all elements to be initialized.
1810 if (numEltsInit != maxElements) {
1811 if (!VerifyOnly)
1812 SemaRef.Diag(IList->getBeginLoc(),
1813 diag::err_vector_incorrect_num_initializers)
1814 << (numEltsInit < maxElements) << maxElements << numEltsInit;
1815 hadError = true;
1816 }
1817}
1818
1819/// Check if the type of a class element has an accessible destructor, and marks
1820/// it referenced. Returns true if we shouldn't form a reference to the
1821/// destructor.
1822///
1823/// Aggregate initialization requires a class element's destructor be
1824/// accessible per 11.6.1 [dcl.init.aggr]:
1825///
1826/// The destructor for each element of class type is potentially invoked
1827/// (15.4 [class.dtor]) from the context where the aggregate initialization
1828/// occurs.
1829static bool checkDestructorReference(QualType ElementType, SourceLocation Loc,
1830 Sema &SemaRef) {
1831 auto *CXXRD = ElementType->getAsCXXRecordDecl();
1832 if (!CXXRD)
1833 return false;
1834
1835 CXXDestructorDecl *Destructor = SemaRef.LookupDestructor(CXXRD);
1836 SemaRef.CheckDestructorAccess(Loc, Destructor,
1837 SemaRef.PDiag(diag::err_access_dtor_temp)
1838 << ElementType);
1839 SemaRef.MarkFunctionReferenced(Loc, Destructor);
1840 return SemaRef.DiagnoseUseOfDecl(Destructor, Loc);
1841}
1842
1843void InitListChecker::CheckArrayType(const InitializedEntity &Entity,
1844 InitListExpr *IList, QualType &DeclType,
1845 llvm::APSInt elementIndex,
1846 bool SubobjectIsDesignatorContext,
1847 unsigned &Index,
1848 InitListExpr *StructuredList,
1849 unsigned &StructuredIndex) {
1850 const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType);
1851
1852 if (!VerifyOnly) {
1853 if (checkDestructorReference(arrayType->getElementType(),
1854 IList->getEndLoc(), SemaRef)) {
1855 hadError = true;
1856 return;
1857 }
1858 }
1859
1860 // Check for the special-case of initializing an array with a string.
1861 if (Index < IList->getNumInits()) {
1862 if (IsStringInit(IList->getInit(Index), arrayType, SemaRef.Context) ==
1863 SIF_None) {
1864 // We place the string literal directly into the resulting
1865 // initializer list. This is the only place where the structure
1866 // of the structured initializer list doesn't match exactly,
1867 // because doing so would involve allocating one character
1868 // constant for each string.
1869 // FIXME: Should we do these checks in verify-only mode too?
1870 if (!VerifyOnly)
1871 CheckStringInit(IList->getInit(Index), DeclType, arrayType, SemaRef);
1872 if (StructuredList) {
1873 UpdateStructuredListElement(StructuredList, StructuredIndex,
1874 IList->getInit(Index));
1875 StructuredList->resizeInits(SemaRef.Context, StructuredIndex);
1876 }
1877 ++Index;
1878 return;
1879 }
1880 }
1881 if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(arrayType)) {
1882 // Check for VLAs; in standard C it would be possible to check this
1883 // earlier, but I don't know where clang accepts VLAs (gcc accepts
1884 // them in all sorts of strange places).
1885 if (!VerifyOnly)
1886 SemaRef.Diag(VAT->getSizeExpr()->getBeginLoc(),
1887 diag::err_variable_object_no_init)
1888 << VAT->getSizeExpr()->getSourceRange();
1889 hadError = true;
1890 ++Index;
1891 ++StructuredIndex;
1892 return;
1893 }
1894
1895 // We might know the maximum number of elements in advance.
1896 llvm::APSInt maxElements(elementIndex.getBitWidth(),
1897 elementIndex.isUnsigned());
1898 bool maxElementsKnown = false;
1899 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(arrayType)) {
1900 maxElements = CAT->getSize();
1901 elementIndex = elementIndex.extOrTrunc(maxElements.getBitWidth());
1902 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1903 maxElementsKnown = true;
1904 }
1905
1906 QualType elementType = arrayType->getElementType();
1907 while (Index < IList->getNumInits()) {
1908 Expr *Init = IList->getInit(Index);
1909 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
1910 // If we're not the subobject that matches up with the '{' for
1911 // the designator, we shouldn't be handling the
1912 // designator. Return immediately.
1913 if (!SubobjectIsDesignatorContext)
1914 return;
1915
1916 // Handle this designated initializer. elementIndex will be
1917 // updated to be the next array element we'll initialize.
1918 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
1919 DeclType, nullptr, &elementIndex, Index,
1920 StructuredList, StructuredIndex, true,
1921 false)) {
1922 hadError = true;
1923 continue;
1924 }
1925
1926 if (elementIndex.getBitWidth() > maxElements.getBitWidth())
1927 maxElements = maxElements.extend(elementIndex.getBitWidth());
1928 else if (elementIndex.getBitWidth() < maxElements.getBitWidth())
1929 elementIndex = elementIndex.extend(maxElements.getBitWidth());
1930 elementIndex.setIsUnsigned(maxElements.isUnsigned());
1931
1932 // If the array is of incomplete type, keep track of the number of
1933 // elements in the initializer.
1934 if (!maxElementsKnown && elementIndex > maxElements)
1935 maxElements = elementIndex;
1936
1937 continue;
1938 }
1939
1940 // If we know the maximum number of elements, and we've already
1941 // hit it, stop consuming elements in the initializer list.
1942 if (maxElementsKnown && elementIndex == maxElements)
1943 break;
1944
1945 InitializedEntity ElementEntity =
1946 InitializedEntity::InitializeElement(SemaRef.Context, StructuredIndex,
1947 Entity);
1948 // Check this element.
1949 CheckSubElementType(ElementEntity, IList, elementType, Index,
1950 StructuredList, StructuredIndex);
1951 ++elementIndex;
1952
1953 // If the array is of incomplete type, keep track of the number of
1954 // elements in the initializer.
1955 if (!maxElementsKnown && elementIndex > maxElements)
1956 maxElements = elementIndex;
1957 }
1958 if (!hadError && DeclType->isIncompleteArrayType() && !VerifyOnly) {
1959 // If this is an incomplete array type, the actual type needs to
1960 // be calculated here.
1961 llvm::APSInt Zero(maxElements.getBitWidth(), maxElements.isUnsigned());
1962 if (maxElements == Zero && !Entity.isVariableLengthArrayNew()) {
1963 // Sizing an array implicitly to zero is not allowed by ISO C,
1964 // but is supported by GNU.
1965 SemaRef.Diag(IList->getBeginLoc(), diag::ext_typecheck_zero_array_size);
1966 }
1967
1968 DeclType = SemaRef.Context.getConstantArrayType(
1969 elementType, maxElements, nullptr, ArrayType::Normal, 0);
1970 }
1971 if (!hadError) {
1972 // If there are any members of the array that get value-initialized, check
1973 // that is possible. That happens if we know the bound and don't have
1974 // enough elements, or if we're performing an array new with an unknown
1975 // bound.
1976 if ((maxElementsKnown && elementIndex < maxElements) ||
1977 Entity.isVariableLengthArrayNew())
1978 CheckEmptyInitializable(
1979 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity),
1980 IList->getEndLoc());
1981 }
1982}
1983
1984bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity,
1985 Expr *InitExpr,
1986 FieldDecl *Field,
1987 bool TopLevelObject) {
1988 // Handle GNU flexible array initializers.
1989 unsigned FlexArrayDiag;
1990 if (isa<InitListExpr>(InitExpr) &&
1991 cast<InitListExpr>(InitExpr)->getNumInits() == 0) {
1992 // Empty flexible array init always allowed as an extension
1993 FlexArrayDiag = diag::ext_flexible_array_init;
1994 } else if (SemaRef.getLangOpts().CPlusPlus) {
1995 // Disallow flexible array init in C++; it is not required for gcc
1996 // compatibility, and it needs work to IRGen correctly in general.
1997 FlexArrayDiag = diag::err_flexible_array_init;
1998 } else if (!TopLevelObject) {
1999 // Disallow flexible array init on non-top-level object
2000 FlexArrayDiag = diag::err_flexible_array_init;
2001 } else if (Entity.getKind() != InitializedEntity::EK_Variable) {
2002 // Disallow flexible array init on anything which is not a variable.
2003 FlexArrayDiag = diag::err_flexible_array_init;
2004 } else if (cast<VarDecl>(Entity.getDecl())->hasLocalStorage()) {
2005 // Disallow flexible array init on local variables.
2006 FlexArrayDiag = diag::err_flexible_array_init;
2007 } else {
2008 // Allow other cases.
2009 FlexArrayDiag = diag::ext_flexible_array_init;
2010 }
2011
2012 if (!VerifyOnly) {
2013 SemaRef.Diag(InitExpr->getBeginLoc(), FlexArrayDiag)
2014 << InitExpr->getBeginLoc();
2015 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2016 << Field;
2017 }
2018
2019 return FlexArrayDiag != diag::ext_flexible_array_init;
2020}
2021
2022void InitListChecker::CheckStructUnionTypes(
2023 const InitializedEntity &Entity, InitListExpr *IList, QualType DeclType,
2024 CXXRecordDecl::base_class_range Bases, RecordDecl::field_iterator Field,
2025 bool SubobjectIsDesignatorContext, unsigned &Index,
2026 InitListExpr *StructuredList, unsigned &StructuredIndex,
2027 bool TopLevelObject) {
2028 RecordDecl *structDecl = DeclType->castAs<RecordType>()->getDecl();
2029
2030 // If the record is invalid, some of it's members are invalid. To avoid
2031 // confusion, we forgo checking the intializer for the entire record.
2032 if (structDecl->isInvalidDecl()) {
2033 // Assume it was supposed to consume a single initializer.
2034 ++Index;
2035 hadError = true;
2036 return;
2037 }
2038
2039 if (DeclType->isUnionType() && IList->getNumInits() == 0) {
2040 RecordDecl *RD = DeclType->castAs<RecordType>()->getDecl();
2041
2042 if (!VerifyOnly)
2043 for (FieldDecl *FD : RD->fields()) {
2044 QualType ET = SemaRef.Context.getBaseElementType(FD->getType());
2045 if (checkDestructorReference(ET, IList->getEndLoc(), SemaRef)) {
2046 hadError = true;
2047 return;
2048 }
2049 }
2050
2051 // If there's a default initializer, use it.
2052 if (isa<CXXRecordDecl>(RD) &&
2053 cast<CXXRecordDecl>(RD)->hasInClassInitializer()) {
2054 if (!StructuredList)
2055 return;
2056 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
2057 Field != FieldEnd; ++Field) {
2058 if (Field->hasInClassInitializer()) {
2059 StructuredList->setInitializedFieldInUnion(*Field);
2060 // FIXME: Actually build a CXXDefaultInitExpr?
2061 return;
2062 }
2063 }
2064 }
2065
2066 // Value-initialize the first member of the union that isn't an unnamed
2067 // bitfield.
2068 for (RecordDecl::field_iterator FieldEnd = RD->field_end();
2069 Field != FieldEnd; ++Field) {
2070 if (!Field->isUnnamedBitfield()) {
2071 CheckEmptyInitializable(
2072 InitializedEntity::InitializeMember(*Field, &Entity),
2073 IList->getEndLoc());
2074 if (StructuredList)
2075 StructuredList->setInitializedFieldInUnion(*Field);
2076 break;
2077 }
2078 }
2079 return;
2080 }
2081
2082 bool InitializedSomething = false;
2083
2084 // If we have any base classes, they are initialized prior to the fields.
2085 for (auto &Base : Bases) {
2086 Expr *Init = Index < IList->getNumInits() ? IList->getInit(Index) : nullptr;
2087
2088 // Designated inits always initialize fields, so if we see one, all
2089 // remaining base classes have no explicit initializer.
2090 if (Init && isa<DesignatedInitExpr>(Init))
2091 Init = nullptr;
2092
2093 SourceLocation InitLoc = Init ? Init->getBeginLoc() : IList->getEndLoc();
2094 InitializedEntity BaseEntity = InitializedEntity::InitializeBase(
2095 SemaRef.Context, &Base, false, &Entity);
2096 if (Init) {
2097 CheckSubElementType(BaseEntity, IList, Base.getType(), Index,
2098 StructuredList, StructuredIndex);
2099 InitializedSomething = true;
2100 } else {
2101 CheckEmptyInitializable(BaseEntity, InitLoc);
2102 }
2103
2104 if (!VerifyOnly)
2105 if (checkDestructorReference(Base.getType(), InitLoc, SemaRef)) {
2106 hadError = true;
2107 return;
2108 }
2109 }
2110
2111 // If structDecl is a forward declaration, this loop won't do
2112 // anything except look at designated initializers; That's okay,
2113 // because an error should get printed out elsewhere. It might be
2114 // worthwhile to skip over the rest of the initializer, though.
2115 RecordDecl *RD = DeclType->castAs<RecordType>()->getDecl();
2116 RecordDecl::field_iterator FieldEnd = RD->field_end();
2117 bool CheckForMissingFields =
2118 !IList->isIdiomaticZeroInitializer(SemaRef.getLangOpts());
2119 bool HasDesignatedInit = false;
2120
2121 while (Index < IList->getNumInits()) {
2122 Expr *Init = IList->getInit(Index);
2123 SourceLocation InitLoc = Init->getBeginLoc();
2124
2125 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) {
2126 // If we're not the subobject that matches up with the '{' for
2127 // the designator, we shouldn't be handling the
2128 // designator. Return immediately.
2129 if (!SubobjectIsDesignatorContext)
2130 return;
2131
2132 HasDesignatedInit = true;
2133
2134 // Handle this designated initializer. Field will be updated to
2135 // the next field that we'll be initializing.
2136 if (CheckDesignatedInitializer(Entity, IList, DIE, 0,
2137 DeclType, &Field, nullptr, Index,
2138 StructuredList, StructuredIndex,
2139 true, TopLevelObject))
2140 hadError = true;
2141 else if (!VerifyOnly) {
2142 // Find the field named by the designated initializer.
2143 RecordDecl::field_iterator F = RD->field_begin();
2144 while (std::next(F) != Field)
2145 ++F;
2146 QualType ET = SemaRef.Context.getBaseElementType(F->getType());
2147 if (checkDestructorReference(ET, InitLoc, SemaRef)) {
2148 hadError = true;
2149 return;
2150 }
2151 }
2152
2153 InitializedSomething = true;
2154
2155 // Disable check for missing fields when designators are used.
2156 // This matches gcc behaviour.
2157 CheckForMissingFields = false;
2158 continue;
2159 }
2160
2161 if (Field == FieldEnd) {
2162 // We've run out of fields. We're done.
2163 break;
2164 }
2165
2166 // We've already initialized a member of a union. We're done.
2167 if (InitializedSomething && DeclType->isUnionType())
2168 break;
2169
2170 // If we've hit the flexible array member at the end, we're done.
2171 if (Field->getType()->isIncompleteArrayType())
2172 break;
2173
2174 if (Field->isUnnamedBitfield()) {
2175 // Don't initialize unnamed bitfields, e.g. "int : 20;"
2176 ++Field;
2177 continue;
2178 }
2179
2180 // Make sure we can use this declaration.
2181 bool InvalidUse;
2182 if (VerifyOnly)
2183 InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
2184 else
2185 InvalidUse = SemaRef.DiagnoseUseOfDecl(
2186 *Field, IList->getInit(Index)->getBeginLoc());
2187 if (InvalidUse) {
2188 ++Index;
2189 ++Field;
2190 hadError = true;
2191 continue;
2192 }
2193
2194 if (!VerifyOnly) {
2195 QualType ET = SemaRef.Context.getBaseElementType(Field->getType());
2196 if (checkDestructorReference(ET, InitLoc, SemaRef)) {
2197 hadError = true;
2198 return;
2199 }
2200 }
2201
2202 InitializedEntity MemberEntity =
2203 InitializedEntity::InitializeMember(*Field, &Entity);
2204 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2205 StructuredList, StructuredIndex);
2206 InitializedSomething = true;
2207
2208 if (DeclType->isUnionType() && StructuredList) {
2209 // Initialize the first field within the union.
2210 StructuredList->setInitializedFieldInUnion(*Field);
2211 }
2212
2213 ++Field;
2214 }
2215
2216 // Emit warnings for missing struct field initializers.
2217 if (!VerifyOnly && InitializedSomething && CheckForMissingFields &&
2218 Field != FieldEnd && !Field->getType()->isIncompleteArrayType() &&
2219 !DeclType->isUnionType()) {
2220 // It is possible we have one or more unnamed bitfields remaining.
2221 // Find first (if any) named field and emit warning.
2222 for (RecordDecl::field_iterator it = Field, end = RD->field_end();
2223 it != end; ++it) {
2224 if (!it->isUnnamedBitfield() && !it->hasInClassInitializer()) {
2225 SemaRef.Diag(IList->getSourceRange().getEnd(),
2226 diag::warn_missing_field_initializers) << *it;
2227 break;
2228 }
2229 }
2230 }
2231
2232 // Check that any remaining fields can be value-initialized if we're not
2233 // building a structured list. (If we are, we'll check this later.)
2234 if (!StructuredList && Field != FieldEnd && !DeclType->isUnionType() &&
2235 !Field->getType()->isIncompleteArrayType()) {
2236 for (; Field != FieldEnd && !hadError; ++Field) {
2237 if (!Field->isUnnamedBitfield() && !Field->hasInClassInitializer())
2238 CheckEmptyInitializable(
2239 InitializedEntity::InitializeMember(*Field, &Entity),
2240 IList->getEndLoc());
2241 }
2242 }
2243
2244 // Check that the types of the remaining fields have accessible destructors.
2245 if (!VerifyOnly) {
2246 // If the initializer expression has a designated initializer, check the
2247 // elements for which a designated initializer is not provided too.
2248 RecordDecl::field_iterator I = HasDesignatedInit ? RD->field_begin()
2249 : Field;
2250 for (RecordDecl::field_iterator E = RD->field_end(); I != E; ++I) {
2251 QualType ET = SemaRef.Context.getBaseElementType(I->getType());
2252 if (checkDestructorReference(ET, IList->getEndLoc(), SemaRef)) {
2253 hadError = true;
2254 return;
2255 }
2256 }
2257 }
2258
2259 if (Field == FieldEnd || !Field->getType()->isIncompleteArrayType() ||
2260 Index >= IList->getNumInits())
2261 return;
2262
2263 if (CheckFlexibleArrayInit(Entity, IList->getInit(Index), *Field,
2264 TopLevelObject)) {
2265 hadError = true;
2266 ++Index;
2267 return;
2268 }
2269
2270 InitializedEntity MemberEntity =
2271 InitializedEntity::InitializeMember(*Field, &Entity);
2272
2273 if (isa<InitListExpr>(IList->getInit(Index)))
2274 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2275 StructuredList, StructuredIndex);
2276 else
2277 CheckImplicitInitList(MemberEntity, IList, Field->getType(), Index,
2278 StructuredList, StructuredIndex);
2279}
2280
2281/// Expand a field designator that refers to a member of an
2282/// anonymous struct or union into a series of field designators that
2283/// refers to the field within the appropriate subobject.
2284///
2285static void ExpandAnonymousFieldDesignator(Sema &SemaRef,
2286 DesignatedInitExpr *DIE,
2287 unsigned DesigIdx,
2288 IndirectFieldDecl *IndirectField) {
2289 typedef DesignatedInitExpr::Designator Designator;
2290
2291 // Build the replacement designators.
2292 SmallVector<Designator, 4> Replacements;
2293 for (IndirectFieldDecl::chain_iterator PI = IndirectField->chain_begin(),
2294 PE = IndirectField->chain_end(); PI != PE; ++PI) {
2295 if (PI + 1 == PE)
2296 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
2297 DIE->getDesignator(DesigIdx)->getDotLoc(),
2298 DIE->getDesignator(DesigIdx)->getFieldLoc()));
2299 else
2300 Replacements.push_back(Designator((IdentifierInfo *)nullptr,
2301 SourceLocation(), SourceLocation()));
2302 assert(isa<FieldDecl>(*PI))((isa<FieldDecl>(*PI)) ? static_cast<void> (0) : __assert_fail
("isa<FieldDecl>(*PI)", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 2302, __PRETTY_FUNCTION__))
;
2303 Replacements.back().setField(cast<FieldDecl>(*PI));
2304 }
2305
2306 // Expand the current designator into the set of replacement
2307 // designators, so we have a full subobject path down to where the
2308 // member of the anonymous struct/union is actually stored.
2309 DIE->ExpandDesignator(SemaRef.Context, DesigIdx, &Replacements[0],
2310 &Replacements[0] + Replacements.size());
2311}
2312
2313static DesignatedInitExpr *CloneDesignatedInitExpr(Sema &SemaRef,
2314 DesignatedInitExpr *DIE) {
2315 unsigned NumIndexExprs = DIE->getNumSubExprs() - 1;
2316 SmallVector<Expr*, 4> IndexExprs(NumIndexExprs);
2317 for (unsigned I = 0; I < NumIndexExprs; ++I)
2318 IndexExprs[I] = DIE->getSubExpr(I + 1);
2319 return DesignatedInitExpr::Create(SemaRef.Context, DIE->designators(),
2320 IndexExprs,
2321 DIE->getEqualOrColonLoc(),
2322 DIE->usesGNUSyntax(), DIE->getInit());
2323}
2324
2325namespace {
2326
2327// Callback to only accept typo corrections that are for field members of
2328// the given struct or union.
2329class FieldInitializerValidatorCCC final : public CorrectionCandidateCallback {
2330 public:
2331 explicit FieldInitializerValidatorCCC(RecordDecl *RD)
2332 : Record(RD) {}
2333
2334 bool ValidateCandidate(const TypoCorrection &candidate) override {
2335 FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>();
2336 return FD && FD->getDeclContext()->getRedeclContext()->Equals(Record);
2337 }
2338
2339 std::unique_ptr<CorrectionCandidateCallback> clone() override {
2340 return std::make_unique<FieldInitializerValidatorCCC>(*this);
2341 }
2342
2343 private:
2344 RecordDecl *Record;
2345};
2346
2347} // end anonymous namespace
2348
2349/// Check the well-formedness of a C99 designated initializer.
2350///
2351/// Determines whether the designated initializer @p DIE, which
2352/// resides at the given @p Index within the initializer list @p
2353/// IList, is well-formed for a current object of type @p DeclType
2354/// (C99 6.7.8). The actual subobject that this designator refers to
2355/// within the current subobject is returned in either
2356/// @p NextField or @p NextElementIndex (whichever is appropriate).
2357///
2358/// @param IList The initializer list in which this designated
2359/// initializer occurs.
2360///
2361/// @param DIE The designated initializer expression.
2362///
2363/// @param DesigIdx The index of the current designator.
2364///
2365/// @param CurrentObjectType The type of the "current object" (C99 6.7.8p17),
2366/// into which the designation in @p DIE should refer.
2367///
2368/// @param NextField If non-NULL and the first designator in @p DIE is
2369/// a field, this will be set to the field declaration corresponding
2370/// to the field named by the designator. On input, this is expected to be
2371/// the next field that would be initialized in the absence of designation,
2372/// if the complete object being initialized is a struct.
2373///
2374/// @param NextElementIndex If non-NULL and the first designator in @p
2375/// DIE is an array designator or GNU array-range designator, this
2376/// will be set to the last index initialized by this designator.
2377///
2378/// @param Index Index into @p IList where the designated initializer
2379/// @p DIE occurs.
2380///
2381/// @param StructuredList The initializer list expression that
2382/// describes all of the subobject initializers in the order they'll
2383/// actually be initialized.
2384///
2385/// @returns true if there was an error, false otherwise.
2386bool
2387InitListChecker::CheckDesignatedInitializer(const InitializedEntity &Entity,
2388 InitListExpr *IList,
2389 DesignatedInitExpr *DIE,
2390 unsigned DesigIdx,
2391 QualType &CurrentObjectType,
2392 RecordDecl::field_iterator *NextField,
2393 llvm::APSInt *NextElementIndex,
2394 unsigned &Index,
2395 InitListExpr *StructuredList,
2396 unsigned &StructuredIndex,
2397 bool FinishSubobjectInit,
2398 bool TopLevelObject) {
2399 if (DesigIdx == DIE->size()) {
2400 // C++20 designated initialization can result in direct-list-initialization
2401 // of the designated subobject. This is the only way that we can end up
2402 // performing direct initialization as part of aggregate initialization, so
2403 // it needs special handling.
2404 if (DIE->isDirectInit()) {
2405 Expr *Init = DIE->getInit();
2406 assert(isa<InitListExpr>(Init) &&((isa<InitListExpr>(Init) && "designator result in direct non-list initialization?"
) ? static_cast<void> (0) : __assert_fail ("isa<InitListExpr>(Init) && \"designator result in direct non-list initialization?\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 2407, __PRETTY_FUNCTION__))
2407 "designator result in direct non-list initialization?")((isa<InitListExpr>(Init) && "designator result in direct non-list initialization?"
) ? static_cast<void> (0) : __assert_fail ("isa<InitListExpr>(Init) && \"designator result in direct non-list initialization?\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 2407, __PRETTY_FUNCTION__))
;
2408 InitializationKind Kind = InitializationKind::CreateDirectList(
2409 DIE->getBeginLoc(), Init->getBeginLoc(), Init->getEndLoc());
2410 InitializationSequence Seq(SemaRef, Entity, Kind, Init,
2411 /*TopLevelOfInitList*/ true);
2412 if (StructuredList) {
2413 ExprResult Result = VerifyOnly
2414 ? getDummyInit()
2415 : Seq.Perform(SemaRef, Entity, Kind, Init);
2416 UpdateStructuredListElement(StructuredList, StructuredIndex,
2417 Result.get());
2418 }
2419 ++Index;
2420 return !Seq;
2421 }
2422
2423 // Check the actual initialization for the designated object type.
2424 bool prevHadError = hadError;
2425
2426 // Temporarily remove the designator expression from the
2427 // initializer list that the child calls see, so that we don't try
2428 // to re-process the designator.
2429 unsigned OldIndex = Index;
2430 IList->setInit(OldIndex, DIE->getInit());
2431
2432 CheckSubElementType(Entity, IList, CurrentObjectType, Index, StructuredList,
2433 StructuredIndex, /*DirectlyDesignated=*/true);
2434
2435 // Restore the designated initializer expression in the syntactic
2436 // form of the initializer list.
2437 if (IList->getInit(OldIndex) != DIE->getInit())
2438 DIE->setInit(IList->getInit(OldIndex));
2439 IList->setInit(OldIndex, DIE);
2440
2441 return hadError && !prevHadError;
2442 }
2443
2444 DesignatedInitExpr::Designator *D = DIE->getDesignator(DesigIdx);
2445 bool IsFirstDesignator = (DesigIdx == 0);
2446 if (IsFirstDesignator ? FullyStructuredList : StructuredList) {
2447 // Determine the structural initializer list that corresponds to the
2448 // current subobject.
2449 if (IsFirstDesignator)
2450 StructuredList = FullyStructuredList;
2451 else {
2452 Expr *ExistingInit = StructuredIndex < StructuredList->getNumInits() ?
2453 StructuredList->getInit(StructuredIndex) : nullptr;
2454 if (!ExistingInit && StructuredList->hasArrayFiller())
2455 ExistingInit = StructuredList->getArrayFiller();
2456
2457 if (!ExistingInit)
2458 StructuredList = getStructuredSubobjectInit(
2459 IList, Index, CurrentObjectType, StructuredList, StructuredIndex,
2460 SourceRange(D->getBeginLoc(), DIE->getEndLoc()));
2461 else if (InitListExpr *Result = dyn_cast<InitListExpr>(ExistingInit))
2462 StructuredList = Result;
2463 else {
2464 // We are creating an initializer list that initializes the
2465 // subobjects of the current object, but there was already an
2466 // initialization that completely initialized the current
2467 // subobject, e.g., by a compound literal:
2468 //
2469 // struct X { int a, b; };
2470 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
2471 //
2472 // Here, xs[0].a == 1 and xs[0].b == 3, since the second,
2473 // designated initializer re-initializes only its current object
2474 // subobject [0].b.
2475 diagnoseInitOverride(ExistingInit,
2476 SourceRange(D->getBeginLoc(), DIE->getEndLoc()),
2477 /*FullyOverwritten=*/false);
2478
2479 if (!VerifyOnly) {
2480 if (DesignatedInitUpdateExpr *E =
2481 dyn_cast<DesignatedInitUpdateExpr>(ExistingInit))
2482 StructuredList = E->getUpdater();
2483 else {
2484 DesignatedInitUpdateExpr *DIUE = new (SemaRef.Context)
2485 DesignatedInitUpdateExpr(SemaRef.Context, D->getBeginLoc(),
2486 ExistingInit, DIE->getEndLoc());
2487 StructuredList->updateInit(SemaRef.Context, StructuredIndex, DIUE);
2488 StructuredList = DIUE->getUpdater();
2489 }
2490 } else {
2491 // We don't need to track the structured representation of a
2492 // designated init update of an already-fully-initialized object in
2493 // verify-only mode. The only reason we would need the structure is
2494 // to determine where the uninitialized "holes" are, and in this
2495 // case, we know there aren't any and we can't introduce any.
2496 StructuredList = nullptr;
2497 }
2498 }
2499 }
2500 }
2501
2502 if (D->isFieldDesignator()) {
2503 // C99 6.7.8p7:
2504 //
2505 // If a designator has the form
2506 //
2507 // . identifier
2508 //
2509 // then the current object (defined below) shall have
2510 // structure or union type and the identifier shall be the
2511 // name of a member of that type.
2512 const RecordType *RT = CurrentObjectType->getAs<RecordType>();
2513 if (!RT) {
2514 SourceLocation Loc = D->getDotLoc();
2515 if (Loc.isInvalid())
2516 Loc = D->getFieldLoc();
2517 if (!VerifyOnly)
2518 SemaRef.Diag(Loc, diag::err_field_designator_non_aggr)
2519 << SemaRef.getLangOpts().CPlusPlus << CurrentObjectType;
2520 ++Index;
2521 return true;
2522 }
2523
2524 FieldDecl *KnownField = D->getField();
2525 if (!KnownField) {
2526 IdentifierInfo *FieldName = D->getFieldName();
2527 DeclContext::lookup_result Lookup = RT->getDecl()->lookup(FieldName);
2528 for (NamedDecl *ND : Lookup) {
2529 if (auto *FD = dyn_cast<FieldDecl>(ND)) {
2530 KnownField = FD;
2531 break;
2532 }
2533 if (auto *IFD = dyn_cast<IndirectFieldDecl>(ND)) {
2534 // In verify mode, don't modify the original.
2535 if (VerifyOnly)
2536 DIE = CloneDesignatedInitExpr(SemaRef, DIE);
2537 ExpandAnonymousFieldDesignator(SemaRef, DIE, DesigIdx, IFD);
2538 D = DIE->getDesignator(DesigIdx);
2539 KnownField = cast<FieldDecl>(*IFD->chain_begin());
2540 break;
2541 }
2542 }
2543 if (!KnownField) {
2544 if (VerifyOnly) {
2545 ++Index;
2546 return true; // No typo correction when just trying this out.
2547 }
2548
2549 // Name lookup found something, but it wasn't a field.
2550 if (!Lookup.empty()) {
2551 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_nonfield)
2552 << FieldName;
2553 SemaRef.Diag(Lookup.front()->getLocation(),
2554 diag::note_field_designator_found);
2555 ++Index;
2556 return true;
2557 }
2558
2559 // Name lookup didn't find anything.
2560 // Determine whether this was a typo for another field name.
2561 FieldInitializerValidatorCCC CCC(RT->getDecl());
2562 if (TypoCorrection Corrected = SemaRef.CorrectTypo(
2563 DeclarationNameInfo(FieldName, D->getFieldLoc()),
2564 Sema::LookupMemberName, /*Scope=*/nullptr, /*SS=*/nullptr, CCC,
2565 Sema::CTK_ErrorRecovery, RT->getDecl())) {
2566 SemaRef.diagnoseTypo(
2567 Corrected,
2568 SemaRef.PDiag(diag::err_field_designator_unknown_suggest)
2569 << FieldName << CurrentObjectType);
2570 KnownField = Corrected.getCorrectionDeclAs<FieldDecl>();
2571 hadError = true;
2572 } else {
2573 // Typo correction didn't find anything.
2574 SemaRef.Diag(D->getFieldLoc(), diag::err_field_designator_unknown)
2575 << FieldName << CurrentObjectType;
2576 ++Index;
2577 return true;
2578 }
2579 }
2580 }
2581
2582 unsigned NumBases = 0;
2583 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
2584 NumBases = CXXRD->getNumBases();
2585
2586 unsigned FieldIndex = NumBases;
2587
2588 for (auto *FI : RT->getDecl()->fields()) {
2589 if (FI->isUnnamedBitfield())
2590 continue;
2591 if (declaresSameEntity(KnownField, FI)) {
2592 KnownField = FI;
2593 break;
2594 }
2595 ++FieldIndex;
2596 }
2597
2598 RecordDecl::field_iterator Field =
2599 RecordDecl::field_iterator(DeclContext::decl_iterator(KnownField));
2600
2601 // All of the fields of a union are located at the same place in
2602 // the initializer list.
2603 if (RT->getDecl()->isUnion()) {
2604 FieldIndex = 0;
2605 if (StructuredList) {
2606 FieldDecl *CurrentField = StructuredList->getInitializedFieldInUnion();
2607 if (CurrentField && !declaresSameEntity(CurrentField, *Field)) {
2608 assert(StructuredList->getNumInits() == 1((StructuredList->getNumInits() == 1 && "A union should never have more than one initializer!"
) ? static_cast<void> (0) : __assert_fail ("StructuredList->getNumInits() == 1 && \"A union should never have more than one initializer!\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 2609, __PRETTY_FUNCTION__))
2609 && "A union should never have more than one initializer!")((StructuredList->getNumInits() == 1 && "A union should never have more than one initializer!"
) ? static_cast<void> (0) : __assert_fail ("StructuredList->getNumInits() == 1 && \"A union should never have more than one initializer!\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 2609, __PRETTY_FUNCTION__))
;
2610
2611 Expr *ExistingInit = StructuredList->getInit(0);
2612 if (ExistingInit) {
2613 // We're about to throw away an initializer, emit warning.
2614 diagnoseInitOverride(
2615 ExistingInit, SourceRange(D->getBeginLoc(), DIE->getEndLoc()));
2616 }
2617
2618 // remove existing initializer
2619 StructuredList->resizeInits(SemaRef.Context, 0);
2620 StructuredList->setInitializedFieldInUnion(nullptr);
2621 }
2622
2623 StructuredList->setInitializedFieldInUnion(*Field);
2624 }
2625 }
2626
2627 // Make sure we can use this declaration.
2628 bool InvalidUse;
2629 if (VerifyOnly)
2630 InvalidUse = !SemaRef.CanUseDecl(*Field, TreatUnavailableAsInvalid);
2631 else
2632 InvalidUse = SemaRef.DiagnoseUseOfDecl(*Field, D->getFieldLoc());
2633 if (InvalidUse) {
2634 ++Index;
2635 return true;
2636 }
2637
2638 // C++20 [dcl.init.list]p3:
2639 // The ordered identifiers in the designators of the designated-
2640 // initializer-list shall form a subsequence of the ordered identifiers
2641 // in the direct non-static data members of T.
2642 //
2643 // Note that this is not a condition on forming the aggregate
2644 // initialization, only on actually performing initialization,
2645 // so it is not checked in VerifyOnly mode.
2646 //
2647 // FIXME: This is the only reordering diagnostic we produce, and it only
2648 // catches cases where we have a top-level field designator that jumps
2649 // backwards. This is the only such case that is reachable in an
2650 // otherwise-valid C++20 program, so is the only case that's required for
2651 // conformance, but for consistency, we should diagnose all the other
2652 // cases where a designator takes us backwards too.
2653 if (IsFirstDesignator && !VerifyOnly && SemaRef.getLangOpts().CPlusPlus &&
2654 NextField &&
2655 (*NextField == RT->getDecl()->field_end() ||
2656 (*NextField)->getFieldIndex() > Field->getFieldIndex() + 1)) {
2657 // Find the field that we just initialized.
2658 FieldDecl *PrevField = nullptr;
2659 for (auto FI = RT->getDecl()->field_begin();
2660 FI != RT->getDecl()->field_end(); ++FI) {
2661 if (FI->isUnnamedBitfield())
2662 continue;
2663 if (*NextField != RT->getDecl()->field_end() &&
2664 declaresSameEntity(*FI, **NextField))
2665 break;
2666 PrevField = *FI;
2667 }
2668
2669 if (PrevField &&
2670 PrevField->getFieldIndex() > KnownField->getFieldIndex()) {
2671 SemaRef.Diag(DIE->getBeginLoc(), diag::ext_designated_init_reordered)
2672 << KnownField << PrevField << DIE->getSourceRange();
2673
2674 unsigned OldIndex = NumBases + PrevField->getFieldIndex();
2675 if (StructuredList && OldIndex <= StructuredList->getNumInits()) {
2676 if (Expr *PrevInit = StructuredList->getInit(OldIndex)) {
2677 SemaRef.Diag(PrevInit->getBeginLoc(),
2678 diag::note_previous_field_init)
2679 << PrevField << PrevInit->getSourceRange();
2680 }
2681 }
2682 }
2683 }
2684
2685
2686 // Update the designator with the field declaration.
2687 if (!VerifyOnly)
2688 D->setField(*Field);
2689
2690 // Make sure that our non-designated initializer list has space
2691 // for a subobject corresponding to this field.
2692 if (StructuredList && FieldIndex >= StructuredList->getNumInits())
2693 StructuredList->resizeInits(SemaRef.Context, FieldIndex + 1);
2694
2695 // This designator names a flexible array member.
2696 if (Field->getType()->isIncompleteArrayType()) {
2697 bool Invalid = false;
2698 if ((DesigIdx + 1) != DIE->size()) {
2699 // We can't designate an object within the flexible array
2700 // member (because GCC doesn't allow it).
2701 if (!VerifyOnly) {
2702 DesignatedInitExpr::Designator *NextD
2703 = DIE->getDesignator(DesigIdx + 1);
2704 SemaRef.Diag(NextD->getBeginLoc(),
2705 diag::err_designator_into_flexible_array_member)
2706 << SourceRange(NextD->getBeginLoc(), DIE->getEndLoc());
2707 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2708 << *Field;
2709 }
2710 Invalid = true;
2711 }
2712
2713 if (!hadError && !isa<InitListExpr>(DIE->getInit()) &&
2714 !isa<StringLiteral>(DIE->getInit())) {
2715 // The initializer is not an initializer list.
2716 if (!VerifyOnly) {
2717 SemaRef.Diag(DIE->getInit()->getBeginLoc(),
2718 diag::err_flexible_array_init_needs_braces)
2719 << DIE->getInit()->getSourceRange();
2720 SemaRef.Diag(Field->getLocation(), diag::note_flexible_array_member)
2721 << *Field;
2722 }
2723 Invalid = true;
2724 }
2725
2726 // Check GNU flexible array initializer.
2727 if (!Invalid && CheckFlexibleArrayInit(Entity, DIE->getInit(), *Field,
2728 TopLevelObject))
2729 Invalid = true;
2730
2731 if (Invalid) {
2732 ++Index;
2733 return true;
2734 }
2735
2736 // Initialize the array.
2737 bool prevHadError = hadError;
2738 unsigned newStructuredIndex = FieldIndex;
2739 unsigned OldIndex = Index;
2740 IList->setInit(Index, DIE->getInit());
2741
2742 InitializedEntity MemberEntity =
2743 InitializedEntity::InitializeMember(*Field, &Entity);
2744 CheckSubElementType(MemberEntity, IList, Field->getType(), Index,
2745 StructuredList, newStructuredIndex);
2746
2747 IList->setInit(OldIndex, DIE);
2748 if (hadError && !prevHadError) {
2749 ++Field;
2750 ++FieldIndex;
2751 if (NextField)
2752 *NextField = Field;
2753 StructuredIndex = FieldIndex;
2754 return true;
2755 }
2756 } else {
2757 // Recurse to check later designated subobjects.
2758 QualType FieldType = Field->getType();
2759 unsigned newStructuredIndex = FieldIndex;
2760
2761 InitializedEntity MemberEntity =
2762 InitializedEntity::InitializeMember(*Field, &Entity);
2763 if (CheckDesignatedInitializer(MemberEntity, IList, DIE, DesigIdx + 1,
2764 FieldType, nullptr, nullptr, Index,
2765 StructuredList, newStructuredIndex,
2766 FinishSubobjectInit, false))
2767 return true;
2768 }
2769
2770 // Find the position of the next field to be initialized in this
2771 // subobject.
2772 ++Field;
2773 ++FieldIndex;
2774
2775 // If this the first designator, our caller will continue checking
2776 // the rest of this struct/class/union subobject.
2777 if (IsFirstDesignator) {
2778 if (NextField)
2779 *NextField = Field;
2780 StructuredIndex = FieldIndex;
2781 return false;
2782 }
2783
2784 if (!FinishSubobjectInit)
2785 return false;
2786
2787 // We've already initialized something in the union; we're done.
2788 if (RT->getDecl()->isUnion())
2789 return hadError;
2790
2791 // Check the remaining fields within this class/struct/union subobject.
2792 bool prevHadError = hadError;
2793
2794 auto NoBases =
2795 CXXRecordDecl::base_class_range(CXXRecordDecl::base_class_iterator(),
2796 CXXRecordDecl::base_class_iterator());
2797 CheckStructUnionTypes(Entity, IList, CurrentObjectType, NoBases, Field,
2798 false, Index, StructuredList, FieldIndex);
2799 return hadError && !prevHadError;
2800 }
2801
2802 // C99 6.7.8p6:
2803 //
2804 // If a designator has the form
2805 //
2806 // [ constant-expression ]
2807 //
2808 // then the current object (defined below) shall have array
2809 // type and the expression shall be an integer constant
2810 // expression. If the array is of unknown size, any
2811 // nonnegative value is valid.
2812 //
2813 // Additionally, cope with the GNU extension that permits
2814 // designators of the form
2815 //
2816 // [ constant-expression ... constant-expression ]
2817 const ArrayType *AT = SemaRef.Context.getAsArrayType(CurrentObjectType);
2818 if (!AT) {
2819 if (!VerifyOnly)
2820 SemaRef.Diag(D->getLBracketLoc(), diag::err_array_designator_non_array)
2821 << CurrentObjectType;
2822 ++Index;
2823 return true;
2824 }
2825
2826 Expr *IndexExpr = nullptr;
2827 llvm::APSInt DesignatedStartIndex, DesignatedEndIndex;
2828 if (D->isArrayDesignator()) {
2829 IndexExpr = DIE->getArrayIndex(*D);
2830 DesignatedStartIndex = IndexExpr->EvaluateKnownConstInt(SemaRef.Context);
2831 DesignatedEndIndex = DesignatedStartIndex;
2832 } else {
2833 assert(D->isArrayRangeDesignator() && "Need array-range designator")((D->isArrayRangeDesignator() && "Need array-range designator"
) ? static_cast<void> (0) : __assert_fail ("D->isArrayRangeDesignator() && \"Need array-range designator\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 2833, __PRETTY_FUNCTION__))
;
2834
2835 DesignatedStartIndex =
2836 DIE->getArrayRangeStart(*D)->EvaluateKnownConstInt(SemaRef.Context);
2837 DesignatedEndIndex =
2838 DIE->getArrayRangeEnd(*D)->EvaluateKnownConstInt(SemaRef.Context);
2839 IndexExpr = DIE->getArrayRangeEnd(*D);
2840
2841 // Codegen can't handle evaluating array range designators that have side
2842 // effects, because we replicate the AST value for each initialized element.
2843 // As such, set the sawArrayRangeDesignator() bit if we initialize multiple
2844 // elements with something that has a side effect, so codegen can emit an
2845 // "error unsupported" error instead of miscompiling the app.
2846 if (DesignatedStartIndex.getZExtValue()!=DesignatedEndIndex.getZExtValue()&&
2847 DIE->getInit()->HasSideEffects(SemaRef.Context) && !VerifyOnly)
2848 FullyStructuredList->sawArrayRangeDesignator();
2849 }
2850
2851 if (isa<ConstantArrayType>(AT)) {
2852 llvm::APSInt MaxElements(cast<ConstantArrayType>(AT)->getSize(), false);
2853 DesignatedStartIndex
2854 = DesignatedStartIndex.extOrTrunc(MaxElements.getBitWidth());
2855 DesignatedStartIndex.setIsUnsigned(MaxElements.isUnsigned());
2856 DesignatedEndIndex
2857 = DesignatedEndIndex.extOrTrunc(MaxElements.getBitWidth());
2858 DesignatedEndIndex.setIsUnsigned(MaxElements.isUnsigned());
2859 if (DesignatedEndIndex >= MaxElements) {
2860 if (!VerifyOnly)
2861 SemaRef.Diag(IndexExpr->getBeginLoc(),
2862 diag::err_array_designator_too_large)
2863 << DesignatedEndIndex.toString(10) << MaxElements.toString(10)
2864 << IndexExpr->getSourceRange();
2865 ++Index;
2866 return true;
2867 }
2868 } else {
2869 unsigned DesignatedIndexBitWidth =
2870 ConstantArrayType::getMaxSizeBits(SemaRef.Context);
2871 DesignatedStartIndex =
2872 DesignatedStartIndex.extOrTrunc(DesignatedIndexBitWidth);
2873 DesignatedEndIndex =
2874 DesignatedEndIndex.extOrTrunc(DesignatedIndexBitWidth);
2875 DesignatedStartIndex.setIsUnsigned(true);
2876 DesignatedEndIndex.setIsUnsigned(true);
2877 }
2878
2879 bool IsStringLiteralInitUpdate =
2880 StructuredList && StructuredList->isStringLiteralInit();
2881 if (IsStringLiteralInitUpdate && VerifyOnly) {
2882 // We're just verifying an update to a string literal init. We don't need
2883 // to split the string up into individual characters to do that.
2884 StructuredList = nullptr;
2885 } else if (IsStringLiteralInitUpdate) {
2886 // We're modifying a string literal init; we have to decompose the string
2887 // so we can modify the individual characters.
2888 ASTContext &Context = SemaRef.Context;
2889 Expr *SubExpr = StructuredList->getInit(0)->IgnoreParens();
2890
2891 // Compute the character type
2892 QualType CharTy = AT->getElementType();
2893
2894 // Compute the type of the integer literals.
2895 QualType PromotedCharTy = CharTy;
2896 if (CharTy->isPromotableIntegerType())
2897 PromotedCharTy = Context.getPromotedIntegerType(CharTy);
2898 unsigned PromotedCharTyWidth = Context.getTypeSize(PromotedCharTy);
2899
2900 if (StringLiteral *SL = dyn_cast<StringLiteral>(SubExpr)) {
2901 // Get the length of the string.
2902 uint64_t StrLen = SL->getLength();
2903 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2904 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2905 StructuredList->resizeInits(Context, StrLen);
2906
2907 // Build a literal for each character in the string, and put them into
2908 // the init list.
2909 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2910 llvm::APInt CodeUnit(PromotedCharTyWidth, SL->getCodeUnit(i));
2911 Expr *Init = new (Context) IntegerLiteral(
2912 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2913 if (CharTy != PromotedCharTy)
2914 Init =
2915 ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast, Init,
2916 nullptr, VK_RValue, FPOptionsOverride());
2917 StructuredList->updateInit(Context, i, Init);
2918 }
2919 } else {
2920 ObjCEncodeExpr *E = cast<ObjCEncodeExpr>(SubExpr);
2921 std::string Str;
2922 Context.getObjCEncodingForType(E->getEncodedType(), Str);
2923
2924 // Get the length of the string.
2925 uint64_t StrLen = Str.size();
2926 if (cast<ConstantArrayType>(AT)->getSize().ult(StrLen))
2927 StrLen = cast<ConstantArrayType>(AT)->getSize().getZExtValue();
2928 StructuredList->resizeInits(Context, StrLen);
2929
2930 // Build a literal for each character in the string, and put them into
2931 // the init list.
2932 for (unsigned i = 0, e = StrLen; i != e; ++i) {
2933 llvm::APInt CodeUnit(PromotedCharTyWidth, Str[i]);
2934 Expr *Init = new (Context) IntegerLiteral(
2935 Context, CodeUnit, PromotedCharTy, SubExpr->getExprLoc());
2936 if (CharTy != PromotedCharTy)
2937 Init =
2938 ImplicitCastExpr::Create(Context, CharTy, CK_IntegralCast, Init,
2939 nullptr, VK_RValue, FPOptionsOverride());
2940 StructuredList->updateInit(Context, i, Init);
2941 }
2942 }
2943 }
2944
2945 // Make sure that our non-designated initializer list has space
2946 // for a subobject corresponding to this array element.
2947 if (StructuredList &&
2948 DesignatedEndIndex.getZExtValue() >= StructuredList->getNumInits())
2949 StructuredList->resizeInits(SemaRef.Context,
2950 DesignatedEndIndex.getZExtValue() + 1);
2951
2952 // Repeatedly perform subobject initializations in the range
2953 // [DesignatedStartIndex, DesignatedEndIndex].
2954
2955 // Move to the next designator
2956 unsigned ElementIndex = DesignatedStartIndex.getZExtValue();
2957 unsigned OldIndex = Index;
2958
2959 InitializedEntity ElementEntity =
2960 InitializedEntity::InitializeElement(SemaRef.Context, 0, Entity);
2961
2962 while (DesignatedStartIndex <= DesignatedEndIndex) {
2963 // Recurse to check later designated subobjects.
2964 QualType ElementType = AT->getElementType();
2965 Index = OldIndex;
2966
2967 ElementEntity.setElementIndex(ElementIndex);
2968 if (CheckDesignatedInitializer(
2969 ElementEntity, IList, DIE, DesigIdx + 1, ElementType, nullptr,
2970 nullptr, Index, StructuredList, ElementIndex,
2971 FinishSubobjectInit && (DesignatedStartIndex == DesignatedEndIndex),
2972 false))
2973 return true;
2974
2975 // Move to the next index in the array that we'll be initializing.
2976 ++DesignatedStartIndex;
2977 ElementIndex = DesignatedStartIndex.getZExtValue();
2978 }
2979
2980 // If this the first designator, our caller will continue checking
2981 // the rest of this array subobject.
2982 if (IsFirstDesignator) {
2983 if (NextElementIndex)
2984 *NextElementIndex = DesignatedStartIndex;
2985 StructuredIndex = ElementIndex;
2986 return false;
2987 }
2988
2989 if (!FinishSubobjectInit)
2990 return false;
2991
2992 // Check the remaining elements within this array subobject.
2993 bool prevHadError = hadError;
2994 CheckArrayType(Entity, IList, CurrentObjectType, DesignatedStartIndex,
2995 /*SubobjectIsDesignatorContext=*/false, Index,
2996 StructuredList, ElementIndex);
2997 return hadError && !prevHadError;
2998}
2999
3000// Get the structured initializer list for a subobject of type
3001// @p CurrentObjectType.
3002InitListExpr *
3003InitListChecker::getStructuredSubobjectInit(InitListExpr *IList, unsigned Index,
3004 QualType CurrentObjectType,
3005 InitListExpr *StructuredList,
3006 unsigned StructuredIndex,
3007 SourceRange InitRange,
3008 bool IsFullyOverwritten) {
3009 if (!StructuredList)
3010 return nullptr;
3011
3012 Expr *ExistingInit = nullptr;
3013 if (StructuredIndex < StructuredList->getNumInits())
3014 ExistingInit = StructuredList->getInit(StructuredIndex);
3015
3016 if (InitListExpr *Result = dyn_cast_or_null<InitListExpr>(ExistingInit))
3017 // There might have already been initializers for subobjects of the current
3018 // object, but a subsequent initializer list will overwrite the entirety
3019 // of the current object. (See DR 253 and C99 6.7.8p21). e.g.,
3020 //
3021 // struct P { char x[6]; };
3022 // struct P l = { .x[2] = 'x', .x = { [0] = 'f' } };
3023 //
3024 // The first designated initializer is ignored, and l.x is just "f".
3025 if (!IsFullyOverwritten)
3026 return Result;
3027
3028 if (ExistingInit) {
3029 // We are creating an initializer list that initializes the
3030 // subobjects of the current object, but there was already an
3031 // initialization that completely initialized the current
3032 // subobject:
3033 //
3034 // struct X { int a, b; };
3035 // struct X xs[] = { [0] = { 1, 2 }, [0].b = 3 };
3036 //
3037 // Here, xs[0].a == 1 and xs[0].b == 3, since the second,
3038 // designated initializer overwrites the [0].b initializer
3039 // from the prior initialization.
3040 //
3041 // When the existing initializer is an expression rather than an
3042 // initializer list, we cannot decompose and update it in this way.
3043 // For example:
3044 //
3045 // struct X xs[] = { [0] = (struct X) { 1, 2 }, [0].b = 3 };
3046 //
3047 // This case is handled by CheckDesignatedInitializer.
3048 diagnoseInitOverride(ExistingInit, InitRange);
3049 }
3050
3051 unsigned ExpectedNumInits = 0;
3052 if (Index < IList->getNumInits()) {
3053 if (auto *Init = dyn_cast_or_null<InitListExpr>(IList->getInit(Index)))
3054 ExpectedNumInits = Init->getNumInits();
3055 else
3056 ExpectedNumInits = IList->getNumInits() - Index;
3057 }
3058
3059 InitListExpr *Result =
3060 createInitListExpr(CurrentObjectType, InitRange, ExpectedNumInits);
3061
3062 // Link this new initializer list into the structured initializer
3063 // lists.
3064 StructuredList->updateInit(SemaRef.Context, StructuredIndex, Result);
3065 return Result;
3066}
3067
3068InitListExpr *
3069InitListChecker::createInitListExpr(QualType CurrentObjectType,
3070 SourceRange InitRange,
3071 unsigned ExpectedNumInits) {
3072 InitListExpr *Result
3073 = new (SemaRef.Context) InitListExpr(SemaRef.Context,
3074 InitRange.getBegin(), None,
3075 InitRange.getEnd());
3076
3077 QualType ResultType = CurrentObjectType;
3078 if (!ResultType->isArrayType())
3079 ResultType = ResultType.getNonLValueExprType(SemaRef.Context);
3080 Result->setType(ResultType);
3081
3082 // Pre-allocate storage for the structured initializer list.
3083 unsigned NumElements = 0;
3084
3085 if (const ArrayType *AType
3086 = SemaRef.Context.getAsArrayType(CurrentObjectType)) {
3087 if (const ConstantArrayType *CAType = dyn_cast<ConstantArrayType>(AType)) {
3088 NumElements = CAType->getSize().getZExtValue();
3089 // Simple heuristic so that we don't allocate a very large
3090 // initializer with many empty entries at the end.
3091 if (NumElements > ExpectedNumInits)
3092 NumElements = 0;
3093 }
3094 } else if (const VectorType *VType = CurrentObjectType->getAs<VectorType>()) {
3095 NumElements = VType->getNumElements();
3096 } else if (CurrentObjectType->isRecordType()) {
3097 NumElements = numStructUnionElements(CurrentObjectType);
3098 }
3099
3100 Result->reserveInits(SemaRef.Context, NumElements);
3101
3102 return Result;
3103}
3104
3105/// Update the initializer at index @p StructuredIndex within the
3106/// structured initializer list to the value @p expr.
3107void InitListChecker::UpdateStructuredListElement(InitListExpr *StructuredList,
3108 unsigned &StructuredIndex,
3109 Expr *expr) {
3110 // No structured initializer list to update
3111 if (!StructuredList)
3112 return;
3113
3114 if (Expr *PrevInit = StructuredList->updateInit(SemaRef.Context,
3115 StructuredIndex, expr)) {
3116 // This initializer overwrites a previous initializer.
3117 // No need to diagnose when `expr` is nullptr because a more relevant
3118 // diagnostic has already been issued and this diagnostic is potentially
3119 // noise.
3120 if (expr)
3121 diagnoseInitOverride(PrevInit, expr->getSourceRange());
3122 }
3123
3124 ++StructuredIndex;
3125}
3126
3127/// Determine whether we can perform aggregate initialization for the purposes
3128/// of overload resolution.
3129bool Sema::CanPerformAggregateInitializationForOverloadResolution(
3130 const InitializedEntity &Entity, InitListExpr *From) {
3131 QualType Type = Entity.getType();
3132 InitListChecker Check(*this, Entity, From, Type, /*VerifyOnly=*/true,
3133 /*TreatUnavailableAsInvalid=*/false,
3134 /*InOverloadResolution=*/true);
3135 return !Check.HadError();
3136}
3137
3138/// Check that the given Index expression is a valid array designator
3139/// value. This is essentially just a wrapper around
3140/// VerifyIntegerConstantExpression that also checks for negative values
3141/// and produces a reasonable diagnostic if there is a
3142/// failure. Returns the index expression, possibly with an implicit cast
3143/// added, on success. If everything went okay, Value will receive the
3144/// value of the constant expression.
3145static ExprResult
3146CheckArrayDesignatorExpr(Sema &S, Expr *Index, llvm::APSInt &Value) {
3147 SourceLocation Loc = Index->getBeginLoc();
3148
3149 // Make sure this is an integer constant expression.
3150 ExprResult Result =
3151 S.VerifyIntegerConstantExpression(Index, &Value, Sema::AllowFold);
3152 if (Result.isInvalid())
3153 return Result;
3154
3155 if (Value.isSigned() && Value.isNegative())
3156 return S.Diag(Loc, diag::err_array_designator_negative)
3157 << Value.toString(10) << Index->getSourceRange();
3158
3159 Value.setIsUnsigned(true);
3160 return Result;
3161}
3162
3163ExprResult Sema::ActOnDesignatedInitializer(Designation &Desig,
3164 SourceLocation EqualOrColonLoc,
3165 bool GNUSyntax,
3166 ExprResult Init) {
3167 typedef DesignatedInitExpr::Designator ASTDesignator;
3168
3169 bool Invalid = false;
3170 SmallVector<ASTDesignator, 32> Designators;
3171 SmallVector<Expr *, 32> InitExpressions;
3172
3173 // Build designators and check array designator expressions.
3174 for (unsigned Idx = 0; Idx < Desig.getNumDesignators(); ++Idx) {
3175 const Designator &D = Desig.getDesignator(Idx);
3176 switch (D.getKind()) {
3177 case Designator::FieldDesignator:
3178 Designators.push_back(ASTDesignator(D.getField(), D.getDotLoc(),
3179 D.getFieldLoc()));
3180 break;
3181
3182 case Designator::ArrayDesignator: {
3183 Expr *Index = static_cast<Expr *>(D.getArrayIndex());
3184 llvm::APSInt IndexValue;
3185 if (!Index->isTypeDependent() && !Index->isValueDependent())
3186 Index = CheckArrayDesignatorExpr(*this, Index, IndexValue).get();
3187 if (!Index)
3188 Invalid = true;
3189 else {
3190 Designators.push_back(ASTDesignator(InitExpressions.size(),
3191 D.getLBracketLoc(),
3192 D.getRBracketLoc()));
3193 InitExpressions.push_back(Index);
3194 }
3195 break;
3196 }
3197
3198 case Designator::ArrayRangeDesignator: {
3199 Expr *StartIndex = static_cast<Expr *>(D.getArrayRangeStart());
3200 Expr *EndIndex = static_cast<Expr *>(D.getArrayRangeEnd());
3201 llvm::APSInt StartValue;
3202 llvm::APSInt EndValue;
3203 bool StartDependent = StartIndex->isTypeDependent() ||
3204 StartIndex->isValueDependent();
3205 bool EndDependent = EndIndex->isTypeDependent() ||
3206 EndIndex->isValueDependent();
3207 if (!StartDependent)
3208 StartIndex =
3209 CheckArrayDesignatorExpr(*this, StartIndex, StartValue).get();
3210 if (!EndDependent)
3211 EndIndex = CheckArrayDesignatorExpr(*this, EndIndex, EndValue).get();
3212
3213 if (!StartIndex || !EndIndex)
3214 Invalid = true;
3215 else {
3216 // Make sure we're comparing values with the same bit width.
3217 if (StartDependent || EndDependent) {
3218 // Nothing to compute.
3219 } else if (StartValue.getBitWidth() > EndValue.getBitWidth())
3220 EndValue = EndValue.extend(StartValue.getBitWidth());
3221 else if (StartValue.getBitWidth() < EndValue.getBitWidth())
3222 StartValue = StartValue.extend(EndValue.getBitWidth());
3223
3224 if (!StartDependent && !EndDependent && EndValue < StartValue) {
3225 Diag(D.getEllipsisLoc(), diag::err_array_designator_empty_range)
3226 << StartValue.toString(10) << EndValue.toString(10)
3227 << StartIndex->getSourceRange() << EndIndex->getSourceRange();
3228 Invalid = true;
3229 } else {
3230 Designators.push_back(ASTDesignator(InitExpressions.size(),
3231 D.getLBracketLoc(),
3232 D.getEllipsisLoc(),
3233 D.getRBracketLoc()));
3234 InitExpressions.push_back(StartIndex);
3235 InitExpressions.push_back(EndIndex);
3236 }
3237 }
3238 break;
3239 }
3240 }
3241 }
3242
3243 if (Invalid || Init.isInvalid())
3244 return ExprError();
3245
3246 // Clear out the expressions within the designation.
3247 Desig.ClearExprs(*this);
3248
3249 return DesignatedInitExpr::Create(Context, Designators, InitExpressions,
3250 EqualOrColonLoc, GNUSyntax,
3251 Init.getAs<Expr>());
3252}
3253
3254//===----------------------------------------------------------------------===//
3255// Initialization entity
3256//===----------------------------------------------------------------------===//
3257
3258InitializedEntity::InitializedEntity(ASTContext &Context, unsigned Index,
3259 const InitializedEntity &Parent)
3260 : Parent(&Parent), Index(Index)
3261{
3262 if (const ArrayType *AT = Context.getAsArrayType(Parent.getType())) {
3263 Kind = EK_ArrayElement;
3264 Type = AT->getElementType();
3265 } else if (const VectorType *VT = Parent.getType()->getAs<VectorType>()) {
3266 Kind = EK_VectorElement;
3267 Type = VT->getElementType();
3268 } else {
3269 const ComplexType *CT = Parent.getType()->getAs<ComplexType>();
3270 assert(CT && "Unexpected type")((CT && "Unexpected type") ? static_cast<void> (
0) : __assert_fail ("CT && \"Unexpected type\"", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3270, __PRETTY_FUNCTION__))
;
3271 Kind = EK_ComplexElement;
3272 Type = CT->getElementType();
3273 }
3274}
3275
3276InitializedEntity
3277InitializedEntity::InitializeBase(ASTContext &Context,
3278 const CXXBaseSpecifier *Base,
3279 bool IsInheritedVirtualBase,
3280 const InitializedEntity *Parent) {
3281 InitializedEntity Result;
3282 Result.Kind = EK_Base;
3283 Result.Parent = Parent;
3284 Result.Base = reinterpret_cast<uintptr_t>(Base);
3285 if (IsInheritedVirtualBase)
3286 Result.Base |= 0x01;
3287
3288 Result.Type = Base->getType();
3289 return Result;
3290}
3291
3292DeclarationName InitializedEntity::getName() const {
3293 switch (getKind()) {
3294 case EK_Parameter:
3295 case EK_Parameter_CF_Audited: {
3296 ParmVarDecl *D = reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
3297 return (D ? D->getDeclName() : DeclarationName());
3298 }
3299
3300 case EK_Variable:
3301 case EK_Member:
3302 case EK_Binding:
3303 case EK_TemplateParameter:
3304 return Variable.VariableOrMember->getDeclName();
3305
3306 case EK_LambdaCapture:
3307 return DeclarationName(Capture.VarID);
3308
3309 case EK_Result:
3310 case EK_StmtExprResult:
3311 case EK_Exception:
3312 case EK_New:
3313 case EK_Temporary:
3314 case EK_Base:
3315 case EK_Delegating:
3316 case EK_ArrayElement:
3317 case EK_VectorElement:
3318 case EK_ComplexElement:
3319 case EK_BlockElement:
3320 case EK_LambdaToBlockConversionBlockElement:
3321 case EK_CompoundLiteralInit:
3322 case EK_RelatedResult:
3323 return DeclarationName();
3324 }
3325
3326 llvm_unreachable("Invalid EntityKind!")::llvm::llvm_unreachable_internal("Invalid EntityKind!", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3326)
;
3327}
3328
3329ValueDecl *InitializedEntity::getDecl() const {
3330 switch (getKind()) {
3331 case EK_Variable:
3332 case EK_Member:
3333 case EK_Binding:
3334 case EK_TemplateParameter:
3335 return Variable.VariableOrMember;
3336
3337 case EK_Parameter:
3338 case EK_Parameter_CF_Audited:
3339 return reinterpret_cast<ParmVarDecl*>(Parameter & ~0x1);
3340
3341 case EK_Result:
3342 case EK_StmtExprResult:
3343 case EK_Exception:
3344 case EK_New:
3345 case EK_Temporary:
3346 case EK_Base:
3347 case EK_Delegating:
3348 case EK_ArrayElement:
3349 case EK_VectorElement:
3350 case EK_ComplexElement:
3351 case EK_BlockElement:
3352 case EK_LambdaToBlockConversionBlockElement:
3353 case EK_LambdaCapture:
3354 case EK_CompoundLiteralInit:
3355 case EK_RelatedResult:
3356 return nullptr;
3357 }
3358
3359 llvm_unreachable("Invalid EntityKind!")::llvm::llvm_unreachable_internal("Invalid EntityKind!", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3359)
;
3360}
3361
3362bool InitializedEntity::allowsNRVO() const {
3363 switch (getKind()) {
3364 case EK_Result:
3365 case EK_Exception:
3366 return LocAndNRVO.NRVO;
3367
3368 case EK_StmtExprResult:
3369 case EK_Variable:
3370 case EK_Parameter:
3371 case EK_Parameter_CF_Audited:
3372 case EK_TemplateParameter:
3373 case EK_Member:
3374 case EK_Binding:
3375 case EK_New:
3376 case EK_Temporary:
3377 case EK_CompoundLiteralInit:
3378 case EK_Base:
3379 case EK_Delegating:
3380 case EK_ArrayElement:
3381 case EK_VectorElement:
3382 case EK_ComplexElement:
3383 case EK_BlockElement:
3384 case EK_LambdaToBlockConversionBlockElement:
3385 case EK_LambdaCapture:
3386 case EK_RelatedResult:
3387 break;
3388 }
3389
3390 return false;
3391}
3392
3393unsigned InitializedEntity::dumpImpl(raw_ostream &OS) const {
3394 assert(getParent() != this)((getParent() != this) ? static_cast<void> (0) : __assert_fail
("getParent() != this", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3394, __PRETTY_FUNCTION__))
;
3395 unsigned Depth = getParent() ? getParent()->dumpImpl(OS) : 0;
3396 for (unsigned I = 0; I != Depth; ++I)
3397 OS << "`-";
3398
3399 switch (getKind()) {
3400 case EK_Variable: OS << "Variable"; break;
3401 case EK_Parameter: OS << "Parameter"; break;
3402 case EK_Parameter_CF_Audited: OS << "CF audited function Parameter";
3403 break;
3404 case EK_TemplateParameter: OS << "TemplateParameter"; break;
3405 case EK_Result: OS << "Result"; break;
3406 case EK_StmtExprResult: OS << "StmtExprResult"; break;
3407 case EK_Exception: OS << "Exception"; break;
3408 case EK_Member: OS << "Member"; break;
3409 case EK_Binding: OS << "Binding"; break;
3410 case EK_New: OS << "New"; break;
3411 case EK_Temporary: OS << "Temporary"; break;
3412 case EK_CompoundLiteralInit: OS << "CompoundLiteral";break;
3413 case EK_RelatedResult: OS << "RelatedResult"; break;
3414 case EK_Base: OS << "Base"; break;
3415 case EK_Delegating: OS << "Delegating"; break;
3416 case EK_ArrayElement: OS << "ArrayElement " << Index; break;
3417 case EK_VectorElement: OS << "VectorElement " << Index; break;
3418 case EK_ComplexElement: OS << "ComplexElement " << Index; break;
3419 case EK_BlockElement: OS << "Block"; break;
3420 case EK_LambdaToBlockConversionBlockElement:
3421 OS << "Block (lambda)";
3422 break;
3423 case EK_LambdaCapture:
3424 OS << "LambdaCapture ";
3425 OS << DeclarationName(Capture.VarID);
3426 break;
3427 }
3428
3429 if (auto *D = getDecl()) {
3430 OS << " ";
3431 D->printQualifiedName(OS);
3432 }
3433
3434 OS << " '" << getType().getAsString() << "'\n";
3435
3436 return Depth + 1;
3437}
3438
3439LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void InitializedEntity::dump() const {
3440 dumpImpl(llvm::errs());
3441}
3442
3443//===----------------------------------------------------------------------===//
3444// Initialization sequence
3445//===----------------------------------------------------------------------===//
3446
3447void InitializationSequence::Step::Destroy() {
3448 switch (Kind) {
3449 case SK_ResolveAddressOfOverloadedFunction:
3450 case SK_CastDerivedToBaseRValue:
3451 case SK_CastDerivedToBaseXValue:
3452 case SK_CastDerivedToBaseLValue:
3453 case SK_BindReference:
3454 case SK_BindReferenceToTemporary:
3455 case SK_FinalCopy:
3456 case SK_ExtraneousCopyToTemporary:
3457 case SK_UserConversion:
3458 case SK_QualificationConversionRValue:
3459 case SK_QualificationConversionXValue:
3460 case SK_QualificationConversionLValue:
3461 case SK_FunctionReferenceConversion:
3462 case SK_AtomicConversion:
3463 case SK_ListInitialization:
3464 case SK_UnwrapInitList:
3465 case SK_RewrapInitList:
3466 case SK_ConstructorInitialization:
3467 case SK_ConstructorInitializationFromList:
3468 case SK_ZeroInitialization:
3469 case SK_CAssignment:
3470 case SK_StringInit:
3471 case SK_ObjCObjectConversion:
3472 case SK_ArrayLoopIndex:
3473 case SK_ArrayLoopInit:
3474 case SK_ArrayInit:
3475 case SK_GNUArrayInit:
3476 case SK_ParenthesizedArrayInit:
3477 case SK_PassByIndirectCopyRestore:
3478 case SK_PassByIndirectRestore:
3479 case SK_ProduceObjCObject:
3480 case SK_StdInitializerList:
3481 case SK_StdInitializerListConstructorCall:
3482 case SK_OCLSamplerInit:
3483 case SK_OCLZeroOpaqueType:
3484 break;
3485
3486 case SK_ConversionSequence:
3487 case SK_ConversionSequenceNoNarrowing:
3488 delete ICS;
3489 }
3490}
3491
3492bool InitializationSequence::isDirectReferenceBinding() const {
3493 // There can be some lvalue adjustments after the SK_BindReference step.
3494 for (auto I = Steps.rbegin(); I != Steps.rend(); ++I) {
3495 if (I->Kind == SK_BindReference)
3496 return true;
3497 if (I->Kind == SK_BindReferenceToTemporary)
3498 return false;
3499 }
3500 return false;
3501}
3502
3503bool InitializationSequence::isAmbiguous() const {
3504 if (!Failed())
3505 return false;
3506
3507 switch (getFailureKind()) {
3508 case FK_TooManyInitsForReference:
3509 case FK_ParenthesizedListInitForReference:
3510 case FK_ArrayNeedsInitList:
3511 case FK_ArrayNeedsInitListOrStringLiteral:
3512 case FK_ArrayNeedsInitListOrWideStringLiteral:
3513 case FK_NarrowStringIntoWideCharArray:
3514 case FK_WideStringIntoCharArray:
3515 case FK_IncompatWideStringIntoWideChar:
3516 case FK_PlainStringIntoUTF8Char:
3517 case FK_UTF8StringIntoPlainChar:
3518 case FK_AddressOfOverloadFailed: // FIXME: Could do better
3519 case FK_NonConstLValueReferenceBindingToTemporary:
3520 case FK_NonConstLValueReferenceBindingToBitfield:
3521 case FK_NonConstLValueReferenceBindingToVectorElement:
3522 case FK_NonConstLValueReferenceBindingToMatrixElement:
3523 case FK_NonConstLValueReferenceBindingToUnrelated:
3524 case FK_RValueReferenceBindingToLValue:
3525 case FK_ReferenceAddrspaceMismatchTemporary:
3526 case FK_ReferenceInitDropsQualifiers:
3527 case FK_ReferenceInitFailed:
3528 case FK_ConversionFailed:
3529 case FK_ConversionFromPropertyFailed:
3530 case FK_TooManyInitsForScalar:
3531 case FK_ParenthesizedListInitForScalar:
3532 case FK_ReferenceBindingToInitList:
3533 case FK_InitListBadDestinationType:
3534 case FK_DefaultInitOfConst:
3535 case FK_Incomplete:
3536 case FK_ArrayTypeMismatch:
3537 case FK_NonConstantArrayInit:
3538 case FK_ListInitializationFailed:
3539 case FK_VariableLengthArrayHasInitializer:
3540 case FK_PlaceholderType:
3541 case FK_ExplicitConstructor:
3542 case FK_AddressOfUnaddressableFunction:
3543 return false;
3544
3545 case FK_ReferenceInitOverloadFailed:
3546 case FK_UserConversionOverloadFailed:
3547 case FK_ConstructorOverloadFailed:
3548 case FK_ListConstructorOverloadFailed:
3549 return FailedOverloadResult == OR_Ambiguous;
3550 }
3551
3552 llvm_unreachable("Invalid EntityKind!")::llvm::llvm_unreachable_internal("Invalid EntityKind!", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3552)
;
3553}
3554
3555bool InitializationSequence::isConstructorInitialization() const {
3556 return !Steps.empty() && Steps.back().Kind == SK_ConstructorInitialization;
3557}
3558
3559void
3560InitializationSequence
3561::AddAddressOverloadResolutionStep(FunctionDecl *Function,
3562 DeclAccessPair Found,
3563 bool HadMultipleCandidates) {
3564 Step S;
3565 S.Kind = SK_ResolveAddressOfOverloadedFunction;
3566 S.Type = Function->getType();
3567 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3568 S.Function.Function = Function;
3569 S.Function.FoundDecl = Found;
3570 Steps.push_back(S);
3571}
3572
3573void InitializationSequence::AddDerivedToBaseCastStep(QualType BaseType,
3574 ExprValueKind VK) {
3575 Step S;
3576 switch (VK) {
3577 case VK_RValue: S.Kind = SK_CastDerivedToBaseRValue; break;
3578 case VK_XValue: S.Kind = SK_CastDerivedToBaseXValue; break;
3579 case VK_LValue: S.Kind = SK_CastDerivedToBaseLValue; break;
3580 }
3581 S.Type = BaseType;
3582 Steps.push_back(S);
3583}
3584
3585void InitializationSequence::AddReferenceBindingStep(QualType T,
3586 bool BindingTemporary) {
3587 Step S;
3588 S.Kind = BindingTemporary? SK_BindReferenceToTemporary : SK_BindReference;
3589 S.Type = T;
3590 Steps.push_back(S);
3591}
3592
3593void InitializationSequence::AddFinalCopy(QualType T) {
3594 Step S;
3595 S.Kind = SK_FinalCopy;
3596 S.Type = T;
3597 Steps.push_back(S);
3598}
3599
3600void InitializationSequence::AddExtraneousCopyToTemporary(QualType T) {
3601 Step S;
3602 S.Kind = SK_ExtraneousCopyToTemporary;
3603 S.Type = T;
3604 Steps.push_back(S);
3605}
3606
3607void
3608InitializationSequence::AddUserConversionStep(FunctionDecl *Function,
3609 DeclAccessPair FoundDecl,
3610 QualType T,
3611 bool HadMultipleCandidates) {
3612 Step S;
3613 S.Kind = SK_UserConversion;
3614 S.Type = T;
3615 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3616 S.Function.Function = Function;
3617 S.Function.FoundDecl = FoundDecl;
3618 Steps.push_back(S);
3619}
3620
3621void InitializationSequence::AddQualificationConversionStep(QualType Ty,
3622 ExprValueKind VK) {
3623 Step S;
3624 S.Kind = SK_QualificationConversionRValue; // work around a gcc warning
3625 switch (VK) {
3626 case VK_RValue:
3627 S.Kind = SK_QualificationConversionRValue;
3628 break;
3629 case VK_XValue:
3630 S.Kind = SK_QualificationConversionXValue;
3631 break;
3632 case VK_LValue:
3633 S.Kind = SK_QualificationConversionLValue;
3634 break;
3635 }
3636 S.Type = Ty;
3637 Steps.push_back(S);
3638}
3639
3640void InitializationSequence::AddFunctionReferenceConversionStep(QualType Ty) {
3641 Step S;
3642 S.Kind = SK_FunctionReferenceConversion;
3643 S.Type = Ty;
3644 Steps.push_back(S);
3645}
3646
3647void InitializationSequence::AddAtomicConversionStep(QualType Ty) {
3648 Step S;
3649 S.Kind = SK_AtomicConversion;
3650 S.Type = Ty;
3651 Steps.push_back(S);
3652}
3653
3654void InitializationSequence::AddConversionSequenceStep(
3655 const ImplicitConversionSequence &ICS, QualType T,
3656 bool TopLevelOfInitList) {
3657 Step S;
3658 S.Kind = TopLevelOfInitList ? SK_ConversionSequenceNoNarrowing
3659 : SK_ConversionSequence;
3660 S.Type = T;
3661 S.ICS = new ImplicitConversionSequence(ICS);
3662 Steps.push_back(S);
3663}
3664
3665void InitializationSequence::AddListInitializationStep(QualType T) {
3666 Step S;
3667 S.Kind = SK_ListInitialization;
3668 S.Type = T;
3669 Steps.push_back(S);
3670}
3671
3672void InitializationSequence::AddConstructorInitializationStep(
3673 DeclAccessPair FoundDecl, CXXConstructorDecl *Constructor, QualType T,
3674 bool HadMultipleCandidates, bool FromInitList, bool AsInitList) {
3675 Step S;
3676 S.Kind = FromInitList ? AsInitList ? SK_StdInitializerListConstructorCall
3677 : SK_ConstructorInitializationFromList
3678 : SK_ConstructorInitialization;
3679 S.Type = T;
3680 S.Function.HadMultipleCandidates = HadMultipleCandidates;
3681 S.Function.Function = Constructor;
3682 S.Function.FoundDecl = FoundDecl;
3683 Steps.push_back(S);
3684}
3685
3686void InitializationSequence::AddZeroInitializationStep(QualType T) {
3687 Step S;
3688 S.Kind = SK_ZeroInitialization;
3689 S.Type = T;
3690 Steps.push_back(S);
3691}
3692
3693void InitializationSequence::AddCAssignmentStep(QualType T) {
3694 Step S;
3695 S.Kind = SK_CAssignment;
3696 S.Type = T;
3697 Steps.push_back(S);
3698}
3699
3700void InitializationSequence::AddStringInitStep(QualType T) {
3701 Step S;
3702 S.Kind = SK_StringInit;
3703 S.Type = T;
3704 Steps.push_back(S);
3705}
3706
3707void InitializationSequence::AddObjCObjectConversionStep(QualType T) {
3708 Step S;
3709 S.Kind = SK_ObjCObjectConversion;
3710 S.Type = T;
3711 Steps.push_back(S);
3712}
3713
3714void InitializationSequence::AddArrayInitStep(QualType T, bool IsGNUExtension) {
3715 Step S;
3716 S.Kind = IsGNUExtension ? SK_GNUArrayInit : SK_ArrayInit;
3717 S.Type = T;
3718 Steps.push_back(S);
3719}
3720
3721void InitializationSequence::AddArrayInitLoopStep(QualType T, QualType EltT) {
3722 Step S;
3723 S.Kind = SK_ArrayLoopIndex;
3724 S.Type = EltT;
3725 Steps.insert(Steps.begin(), S);
3726
3727 S.Kind = SK_ArrayLoopInit;
3728 S.Type = T;
3729 Steps.push_back(S);
3730}
3731
3732void InitializationSequence::AddParenthesizedArrayInitStep(QualType T) {
3733 Step S;
3734 S.Kind = SK_ParenthesizedArrayInit;
3735 S.Type = T;
3736 Steps.push_back(S);
3737}
3738
3739void InitializationSequence::AddPassByIndirectCopyRestoreStep(QualType type,
3740 bool shouldCopy) {
3741 Step s;
3742 s.Kind = (shouldCopy ? SK_PassByIndirectCopyRestore
3743 : SK_PassByIndirectRestore);
3744 s.Type = type;
3745 Steps.push_back(s);
3746}
3747
3748void InitializationSequence::AddProduceObjCObjectStep(QualType T) {
3749 Step S;
3750 S.Kind = SK_ProduceObjCObject;
3751 S.Type = T;
3752 Steps.push_back(S);
3753}
3754
3755void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) {
3756 Step S;
3757 S.Kind = SK_StdInitializerList;
3758 S.Type = T;
3759 Steps.push_back(S);
3760}
3761
3762void InitializationSequence::AddOCLSamplerInitStep(QualType T) {
3763 Step S;
3764 S.Kind = SK_OCLSamplerInit;
3765 S.Type = T;
3766 Steps.push_back(S);
3767}
3768
3769void InitializationSequence::AddOCLZeroOpaqueTypeStep(QualType T) {
3770 Step S;
3771 S.Kind = SK_OCLZeroOpaqueType;
3772 S.Type = T;
3773 Steps.push_back(S);
3774}
3775
3776void InitializationSequence::RewrapReferenceInitList(QualType T,
3777 InitListExpr *Syntactic) {
3778 assert(Syntactic->getNumInits() == 1 &&((Syntactic->getNumInits() == 1 && "Can only rewrap trivial init lists."
) ? static_cast<void> (0) : __assert_fail ("Syntactic->getNumInits() == 1 && \"Can only rewrap trivial init lists.\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3779, __PRETTY_FUNCTION__))
3779 "Can only rewrap trivial init lists.")((Syntactic->getNumInits() == 1 && "Can only rewrap trivial init lists."
) ? static_cast<void> (0) : __assert_fail ("Syntactic->getNumInits() == 1 && \"Can only rewrap trivial init lists.\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3779, __PRETTY_FUNCTION__))
;
3780 Step S;
3781 S.Kind = SK_UnwrapInitList;
3782 S.Type = Syntactic->getInit(0)->getType();
3783 Steps.insert(Steps.begin(), S);
3784
3785 S.Kind = SK_RewrapInitList;
3786 S.Type = T;
3787 S.WrappingSyntacticList = Syntactic;
3788 Steps.push_back(S);
3789}
3790
3791void InitializationSequence::SetOverloadFailure(FailureKind Failure,
3792 OverloadingResult Result) {
3793 setSequenceKind(FailedSequence);
3794 this->Failure = Failure;
3795 this->FailedOverloadResult = Result;
3796}
3797
3798//===----------------------------------------------------------------------===//
3799// Attempt initialization
3800//===----------------------------------------------------------------------===//
3801
3802/// Tries to add a zero initializer. Returns true if that worked.
3803static bool
3804maybeRecoverWithZeroInitialization(Sema &S, InitializationSequence &Sequence,
3805 const InitializedEntity &Entity) {
3806 if (Entity.getKind() != InitializedEntity::EK_Variable)
3807 return false;
3808
3809 VarDecl *VD = cast<VarDecl>(Entity.getDecl());
3810 if (VD->getInit() || VD->getEndLoc().isMacroID())
3811 return false;
3812
3813 QualType VariableTy = VD->getType().getCanonicalType();
3814 SourceLocation Loc = S.getLocForEndOfToken(VD->getEndLoc());
3815 std::string Init = S.getFixItZeroInitializerForType(VariableTy, Loc);
3816 if (!Init.empty()) {
3817 Sequence.AddZeroInitializationStep(Entity.getType());
3818 Sequence.SetZeroInitializationFixit(Init, Loc);
3819 return true;
3820 }
3821 return false;
3822}
3823
3824static void MaybeProduceObjCObject(Sema &S,
3825 InitializationSequence &Sequence,
3826 const InitializedEntity &Entity) {
3827 if (!S.getLangOpts().ObjCAutoRefCount) return;
3828
3829 /// When initializing a parameter, produce the value if it's marked
3830 /// __attribute__((ns_consumed)).
3831 if (Entity.isParameterKind()) {
3832 if (!Entity.isParameterConsumed())
3833 return;
3834
3835 assert(Entity.getType()->isObjCRetainableType() &&((Entity.getType()->isObjCRetainableType() && "consuming an object of unretainable type?"
) ? static_cast<void> (0) : __assert_fail ("Entity.getType()->isObjCRetainableType() && \"consuming an object of unretainable type?\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3836, __PRETTY_FUNCTION__))
3836 "consuming an object of unretainable type?")((Entity.getType()->isObjCRetainableType() && "consuming an object of unretainable type?"
) ? static_cast<void> (0) : __assert_fail ("Entity.getType()->isObjCRetainableType() && \"consuming an object of unretainable type?\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 3836, __PRETTY_FUNCTION__))
;
3837 Sequence.AddProduceObjCObjectStep(Entity.getType());
3838
3839 /// When initializing a return value, if the return type is a
3840 /// retainable type, then returns need to immediately retain the
3841 /// object. If an autorelease is required, it will be done at the
3842 /// last instant.
3843 } else if (Entity.getKind() == InitializedEntity::EK_Result ||
3844 Entity.getKind() == InitializedEntity::EK_StmtExprResult) {
3845 if (!Entity.getType()->isObjCRetainableType())
3846 return;
3847
3848 Sequence.AddProduceObjCObjectStep(Entity.getType());
3849 }
3850}
3851
3852static void TryListInitialization(Sema &S,
3853 const InitializedEntity &Entity,
3854 const InitializationKind &Kind,
3855 InitListExpr *InitList,
3856 InitializationSequence &Sequence,
3857 bool TreatUnavailableAsInvalid);
3858
3859/// When initializing from init list via constructor, handle
3860/// initialization of an object of type std::initializer_list<T>.
3861///
3862/// \return true if we have handled initialization of an object of type
3863/// std::initializer_list<T>, false otherwise.
3864static bool TryInitializerListConstruction(Sema &S,
3865 InitListExpr *List,
3866 QualType DestType,
3867 InitializationSequence &Sequence,
3868 bool TreatUnavailableAsInvalid) {
3869 QualType E;
3870 if (!S.isStdInitializerList(DestType, &E))
3871 return false;
3872
3873 if (!S.isCompleteType(List->getExprLoc(), E)) {
3874 Sequence.setIncompleteTypeFailure(E);
3875 return true;
3876 }
3877
3878 // Try initializing a temporary array from the init list.
3879 QualType ArrayType = S.Context.getConstantArrayType(
3880 E.withConst(),
3881 llvm::APInt(S.Context.getTypeSize(S.Context.getSizeType()),
3882 List->getNumInits()),
3883 nullptr, clang::ArrayType::Normal, 0);
3884 InitializedEntity HiddenArray =
3885 InitializedEntity::InitializeTemporary(ArrayType);
3886 InitializationKind Kind = InitializationKind::CreateDirectList(
3887 List->getExprLoc(), List->getBeginLoc(), List->getEndLoc());
3888 TryListInitialization(S, HiddenArray, Kind, List, Sequence,
3889 TreatUnavailableAsInvalid);
3890 if (Sequence)
3891 Sequence.AddStdInitializerListConstructionStep(DestType);
3892 return true;
3893}
3894
3895/// Determine if the constructor has the signature of a copy or move
3896/// constructor for the type T of the class in which it was found. That is,
3897/// determine if its first parameter is of type T or reference to (possibly
3898/// cv-qualified) T.
3899static bool hasCopyOrMoveCtorParam(ASTContext &Ctx,
3900 const ConstructorInfo &Info) {
3901 if (Info.Constructor->getNumParams() == 0)
3902 return false;
3903
3904 QualType ParmT =
3905 Info.Constructor->getParamDecl(0)->getType().getNonReferenceType();
3906 QualType ClassT =
3907 Ctx.getRecordType(cast<CXXRecordDecl>(Info.FoundDecl->getDeclContext()));
3908
3909 return Ctx.hasSameUnqualifiedType(ParmT, ClassT);
3910}
3911
3912static OverloadingResult
3913ResolveConstructorOverload(Sema &S, SourceLocation DeclLoc,
3914 MultiExprArg Args,
3915 OverloadCandidateSet &CandidateSet,
3916 QualType DestType,
3917 DeclContext::lookup_result Ctors,
3918 OverloadCandidateSet::iterator &Best,
3919 bool CopyInitializing, bool AllowExplicit,
3920 bool OnlyListConstructors, bool IsListInit,
3921 bool SecondStepOfCopyInit = false) {
3922 CandidateSet.clear(OverloadCandidateSet::CSK_InitByConstructor);
3923 CandidateSet.setDestAS(DestType.getQualifiers().getAddressSpace());
3924
3925 for (NamedDecl *D : Ctors) {
3926 auto Info = getConstructorInfo(D);
3927 if (!Info.Constructor || Info.Constructor->isInvalidDecl())
3928 continue;
3929
3930 if (OnlyListConstructors && !S.isInitListConstructor(Info.Constructor))
3931 continue;
3932
3933 // C++11 [over.best.ics]p4:
3934 // ... and the constructor or user-defined conversion function is a
3935 // candidate by
3936 // - 13.3.1.3, when the argument is the temporary in the second step
3937 // of a class copy-initialization, or
3938 // - 13.3.1.4, 13.3.1.5, or 13.3.1.6 (in all cases), [not handled here]
3939 // - the second phase of 13.3.1.7 when the initializer list has exactly
3940 // one element that is itself an initializer list, and the target is
3941 // the first parameter of a constructor of class X, and the conversion
3942 // is to X or reference to (possibly cv-qualified X),
3943 // user-defined conversion sequences are not considered.
3944 bool SuppressUserConversions =
3945 SecondStepOfCopyInit ||
3946 (IsListInit && Args.size() == 1 && isa<InitListExpr>(Args[0]) &&
3947 hasCopyOrMoveCtorParam(S.Context, Info));
3948
3949 if (Info.ConstructorTmpl)
3950 S.AddTemplateOverloadCandidate(
3951 Info.ConstructorTmpl, Info.FoundDecl,
3952 /*ExplicitArgs*/ nullptr, Args, CandidateSet, SuppressUserConversions,
3953 /*PartialOverloading=*/false, AllowExplicit);
3954 else {
3955 // C++ [over.match.copy]p1:
3956 // - When initializing a temporary to be bound to the first parameter
3957 // of a constructor [for type T] that takes a reference to possibly
3958 // cv-qualified T as its first argument, called with a single
3959 // argument in the context of direct-initialization, explicit
3960 // conversion functions are also considered.
3961 // FIXME: What if a constructor template instantiates to such a signature?
3962 bool AllowExplicitConv = AllowExplicit && !CopyInitializing &&
3963 Args.size() == 1 &&
3964 hasCopyOrMoveCtorParam(S.Context, Info);
3965 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl, Args,
3966 CandidateSet, SuppressUserConversions,
3967 /*PartialOverloading=*/false, AllowExplicit,
3968 AllowExplicitConv);
3969 }
3970 }
3971
3972 // FIXME: Work around a bug in C++17 guaranteed copy elision.
3973 //
3974 // When initializing an object of class type T by constructor
3975 // ([over.match.ctor]) or by list-initialization ([over.match.list])
3976 // from a single expression of class type U, conversion functions of
3977 // U that convert to the non-reference type cv T are candidates.
3978 // Explicit conversion functions are only candidates during
3979 // direct-initialization.
3980 //
3981 // Note: SecondStepOfCopyInit is only ever true in this case when
3982 // evaluating whether to produce a C++98 compatibility warning.
3983 if (S.getLangOpts().CPlusPlus17 && Args.size() == 1 &&
3984 !SecondStepOfCopyInit) {
3985 Expr *Initializer = Args[0];
3986 auto *SourceRD = Initializer->getType()->getAsCXXRecordDecl();
3987 if (SourceRD && S.isCompleteType(DeclLoc, Initializer->getType())) {
3988 const auto &Conversions = SourceRD->getVisibleConversionFunctions();
3989 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
3990 NamedDecl *D = *I;
3991 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
3992 D = D->getUnderlyingDecl();
3993
3994 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
3995 CXXConversionDecl *Conv;
3996 if (ConvTemplate)
3997 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
3998 else
3999 Conv = cast<CXXConversionDecl>(D);
4000
4001 if (ConvTemplate)
4002 S.AddTemplateConversionCandidate(
4003 ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
4004 CandidateSet, AllowExplicit, AllowExplicit,
4005 /*AllowResultConversion*/ false);
4006 else
4007 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Initializer,
4008 DestType, CandidateSet, AllowExplicit,
4009 AllowExplicit,
4010 /*AllowResultConversion*/ false);
4011 }
4012 }
4013 }
4014
4015 // Perform overload resolution and return the result.
4016 return CandidateSet.BestViableFunction(S, DeclLoc, Best);
4017}
4018
4019/// Attempt initialization by constructor (C++ [dcl.init]), which
4020/// enumerates the constructors of the initialized entity and performs overload
4021/// resolution to select the best.
4022/// \param DestType The destination class type.
4023/// \param DestArrayType The destination type, which is either DestType or
4024/// a (possibly multidimensional) array of DestType.
4025/// \param IsListInit Is this list-initialization?
4026/// \param IsInitListCopy Is this non-list-initialization resulting from a
4027/// list-initialization from {x} where x is the same
4028/// type as the entity?
4029static void TryConstructorInitialization(Sema &S,
4030 const InitializedEntity &Entity,
4031 const InitializationKind &Kind,
4032 MultiExprArg Args, QualType DestType,
4033 QualType DestArrayType,
4034 InitializationSequence &Sequence,
4035 bool IsListInit = false,
4036 bool IsInitListCopy = false) {
4037 assert(((!IsListInit && !IsInitListCopy) ||((((!IsListInit && !IsInitListCopy) || (Args.size() ==
1 && isa<InitListExpr>(Args[0]))) && "IsListInit/IsInitListCopy must come with a single initializer list "
"argument.") ? static_cast<void> (0) : __assert_fail (
"((!IsListInit && !IsInitListCopy) || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && \"IsListInit/IsInitListCopy must come with a single initializer list \" \"argument.\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4040, __PRETTY_FUNCTION__))
4038 (Args.size() == 1 && isa<InitListExpr>(Args[0]))) &&((((!IsListInit && !IsInitListCopy) || (Args.size() ==
1 && isa<InitListExpr>(Args[0]))) && "IsListInit/IsInitListCopy must come with a single initializer list "
"argument.") ? static_cast<void> (0) : __assert_fail (
"((!IsListInit && !IsInitListCopy) || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && \"IsListInit/IsInitListCopy must come with a single initializer list \" \"argument.\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4040, __PRETTY_FUNCTION__))
4039 "IsListInit/IsInitListCopy must come with a single initializer list "((((!IsListInit && !IsInitListCopy) || (Args.size() ==
1 && isa<InitListExpr>(Args[0]))) && "IsListInit/IsInitListCopy must come with a single initializer list "
"argument.") ? static_cast<void> (0) : __assert_fail (
"((!IsListInit && !IsInitListCopy) || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && \"IsListInit/IsInitListCopy must come with a single initializer list \" \"argument.\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4040, __PRETTY_FUNCTION__))
4040 "argument.")((((!IsListInit && !IsInitListCopy) || (Args.size() ==
1 && isa<InitListExpr>(Args[0]))) && "IsListInit/IsInitListCopy must come with a single initializer list "
"argument.") ? static_cast<void> (0) : __assert_fail (
"((!IsListInit && !IsInitListCopy) || (Args.size() == 1 && isa<InitListExpr>(Args[0]))) && \"IsListInit/IsInitListCopy must come with a single initializer list \" \"argument.\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4040, __PRETTY_FUNCTION__))
;
4041 InitListExpr *ILE =
4042 (IsListInit || IsInitListCopy) ? cast<InitListExpr>(Args[0]) : nullptr;
4043 MultiExprArg UnwrappedArgs =
4044 ILE ? MultiExprArg(ILE->getInits(), ILE->getNumInits()) : Args;
4045
4046 // The type we're constructing needs to be complete.
4047 if (!S.isCompleteType(Kind.getLocation(), DestType)) {
4048 Sequence.setIncompleteTypeFailure(DestType);
4049 return;
4050 }
4051
4052 // C++17 [dcl.init]p17:
4053 // - If the initializer expression is a prvalue and the cv-unqualified
4054 // version of the source type is the same class as the class of the
4055 // destination, the initializer expression is used to initialize the
4056 // destination object.
4057 // Per DR (no number yet), this does not apply when initializing a base
4058 // class or delegating to another constructor from a mem-initializer.
4059 // ObjC++: Lambda captured by the block in the lambda to block conversion
4060 // should avoid copy elision.
4061 if (S.getLangOpts().CPlusPlus17 &&
4062 Entity.getKind() != InitializedEntity::EK_Base &&
4063 Entity.getKind() != InitializedEntity::EK_Delegating &&
4064 Entity.getKind() !=
4065 InitializedEntity::EK_LambdaToBlockConversionBlockElement &&
4066 UnwrappedArgs.size() == 1 && UnwrappedArgs[0]->isRValue() &&
4067 S.Context.hasSameUnqualifiedType(UnwrappedArgs[0]->getType(), DestType)) {
4068 // Convert qualifications if necessary.
4069 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
4070 if (ILE)
4071 Sequence.RewrapReferenceInitList(DestType, ILE);
4072 return;
4073 }
4074
4075 const RecordType *DestRecordType = DestType->getAs<RecordType>();
4076 assert(DestRecordType && "Constructor initialization requires record type")((DestRecordType && "Constructor initialization requires record type"
) ? static_cast<void> (0) : __assert_fail ("DestRecordType && \"Constructor initialization requires record type\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4076, __PRETTY_FUNCTION__))
;
4077 CXXRecordDecl *DestRecordDecl
4078 = cast<CXXRecordDecl>(DestRecordType->getDecl());
4079
4080 // Build the candidate set directly in the initialization sequence
4081 // structure, so that it will persist if we fail.
4082 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4083
4084 // Determine whether we are allowed to call explicit constructors or
4085 // explicit conversion operators.
4086 bool AllowExplicit = Kind.AllowExplicit() || IsListInit;
4087 bool CopyInitialization = Kind.getKind() == InitializationKind::IK_Copy;
4088
4089 // - Otherwise, if T is a class type, constructors are considered. The
4090 // applicable constructors are enumerated, and the best one is chosen
4091 // through overload resolution.
4092 DeclContext::lookup_result Ctors = S.LookupConstructors(DestRecordDecl);
4093
4094 OverloadingResult Result = OR_No_Viable_Function;
4095 OverloadCandidateSet::iterator Best;
4096 bool AsInitializerList = false;
4097
4098 // C++11 [over.match.list]p1, per DR1467:
4099 // When objects of non-aggregate type T are list-initialized, such that
4100 // 8.5.4 [dcl.init.list] specifies that overload resolution is performed
4101 // according to the rules in this section, overload resolution selects
4102 // the constructor in two phases:
4103 //
4104 // - Initially, the candidate functions are the initializer-list
4105 // constructors of the class T and the argument list consists of the
4106 // initializer list as a single argument.
4107 if (IsListInit) {
4108 AsInitializerList = true;
4109
4110 // If the initializer list has no elements and T has a default constructor,
4111 // the first phase is omitted.
4112 if (!(UnwrappedArgs.empty() && S.LookupDefaultConstructor(DestRecordDecl)))
4113 Result = ResolveConstructorOverload(S, Kind.getLocation(), Args,
4114 CandidateSet, DestType, Ctors, Best,
4115 CopyInitialization, AllowExplicit,
4116 /*OnlyListConstructors=*/true,
4117 IsListInit);
4118 }
4119
4120 // C++11 [over.match.list]p1:
4121 // - If no viable initializer-list constructor is found, overload resolution
4122 // is performed again, where the candidate functions are all the
4123 // constructors of the class T and the argument list consists of the
4124 // elements of the initializer list.
4125 if (Result == OR_No_Viable_Function) {
4126 AsInitializerList = false;
4127 Result = ResolveConstructorOverload(S, Kind.getLocation(), UnwrappedArgs,
4128 CandidateSet, DestType, Ctors, Best,
4129 CopyInitialization, AllowExplicit,
4130 /*OnlyListConstructors=*/false,
4131 IsListInit);
4132 }
4133 if (Result) {
4134 Sequence.SetOverloadFailure(
4135 IsListInit ? InitializationSequence::FK_ListConstructorOverloadFailed
4136 : InitializationSequence::FK_ConstructorOverloadFailed,
4137 Result);
4138
4139 if (Result != OR_Deleted)
4140 return;
4141 }
4142
4143 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4144
4145 // In C++17, ResolveConstructorOverload can select a conversion function
4146 // instead of a constructor.
4147 if (auto *CD = dyn_cast<CXXConversionDecl>(Best->Function)) {
4148 // Add the user-defined conversion step that calls the conversion function.
4149 QualType ConvType = CD->getConversionType();
4150 assert(S.Context.hasSameUnqualifiedType(ConvType, DestType) &&((S.Context.hasSameUnqualifiedType(ConvType, DestType) &&
"should not have selected this conversion function") ? static_cast
<void> (0) : __assert_fail ("S.Context.hasSameUnqualifiedType(ConvType, DestType) && \"should not have selected this conversion function\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4151, __PRETTY_FUNCTION__))
4151 "should not have selected this conversion function")((S.Context.hasSameUnqualifiedType(ConvType, DestType) &&
"should not have selected this conversion function") ? static_cast
<void> (0) : __assert_fail ("S.Context.hasSameUnqualifiedType(ConvType, DestType) && \"should not have selected this conversion function\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4151, __PRETTY_FUNCTION__))
;
4152 Sequence.AddUserConversionStep(CD, Best->FoundDecl, ConvType,
4153 HadMultipleCandidates);
4154 if (!S.Context.hasSameType(ConvType, DestType))
4155 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
4156 if (IsListInit)
4157 Sequence.RewrapReferenceInitList(Entity.getType(), ILE);
4158 return;
4159 }
4160
4161 CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
4162 if (Result != OR_Deleted) {
4163 // C++11 [dcl.init]p6:
4164 // If a program calls for the default initialization of an object
4165 // of a const-qualified type T, T shall be a class type with a
4166 // user-provided default constructor.
4167 // C++ core issue 253 proposal:
4168 // If the implicit default constructor initializes all subobjects, no
4169 // initializer should be required.
4170 // The 253 proposal is for example needed to process libstdc++ headers
4171 // in 5.x.
4172 if (Kind.getKind() == InitializationKind::IK_Default &&
4173 Entity.getType().isConstQualified()) {
4174 if (!CtorDecl->getParent()->allowConstDefaultInit()) {
4175 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
4176 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
4177 return;
4178 }
4179 }
4180
4181 // C++11 [over.match.list]p1:
4182 // In copy-list-initialization, if an explicit constructor is chosen, the
4183 // initializer is ill-formed.
4184 if (IsListInit && !Kind.AllowExplicit() && CtorDecl->isExplicit()) {
4185 Sequence.SetFailed(InitializationSequence::FK_ExplicitConstructor);
4186 return;
4187 }
4188 }
4189
4190 // [class.copy.elision]p3:
4191 // In some copy-initialization contexts, a two-stage overload resolution
4192 // is performed.
4193 // If the first overload resolution selects a deleted function, we also
4194 // need the initialization sequence to decide whether to perform the second
4195 // overload resolution.
4196 // For deleted functions in other contexts, there is no need to get the
4197 // initialization sequence.
4198 if (Result == OR_Deleted && Kind.getKind() != InitializationKind::IK_Copy)
4199 return;
4200
4201 // Add the constructor initialization step. Any cv-qualification conversion is
4202 // subsumed by the initialization.
4203 Sequence.AddConstructorInitializationStep(
4204 Best->FoundDecl, CtorDecl, DestArrayType, HadMultipleCandidates,
4205 IsListInit | IsInitListCopy, AsInitializerList);
4206}
4207
4208static bool
4209ResolveOverloadedFunctionForReferenceBinding(Sema &S,
4210 Expr *Initializer,
4211 QualType &SourceType,
4212 QualType &UnqualifiedSourceType,
4213 QualType UnqualifiedTargetType,
4214 InitializationSequence &Sequence) {
4215 if (S.Context.getCanonicalType(UnqualifiedSourceType) ==
4216 S.Context.OverloadTy) {
4217 DeclAccessPair Found;
4218 bool HadMultipleCandidates = false;
4219 if (FunctionDecl *Fn
4220 = S.ResolveAddressOfOverloadedFunction(Initializer,
4221 UnqualifiedTargetType,
4222 false, Found,
4223 &HadMultipleCandidates)) {
4224 Sequence.AddAddressOverloadResolutionStep(Fn, Found,
4225 HadMultipleCandidates);
4226 SourceType = Fn->getType();
4227 UnqualifiedSourceType = SourceType.getUnqualifiedType();
4228 } else if (!UnqualifiedTargetType->isRecordType()) {
4229 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4230 return true;
4231 }
4232 }
4233 return false;
4234}
4235
4236static void TryReferenceInitializationCore(Sema &S,
4237 const InitializedEntity &Entity,
4238 const InitializationKind &Kind,
4239 Expr *Initializer,
4240 QualType cv1T1, QualType T1,
4241 Qualifiers T1Quals,
4242 QualType cv2T2, QualType T2,
4243 Qualifiers T2Quals,
4244 InitializationSequence &Sequence);
4245
4246static void TryValueInitialization(Sema &S,
4247 const InitializedEntity &Entity,
4248 const InitializationKind &Kind,
4249 InitializationSequence &Sequence,
4250 InitListExpr *InitList = nullptr);
4251
4252/// Attempt list initialization of a reference.
4253static void TryReferenceListInitialization(Sema &S,
4254 const InitializedEntity &Entity,
4255 const InitializationKind &Kind,
4256 InitListExpr *InitList,
4257 InitializationSequence &Sequence,
4258 bool TreatUnavailableAsInvalid) {
4259 // First, catch C++03 where this isn't possible.
4260 if (!S.getLangOpts().CPlusPlus11) {
4261 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
4262 return;
4263 }
4264 // Can't reference initialize a compound literal.
4265 if (Entity.getKind() == InitializedEntity::EK_CompoundLiteralInit) {
4266 Sequence.SetFailed(InitializationSequence::FK_ReferenceBindingToInitList);
4267 return;
4268 }
4269
4270 QualType DestType = Entity.getType();
4271 QualType cv1T1 = DestType->castAs<ReferenceType>()->getPointeeType();
4272 Qualifiers T1Quals;
4273 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
4274
4275 // Reference initialization via an initializer list works thus:
4276 // If the initializer list consists of a single element that is
4277 // reference-related to the referenced type, bind directly to that element
4278 // (possibly creating temporaries).
4279 // Otherwise, initialize a temporary with the initializer list and
4280 // bind to that.
4281 if (InitList->getNumInits() == 1) {
4282 Expr *Initializer = InitList->getInit(0);
4283 QualType cv2T2 = S.getCompletedType(Initializer);
4284 Qualifiers T2Quals;
4285 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
4286
4287 // If this fails, creating a temporary wouldn't work either.
4288 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
4289 T1, Sequence))
4290 return;
4291
4292 SourceLocation DeclLoc = Initializer->getBeginLoc();
4293 Sema::ReferenceCompareResult RefRelationship
4294 = S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2);
4295 if (RefRelationship >= Sema::Ref_Related) {
4296 // Try to bind the reference here.
4297 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
4298 T1Quals, cv2T2, T2, T2Quals, Sequence);
4299 if (Sequence)
4300 Sequence.RewrapReferenceInitList(cv1T1, InitList);
4301 return;
4302 }
4303
4304 // Update the initializer if we've resolved an overloaded function.
4305 if (Sequence.step_begin() != Sequence.step_end())
4306 Sequence.RewrapReferenceInitList(cv1T1, InitList);
4307 }
4308 // Perform address space compatibility check.
4309 QualType cv1T1IgnoreAS = cv1T1;
4310 if (T1Quals.hasAddressSpace()) {
4311 Qualifiers T2Quals;
4312 (void)S.Context.getUnqualifiedArrayType(InitList->getType(), T2Quals);
4313 if (!T1Quals.isAddressSpaceSupersetOf(T2Quals)) {
4314 Sequence.SetFailed(
4315 InitializationSequence::FK_ReferenceInitDropsQualifiers);
4316 return;
4317 }
4318 // Ignore address space of reference type at this point and perform address
4319 // space conversion after the reference binding step.
4320 cv1T1IgnoreAS =
4321 S.Context.getQualifiedType(T1, T1Quals.withoutAddressSpace());
4322 }
4323 // Not reference-related. Create a temporary and bind to that.
4324 InitializedEntity TempEntity =
4325 InitializedEntity::InitializeTemporary(cv1T1IgnoreAS);
4326
4327 TryListInitialization(S, TempEntity, Kind, InitList, Sequence,
4328 TreatUnavailableAsInvalid);
4329 if (Sequence) {
4330 if (DestType->isRValueReferenceType() ||
4331 (T1Quals.hasConst() && !T1Quals.hasVolatile())) {
4332 Sequence.AddReferenceBindingStep(cv1T1IgnoreAS,
4333 /*BindingTemporary=*/true);
4334 if (T1Quals.hasAddressSpace())
4335 Sequence.AddQualificationConversionStep(
4336 cv1T1, DestType->isRValueReferenceType() ? VK_XValue : VK_LValue);
4337 } else
4338 Sequence.SetFailed(
4339 InitializationSequence::FK_NonConstLValueReferenceBindingToTemporary);
4340 }
4341}
4342
4343/// Attempt list initialization (C++0x [dcl.init.list])
4344static void TryListInitialization(Sema &S,
4345 const InitializedEntity &Entity,
4346 const InitializationKind &Kind,
4347 InitListExpr *InitList,
4348 InitializationSequence &Sequence,
4349 bool TreatUnavailableAsInvalid) {
4350 QualType DestType = Entity.getType();
4351
4352 // C++ doesn't allow scalar initialization with more than one argument.
4353 // But C99 complex numbers are scalars and it makes sense there.
4354 if (S.getLangOpts().CPlusPlus && DestType->isScalarType() &&
4355 !DestType->isAnyComplexType() && InitList->getNumInits() > 1) {
4356 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForScalar);
4357 return;
4358 }
4359 if (DestType->isReferenceType()) {
4360 TryReferenceListInitialization(S, Entity, Kind, InitList, Sequence,
4361 TreatUnavailableAsInvalid);
4362 return;
4363 }
4364
4365 if (DestType->isRecordType() &&
4366 !S.isCompleteType(InitList->getBeginLoc(), DestType)) {
4367 Sequence.setIncompleteTypeFailure(DestType);
4368 return;
4369 }
4370
4371 // C++11 [dcl.init.list]p3, per DR1467:
4372 // - If T is a class type and the initializer list has a single element of
4373 // type cv U, where U is T or a class derived from T, the object is
4374 // initialized from that element (by copy-initialization for
4375 // copy-list-initialization, or by direct-initialization for
4376 // direct-list-initialization).
4377 // - Otherwise, if T is a character array and the initializer list has a
4378 // single element that is an appropriately-typed string literal
4379 // (8.5.2 [dcl.init.string]), initialization is performed as described
4380 // in that section.
4381 // - Otherwise, if T is an aggregate, [...] (continue below).
4382 if (S.getLangOpts().CPlusPlus11 && InitList->getNumInits() == 1) {
4383 if (DestType->isRecordType()) {
4384 QualType InitType = InitList->getInit(0)->getType();
4385 if (S.Context.hasSameUnqualifiedType(InitType, DestType) ||
4386 S.IsDerivedFrom(InitList->getBeginLoc(), InitType, DestType)) {
4387 Expr *InitListAsExpr = InitList;
4388 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
4389 DestType, Sequence,
4390 /*InitListSyntax*/false,
4391 /*IsInitListCopy*/true);
4392 return;
4393 }
4394 }
4395 if (const ArrayType *DestAT = S.Context.getAsArrayType(DestType)) {
4396 Expr *SubInit[1] = {InitList->getInit(0)};
4397 if (!isa<VariableArrayType>(DestAT) &&
4398 IsStringInit(SubInit[0], DestAT, S.Context) == SIF_None) {
4399 InitializationKind SubKind =
4400 Kind.getKind() == InitializationKind::IK_DirectList
4401 ? InitializationKind::CreateDirect(Kind.getLocation(),
4402 InitList->getLBraceLoc(),
4403 InitList->getRBraceLoc())
4404 : Kind;
4405 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
4406 /*TopLevelOfInitList*/ true,
4407 TreatUnavailableAsInvalid);
4408
4409 // TryStringLiteralInitialization() (in InitializeFrom()) will fail if
4410 // the element is not an appropriately-typed string literal, in which
4411 // case we should proceed as in C++11 (below).
4412 if (Sequence) {
4413 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4414 return;
4415 }
4416 }
4417 }
4418 }
4419
4420 // C++11 [dcl.init.list]p3:
4421 // - If T is an aggregate, aggregate initialization is performed.
4422 if ((DestType->isRecordType() && !DestType->isAggregateType()) ||
4423 (S.getLangOpts().CPlusPlus11 &&
4424 S.isStdInitializerList(DestType, nullptr))) {
4425 if (S.getLangOpts().CPlusPlus11) {
4426 // - Otherwise, if the initializer list has no elements and T is a
4427 // class type with a default constructor, the object is
4428 // value-initialized.
4429 if (InitList->getNumInits() == 0) {
4430 CXXRecordDecl *RD = DestType->getAsCXXRecordDecl();
4431 if (S.LookupDefaultConstructor(RD)) {
4432 TryValueInitialization(S, Entity, Kind, Sequence, InitList);
4433 return;
4434 }
4435 }
4436
4437 // - Otherwise, if T is a specialization of std::initializer_list<E>,
4438 // an initializer_list object constructed [...]
4439 if (TryInitializerListConstruction(S, InitList, DestType, Sequence,
4440 TreatUnavailableAsInvalid))
4441 return;
4442
4443 // - Otherwise, if T is a class type, constructors are considered.
4444 Expr *InitListAsExpr = InitList;
4445 TryConstructorInitialization(S, Entity, Kind, InitListAsExpr, DestType,
4446 DestType, Sequence, /*InitListSyntax*/true);
4447 } else
4448 Sequence.SetFailed(InitializationSequence::FK_InitListBadDestinationType);
4449 return;
4450 }
4451
4452 if (S.getLangOpts().CPlusPlus && !DestType->isAggregateType() &&
4453 InitList->getNumInits() == 1) {
4454 Expr *E = InitList->getInit(0);
4455
4456 // - Otherwise, if T is an enumeration with a fixed underlying type,
4457 // the initializer-list has a single element v, and the initialization
4458 // is direct-list-initialization, the object is initialized with the
4459 // value T(v); if a narrowing conversion is required to convert v to
4460 // the underlying type of T, the program is ill-formed.
4461 auto *ET = DestType->getAs<EnumType>();
4462 if (S.getLangOpts().CPlusPlus17 &&
4463 Kind.getKind() == InitializationKind::IK_DirectList &&
4464 ET && ET->getDecl()->isFixed() &&
4465 !S.Context.hasSameUnqualifiedType(E->getType(), DestType) &&
4466 (E->getType()->isIntegralOrEnumerationType() ||
4467 E->getType()->isFloatingType())) {
4468 // There are two ways that T(v) can work when T is an enumeration type.
4469 // If there is either an implicit conversion sequence from v to T or
4470 // a conversion function that can convert from v to T, then we use that.
4471 // Otherwise, if v is of integral, enumeration, or floating-point type,
4472 // it is converted to the enumeration type via its underlying type.
4473 // There is no overlap possible between these two cases (except when the
4474 // source value is already of the destination type), and the first
4475 // case is handled by the general case for single-element lists below.
4476 ImplicitConversionSequence ICS;
4477 ICS.setStandard();
4478 ICS.Standard.setAsIdentityConversion();
4479 if (!E->isRValue())
4480 ICS.Standard.First = ICK_Lvalue_To_Rvalue;
4481 // If E is of a floating-point type, then the conversion is ill-formed
4482 // due to narrowing, but go through the motions in order to produce the
4483 // right diagnostic.
4484 ICS.Standard.Second = E->getType()->isFloatingType()
4485 ? ICK_Floating_Integral
4486 : ICK_Integral_Conversion;
4487 ICS.Standard.setFromType(E->getType());
4488 ICS.Standard.setToType(0, E->getType());
4489 ICS.Standard.setToType(1, DestType);
4490 ICS.Standard.setToType(2, DestType);
4491 Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2),
4492 /*TopLevelOfInitList*/true);
4493 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4494 return;
4495 }
4496
4497 // - Otherwise, if the initializer list has a single element of type E
4498 // [...references are handled above...], the object or reference is
4499 // initialized from that element (by copy-initialization for
4500 // copy-list-initialization, or by direct-initialization for
4501 // direct-list-initialization); if a narrowing conversion is required
4502 // to convert the element to T, the program is ill-formed.
4503 //
4504 // Per core-24034, this is direct-initialization if we were performing
4505 // direct-list-initialization and copy-initialization otherwise.
4506 // We can't use InitListChecker for this, because it always performs
4507 // copy-initialization. This only matters if we might use an 'explicit'
4508 // conversion operator, or for the special case conversion of nullptr_t to
4509 // bool, so we only need to handle those cases.
4510 //
4511 // FIXME: Why not do this in all cases?
4512 Expr *Init = InitList->getInit(0);
4513 if (Init->getType()->isRecordType() ||
4514 (Init->getType()->isNullPtrType() && DestType->isBooleanType())) {
4515 InitializationKind SubKind =
4516 Kind.getKind() == InitializationKind::IK_DirectList
4517 ? InitializationKind::CreateDirect(Kind.getLocation(),
4518 InitList->getLBraceLoc(),
4519 InitList->getRBraceLoc())
4520 : Kind;
4521 Expr *SubInit[1] = { Init };
4522 Sequence.InitializeFrom(S, Entity, SubKind, SubInit,
4523 /*TopLevelOfInitList*/true,
4524 TreatUnavailableAsInvalid);
4525 if (Sequence)
4526 Sequence.RewrapReferenceInitList(Entity.getType(), InitList);
4527 return;
4528 }
4529 }
4530
4531 InitListChecker CheckInitList(S, Entity, InitList,
4532 DestType, /*VerifyOnly=*/true, TreatUnavailableAsInvalid);
4533 if (CheckInitList.HadError()) {
4534 Sequence.SetFailed(InitializationSequence::FK_ListInitializationFailed);
4535 return;
4536 }
4537
4538 // Add the list initialization step with the built init list.
4539 Sequence.AddListInitializationStep(DestType);
4540}
4541
4542/// Try a reference initialization that involves calling a conversion
4543/// function.
4544static OverloadingResult TryRefInitWithConversionFunction(
4545 Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind,
4546 Expr *Initializer, bool AllowRValues, bool IsLValueRef,
4547 InitializationSequence &Sequence) {
4548 QualType DestType = Entity.getType();
4549 QualType cv1T1 = DestType->castAs<ReferenceType>()->getPointeeType();
4550 QualType T1 = cv1T1.getUnqualifiedType();
4551 QualType cv2T2 = Initializer->getType();
4552 QualType T2 = cv2T2.getUnqualifiedType();
4553
4554 assert(!S.CompareReferenceRelationship(Initializer->getBeginLoc(), T1, T2) &&((!S.CompareReferenceRelationship(Initializer->getBeginLoc
(), T1, T2) && "Must have incompatible references when binding via conversion"
) ? static_cast<void> (0) : __assert_fail ("!S.CompareReferenceRelationship(Initializer->getBeginLoc(), T1, T2) && \"Must have incompatible references when binding via conversion\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4555, __PRETTY_FUNCTION__))
4555 "Must have incompatible references when binding via conversion")((!S.CompareReferenceRelationship(Initializer->getBeginLoc
(), T1, T2) && "Must have incompatible references when binding via conversion"
) ? static_cast<void> (0) : __assert_fail ("!S.CompareReferenceRelationship(Initializer->getBeginLoc(), T1, T2) && \"Must have incompatible references when binding via conversion\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4555, __PRETTY_FUNCTION__))
;
4556
4557 // Build the candidate set directly in the initialization sequence
4558 // structure, so that it will persist if we fail.
4559 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
4560 CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
4561
4562 // Determine whether we are allowed to call explicit conversion operators.
4563 // Note that none of [over.match.copy], [over.match.conv], nor
4564 // [over.match.ref] permit an explicit constructor to be chosen when
4565 // initializing a reference, not even for direct-initialization.
4566 bool AllowExplicitCtors = false;
4567 bool AllowExplicitConvs = Kind.allowExplicitConversionFunctionsInRefBinding();
4568
4569 const RecordType *T1RecordType = nullptr;
4570 if (AllowRValues && (T1RecordType = T1->getAs<RecordType>()) &&
4571 S.isCompleteType(Kind.getLocation(), T1)) {
4572 // The type we're converting to is a class type. Enumerate its constructors
4573 // to see if there is a suitable conversion.
4574 CXXRecordDecl *T1RecordDecl = cast<CXXRecordDecl>(T1RecordType->getDecl());
4575
4576 for (NamedDecl *D : S.LookupConstructors(T1RecordDecl)) {
4577 auto Info = getConstructorInfo(D);
4578 if (!Info.Constructor)
4579 continue;
4580
4581 if (!Info.Constructor->isInvalidDecl() &&
4582 Info.Constructor->isConvertingConstructor(/*AllowExplicit*/true)) {
4583 if (Info.ConstructorTmpl)
4584 S.AddTemplateOverloadCandidate(
4585 Info.ConstructorTmpl, Info.FoundDecl,
4586 /*ExplicitArgs*/ nullptr, Initializer, CandidateSet,
4587 /*SuppressUserConversions=*/true,
4588 /*PartialOverloading*/ false, AllowExplicitCtors);
4589 else
4590 S.AddOverloadCandidate(
4591 Info.Constructor, Info.FoundDecl, Initializer, CandidateSet,
4592 /*SuppressUserConversions=*/true,
4593 /*PartialOverloading*/ false, AllowExplicitCtors);
4594 }
4595 }
4596 }
4597 if (T1RecordType && T1RecordType->getDecl()->isInvalidDecl())
4598 return OR_No_Viable_Function;
4599
4600 const RecordType *T2RecordType = nullptr;
4601 if ((T2RecordType = T2->getAs<RecordType>()) &&
4602 S.isCompleteType(Kind.getLocation(), T2)) {
4603 // The type we're converting from is a class type, enumerate its conversion
4604 // functions.
4605 CXXRecordDecl *T2RecordDecl = cast<CXXRecordDecl>(T2RecordType->getDecl());
4606
4607 const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
4608 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4609 NamedDecl *D = *I;
4610 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4611 if (isa<UsingShadowDecl>(D))
4612 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4613
4614 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
4615 CXXConversionDecl *Conv;
4616 if (ConvTemplate)
4617 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4618 else
4619 Conv = cast<CXXConversionDecl>(D);
4620
4621 // If the conversion function doesn't return a reference type,
4622 // it can't be considered for this conversion unless we're allowed to
4623 // consider rvalues.
4624 // FIXME: Do we need to make sure that we only consider conversion
4625 // candidates with reference-compatible results? That might be needed to
4626 // break recursion.
4627 if ((AllowRValues ||
4628 Conv->getConversionType()->isLValueReferenceType())) {
4629 if (ConvTemplate)
4630 S.AddTemplateConversionCandidate(
4631 ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
4632 CandidateSet,
4633 /*AllowObjCConversionOnExplicit=*/false, AllowExplicitConvs);
4634 else
4635 S.AddConversionCandidate(
4636 Conv, I.getPair(), ActingDC, Initializer, DestType, CandidateSet,
4637 /*AllowObjCConversionOnExplicit=*/false, AllowExplicitConvs);
4638 }
4639 }
4640 }
4641 if (T2RecordType && T2RecordType->getDecl()->isInvalidDecl())
4642 return OR_No_Viable_Function;
4643
4644 SourceLocation DeclLoc = Initializer->getBeginLoc();
4645
4646 // Perform overload resolution. If it fails, return the failed result.
4647 OverloadCandidateSet::iterator Best;
4648 if (OverloadingResult Result
4649 = CandidateSet.BestViableFunction(S, DeclLoc, Best))
4650 return Result;
4651
4652 FunctionDecl *Function = Best->Function;
4653 // This is the overload that will be used for this initialization step if we
4654 // use this initialization. Mark it as referenced.
4655 Function->setReferenced();
4656
4657 // Compute the returned type and value kind of the conversion.
4658 QualType cv3T3;
4659 if (isa<CXXConversionDecl>(Function))
4660 cv3T3 = Function->getReturnType();
4661 else
4662 cv3T3 = T1;
4663
4664 ExprValueKind VK = VK_RValue;
4665 if (cv3T3->isLValueReferenceType())
4666 VK = VK_LValue;
4667 else if (const auto *RRef = cv3T3->getAs<RValueReferenceType>())
4668 VK = RRef->getPointeeType()->isFunctionType() ? VK_LValue : VK_XValue;
4669 cv3T3 = cv3T3.getNonLValueExprType(S.Context);
4670
4671 // Add the user-defined conversion step.
4672 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4673 Sequence.AddUserConversionStep(Function, Best->FoundDecl, cv3T3,
4674 HadMultipleCandidates);
4675
4676 // Determine whether we'll need to perform derived-to-base adjustments or
4677 // other conversions.
4678 Sema::ReferenceConversions RefConv;
4679 Sema::ReferenceCompareResult NewRefRelationship =
4680 S.CompareReferenceRelationship(DeclLoc, T1, cv3T3, &RefConv);
4681
4682 // Add the final conversion sequence, if necessary.
4683 if (NewRefRelationship == Sema::Ref_Incompatible) {
4684 assert(!isa<CXXConstructorDecl>(Function) &&((!isa<CXXConstructorDecl>(Function) && "should not have conversion after constructor"
) ? static_cast<void> (0) : __assert_fail ("!isa<CXXConstructorDecl>(Function) && \"should not have conversion after constructor\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4685, __PRETTY_FUNCTION__))
4685 "should not have conversion after constructor")((!isa<CXXConstructorDecl>(Function) && "should not have conversion after constructor"
) ? static_cast<void> (0) : __assert_fail ("!isa<CXXConstructorDecl>(Function) && \"should not have conversion after constructor\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4685, __PRETTY_FUNCTION__))
;
4686
4687 ImplicitConversionSequence ICS;
4688 ICS.setStandard();
4689 ICS.Standard = Best->FinalConversion;
4690 Sequence.AddConversionSequenceStep(ICS, ICS.Standard.getToType(2));
4691
4692 // Every implicit conversion results in a prvalue, except for a glvalue
4693 // derived-to-base conversion, which we handle below.
4694 cv3T3 = ICS.Standard.getToType(2);
4695 VK = VK_RValue;
4696 }
4697
4698 // If the converted initializer is a prvalue, its type T4 is adjusted to
4699 // type "cv1 T4" and the temporary materialization conversion is applied.
4700 //
4701 // We adjust the cv-qualifications to match the reference regardless of
4702 // whether we have a prvalue so that the AST records the change. In this
4703 // case, T4 is "cv3 T3".
4704 QualType cv1T4 = S.Context.getQualifiedType(cv3T3, cv1T1.getQualifiers());
4705 if (cv1T4.getQualifiers() != cv3T3.getQualifiers())
4706 Sequence.AddQualificationConversionStep(cv1T4, VK);
4707 Sequence.AddReferenceBindingStep(cv1T4, VK == VK_RValue);
4708 VK = IsLValueRef ? VK_LValue : VK_XValue;
4709
4710 if (RefConv & Sema::ReferenceConversions::DerivedToBase)
4711 Sequence.AddDerivedToBaseCastStep(cv1T1, VK);
4712 else if (RefConv & Sema::ReferenceConversions::ObjC)
4713 Sequence.AddObjCObjectConversionStep(cv1T1);
4714 else if (RefConv & Sema::ReferenceConversions::Function)
4715 Sequence.AddFunctionReferenceConversionStep(cv1T1);
4716 else if (RefConv & Sema::ReferenceConversions::Qualification) {
4717 if (!S.Context.hasSameType(cv1T4, cv1T1))
4718 Sequence.AddQualificationConversionStep(cv1T1, VK);
4719 }
4720
4721 return OR_Success;
4722}
4723
4724static void CheckCXX98CompatAccessibleCopy(Sema &S,
4725 const InitializedEntity &Entity,
4726 Expr *CurInitExpr);
4727
4728/// Attempt reference initialization (C++0x [dcl.init.ref])
4729static void TryReferenceInitialization(Sema &S,
4730 const InitializedEntity &Entity,
4731 const InitializationKind &Kind,
4732 Expr *Initializer,
4733 InitializationSequence &Sequence) {
4734 QualType DestType = Entity.getType();
4735 QualType cv1T1 = DestType->castAs<ReferenceType>()->getPointeeType();
4736 Qualifiers T1Quals;
4737 QualType T1 = S.Context.getUnqualifiedArrayType(cv1T1, T1Quals);
4738 QualType cv2T2 = S.getCompletedType(Initializer);
4739 Qualifiers T2Quals;
4740 QualType T2 = S.Context.getUnqualifiedArrayType(cv2T2, T2Quals);
4741
4742 // If the initializer is the address of an overloaded function, try
4743 // to resolve the overloaded function. If all goes well, T2 is the
4744 // type of the resulting function.
4745 if (ResolveOverloadedFunctionForReferenceBinding(S, Initializer, cv2T2, T2,
4746 T1, Sequence))
4747 return;
4748
4749 // Delegate everything else to a subfunction.
4750 TryReferenceInitializationCore(S, Entity, Kind, Initializer, cv1T1, T1,
4751 T1Quals, cv2T2, T2, T2Quals, Sequence);
4752}
4753
4754/// Determine whether an expression is a non-referenceable glvalue (one to
4755/// which a reference can never bind). Attempting to bind a reference to
4756/// such a glvalue will always create a temporary.
4757static bool isNonReferenceableGLValue(Expr *E) {
4758 return E->refersToBitField() || E->refersToVectorElement() ||
4759 E->refersToMatrixElement();
4760}
4761
4762/// Reference initialization without resolving overloaded functions.
4763///
4764/// We also can get here in C if we call a builtin which is declared as
4765/// a function with a parameter of reference type (such as __builtin_va_end()).
4766static void TryReferenceInitializationCore(Sema &S,
4767 const InitializedEntity &Entity,
4768 const InitializationKind &Kind,
4769 Expr *Initializer,
4770 QualType cv1T1, QualType T1,
4771 Qualifiers T1Quals,
4772 QualType cv2T2, QualType T2,
4773 Qualifiers T2Quals,
4774 InitializationSequence &Sequence) {
4775 QualType DestType = Entity.getType();
4776 SourceLocation DeclLoc = Initializer->getBeginLoc();
4777
4778 // Compute some basic properties of the types and the initializer.
4779 bool isLValueRef = DestType->isLValueReferenceType();
4780 bool isRValueRef = !isLValueRef;
4781 Expr::Classification InitCategory = Initializer->Classify(S.Context);
4782
4783 Sema::ReferenceConversions RefConv;
4784 Sema::ReferenceCompareResult RefRelationship =
4785 S.CompareReferenceRelationship(DeclLoc, cv1T1, cv2T2, &RefConv);
4786
4787 // C++0x [dcl.init.ref]p5:
4788 // A reference to type "cv1 T1" is initialized by an expression of type
4789 // "cv2 T2" as follows:
4790 //
4791 // - If the reference is an lvalue reference and the initializer
4792 // expression
4793 // Note the analogous bullet points for rvalue refs to functions. Because
4794 // there are no function rvalues in C++, rvalue refs to functions are treated
4795 // like lvalue refs.
4796 OverloadingResult ConvOvlResult = OR_Success;
4797 bool T1Function = T1->isFunctionType();
4798 if (isLValueRef || T1Function) {
4799 if (InitCategory.isLValue() && !isNonReferenceableGLValue(Initializer) &&
4800 (RefRelationship == Sema::Ref_Compatible ||
4801 (Kind.isCStyleOrFunctionalCast() &&
4802 RefRelationship == Sema::Ref_Related))) {
4803 // - is an lvalue (but is not a bit-field), and "cv1 T1" is
4804 // reference-compatible with "cv2 T2," or
4805 if (RefConv & (Sema::ReferenceConversions::DerivedToBase |
4806 Sema::ReferenceConversions::ObjC)) {
4807 // If we're converting the pointee, add any qualifiers first;
4808 // these qualifiers must all be top-level, so just convert to "cv1 T2".
4809 if (RefConv & (Sema::ReferenceConversions::Qualification))
4810 Sequence.AddQualificationConversionStep(
4811 S.Context.getQualifiedType(T2, T1Quals),
4812 Initializer->getValueKind());
4813 if (RefConv & Sema::ReferenceConversions::DerivedToBase)
4814 Sequence.AddDerivedToBaseCastStep(cv1T1, VK_LValue);
4815 else
4816 Sequence.AddObjCObjectConversionStep(cv1T1);
4817 } else if (RefConv & Sema::ReferenceConversions::Qualification) {
4818 // Perform a (possibly multi-level) qualification conversion.
4819 Sequence.AddQualificationConversionStep(cv1T1,
4820 Initializer->getValueKind());
4821 } else if (RefConv & Sema::ReferenceConversions::Function) {
4822 Sequence.AddFunctionReferenceConversionStep(cv1T1);
4823 }
4824
4825 // We only create a temporary here when binding a reference to a
4826 // bit-field or vector element. Those cases are't supposed to be
4827 // handled by this bullet, but the outcome is the same either way.
4828 Sequence.AddReferenceBindingStep(cv1T1, false);
4829 return;
4830 }
4831
4832 // - has a class type (i.e., T2 is a class type), where T1 is not
4833 // reference-related to T2, and can be implicitly converted to an
4834 // lvalue of type "cv3 T3," where "cv1 T1" is reference-compatible
4835 // with "cv3 T3" (this conversion is selected by enumerating the
4836 // applicable conversion functions (13.3.1.6) and choosing the best
4837 // one through overload resolution (13.3)),
4838 // If we have an rvalue ref to function type here, the rhs must be
4839 // an rvalue. DR1287 removed the "implicitly" here.
4840 if (RefRelationship == Sema::Ref_Incompatible && T2->isRecordType() &&
4841 (isLValueRef || InitCategory.isRValue())) {
4842 if (S.getLangOpts().CPlusPlus) {
4843 // Try conversion functions only for C++.
4844 ConvOvlResult = TryRefInitWithConversionFunction(
4845 S, Entity, Kind, Initializer, /*AllowRValues*/ isRValueRef,
4846 /*IsLValueRef*/ isLValueRef, Sequence);
4847 if (ConvOvlResult == OR_Success)
4848 return;
4849 if (ConvOvlResult != OR_No_Viable_Function)
4850 Sequence.SetOverloadFailure(
4851 InitializationSequence::FK_ReferenceInitOverloadFailed,
4852 ConvOvlResult);
4853 } else {
4854 ConvOvlResult = OR_No_Viable_Function;
4855 }
4856 }
4857 }
4858
4859 // - Otherwise, the reference shall be an lvalue reference to a
4860 // non-volatile const type (i.e., cv1 shall be const), or the reference
4861 // shall be an rvalue reference.
4862 // For address spaces, we interpret this to mean that an addr space
4863 // of a reference "cv1 T1" is a superset of addr space of "cv2 T2".
4864 if (isLValueRef && !(T1Quals.hasConst() && !T1Quals.hasVolatile() &&
4865 T1Quals.isAddressSpaceSupersetOf(T2Quals))) {
4866 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
4867 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
4868 else if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
4869 Sequence.SetOverloadFailure(
4870 InitializationSequence::FK_ReferenceInitOverloadFailed,
4871 ConvOvlResult);
4872 else if (!InitCategory.isLValue())
4873 Sequence.SetFailed(
4874 T1Quals.isAddressSpaceSupersetOf(T2Quals)
4875 ? InitializationSequence::
4876 FK_NonConstLValueReferenceBindingToTemporary
4877 : InitializationSequence::FK_ReferenceInitDropsQualifiers);
4878 else {
4879 InitializationSequence::FailureKind FK;
4880 switch (RefRelationship) {
4881 case Sema::Ref_Compatible:
4882 if (Initializer->refersToBitField())
4883 FK = InitializationSequence::
4884 FK_NonConstLValueReferenceBindingToBitfield;
4885 else if (Initializer->refersToVectorElement())
4886 FK = InitializationSequence::
4887 FK_NonConstLValueReferenceBindingToVectorElement;
4888 else if (Initializer->refersToMatrixElement())
4889 FK = InitializationSequence::
4890 FK_NonConstLValueReferenceBindingToMatrixElement;
4891 else
4892 llvm_unreachable("unexpected kind of compatible initializer")::llvm::llvm_unreachable_internal("unexpected kind of compatible initializer"
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 4892)
;
4893 break;
4894 case Sema::Ref_Related:
4895 FK = InitializationSequence::FK_ReferenceInitDropsQualifiers;
4896 break;
4897 case Sema::Ref_Incompatible:
4898 FK = InitializationSequence::
4899 FK_NonConstLValueReferenceBindingToUnrelated;
4900 break;
4901 }
4902 Sequence.SetFailed(FK);
4903 }
4904 return;
4905 }
4906
4907 // - If the initializer expression
4908 // - is an
4909 // [<=14] xvalue (but not a bit-field), class prvalue, array prvalue, or
4910 // [1z] rvalue (but not a bit-field) or
4911 // function lvalue and "cv1 T1" is reference-compatible with "cv2 T2"
4912 //
4913 // Note: functions are handled above and below rather than here...
4914 if (!T1Function &&
4915 (RefRelationship == Sema::Ref_Compatible ||
4916 (Kind.isCStyleOrFunctionalCast() &&
4917 RefRelationship == Sema::Ref_Related)) &&
4918 ((InitCategory.isXValue() && !isNonReferenceableGLValue(Initializer)) ||
4919 (InitCategory.isPRValue() &&
4920 (S.getLangOpts().CPlusPlus17 || T2->isRecordType() ||
4921 T2->isArrayType())))) {
4922 ExprValueKind ValueKind = InitCategory.isXValue() ? VK_XValue : VK_RValue;
4923 if (InitCategory.isPRValue() && T2->isRecordType()) {
4924 // The corresponding bullet in C++03 [dcl.init.ref]p5 gives the
4925 // compiler the freedom to perform a copy here or bind to the
4926 // object, while C++0x requires that we bind directly to the
4927 // object. Hence, we always bind to the object without making an
4928 // extra copy. However, in C++03 requires that we check for the
4929 // presence of a suitable copy constructor:
4930 //
4931 // The constructor that would be used to make the copy shall
4932 // be callable whether or not the copy is actually done.
4933 if (!S.getLangOpts().CPlusPlus11 && !S.getLangOpts().MicrosoftExt)
4934 Sequence.AddExtraneousCopyToTemporary(cv2T2);
4935 else if (S.getLangOpts().CPlusPlus11)
4936 CheckCXX98CompatAccessibleCopy(S, Entity, Initializer);
4937 }
4938
4939 // C++1z [dcl.init.ref]/5.2.1.2:
4940 // If the converted initializer is a prvalue, its type T4 is adjusted
4941 // to type "cv1 T4" and the temporary materialization conversion is
4942 // applied.
4943 // Postpone address space conversions to after the temporary materialization
4944 // conversion to allow creating temporaries in the alloca address space.
4945 auto T1QualsIgnoreAS = T1Quals;
4946 auto T2QualsIgnoreAS = T2Quals;
4947 if (T1Quals.getAddressSpace() != T2Quals.getAddressSpace()) {
4948 T1QualsIgnoreAS.removeAddressSpace();
4949 T2QualsIgnoreAS.removeAddressSpace();
4950 }
4951 QualType cv1T4 = S.Context.getQualifiedType(cv2T2, T1QualsIgnoreAS);
4952 if (T1QualsIgnoreAS != T2QualsIgnoreAS)
4953 Sequence.AddQualificationConversionStep(cv1T4, ValueKind);
4954 Sequence.AddReferenceBindingStep(cv1T4, ValueKind == VK_RValue);
4955 ValueKind = isLValueRef ? VK_LValue : VK_XValue;
4956 // Add addr space conversion if required.
4957 if (T1Quals.getAddressSpace() != T2Quals.getAddressSpace()) {
4958 auto T4Quals = cv1T4.getQualifiers();
4959 T4Quals.addAddressSpace(T1Quals.getAddressSpace());
4960 QualType cv1T4WithAS = S.Context.getQualifiedType(T2, T4Quals);
4961 Sequence.AddQualificationConversionStep(cv1T4WithAS, ValueKind);
4962 cv1T4 = cv1T4WithAS;
4963 }
4964
4965 // In any case, the reference is bound to the resulting glvalue (or to
4966 // an appropriate base class subobject).
4967 if (RefConv & Sema::ReferenceConversions::DerivedToBase)
4968 Sequence.AddDerivedToBaseCastStep(cv1T1, ValueKind);
4969 else if (RefConv & Sema::ReferenceConversions::ObjC)
4970 Sequence.AddObjCObjectConversionStep(cv1T1);
4971 else if (RefConv & Sema::ReferenceConversions::Qualification) {
4972 if (!S.Context.hasSameType(cv1T4, cv1T1))
4973 Sequence.AddQualificationConversionStep(cv1T1, ValueKind);
4974 }
4975 return;
4976 }
4977
4978 // - has a class type (i.e., T2 is a class type), where T1 is not
4979 // reference-related to T2, and can be implicitly converted to an
4980 // xvalue, class prvalue, or function lvalue of type "cv3 T3",
4981 // where "cv1 T1" is reference-compatible with "cv3 T3",
4982 //
4983 // DR1287 removes the "implicitly" here.
4984 if (T2->isRecordType()) {
4985 if (RefRelationship == Sema::Ref_Incompatible) {
4986 ConvOvlResult = TryRefInitWithConversionFunction(
4987 S, Entity, Kind, Initializer, /*AllowRValues*/ true,
4988 /*IsLValueRef*/ isLValueRef, Sequence);
4989 if (ConvOvlResult)
4990 Sequence.SetOverloadFailure(
4991 InitializationSequence::FK_ReferenceInitOverloadFailed,
4992 ConvOvlResult);
4993
4994 return;
4995 }
4996
4997 if (RefRelationship == Sema::Ref_Compatible &&
4998 isRValueRef && InitCategory.isLValue()) {
4999 Sequence.SetFailed(
5000 InitializationSequence::FK_RValueReferenceBindingToLValue);
5001 return;
5002 }
5003
5004 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
5005 return;
5006 }
5007
5008 // - Otherwise, a temporary of type "cv1 T1" is created and initialized
5009 // from the initializer expression using the rules for a non-reference
5010 // copy-initialization (8.5). The reference is then bound to the
5011 // temporary. [...]
5012
5013 // Ignore address space of reference type at this point and perform address
5014 // space conversion after the reference binding step.
5015 QualType cv1T1IgnoreAS =
5016 T1Quals.hasAddressSpace()
5017 ? S.Context.getQualifiedType(T1, T1Quals.withoutAddressSpace())
5018 : cv1T1;
5019
5020 InitializedEntity TempEntity =
5021 InitializedEntity::InitializeTemporary(cv1T1IgnoreAS);
5022
5023 // FIXME: Why do we use an implicit conversion here rather than trying
5024 // copy-initialization?
5025 ImplicitConversionSequence ICS
5026 = S.TryImplicitConversion(Initializer, TempEntity.getType(),
5027 /*SuppressUserConversions=*/false,
5028 Sema::AllowedExplicit::None,
5029 /*FIXME:InOverloadResolution=*/false,
5030 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
5031 /*AllowObjCWritebackConversion=*/false);
5032
5033 if (ICS.isBad()) {
5034 // FIXME: Use the conversion function set stored in ICS to turn
5035 // this into an overloading ambiguity diagnostic. However, we need
5036 // to keep that set as an OverloadCandidateSet rather than as some
5037 // other kind of set.
5038 if (ConvOvlResult && !Sequence.getFailedCandidateSet().empty())
5039 Sequence.SetOverloadFailure(
5040 InitializationSequence::FK_ReferenceInitOverloadFailed,
5041 ConvOvlResult);
5042 else if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy)
5043 Sequence.SetFailed(InitializationSequence::FK_AddressOfOverloadFailed);
5044 else
5045 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitFailed);
5046 return;
5047 } else {
5048 Sequence.AddConversionSequenceStep(ICS, TempEntity.getType());
5049 }
5050
5051 // [...] If T1 is reference-related to T2, cv1 must be the
5052 // same cv-qualification as, or greater cv-qualification
5053 // than, cv2; otherwise, the program is ill-formed.
5054 unsigned T1CVRQuals = T1Quals.getCVRQualifiers();
5055 unsigned T2CVRQuals = T2Quals.getCVRQualifiers();
5056 if ((RefRelationship == Sema::Ref_Related &&
5057 (T1CVRQuals | T2CVRQuals) != T1CVRQuals) ||
5058 !T1Quals.isAddressSpaceSupersetOf(T2Quals)) {
5059 Sequence.SetFailed(InitializationSequence::FK_ReferenceInitDropsQualifiers);
5060 return;
5061 }
5062
5063 // [...] If T1 is reference-related to T2 and the reference is an rvalue
5064 // reference, the initializer expression shall not be an lvalue.
5065 if (RefRelationship >= Sema::Ref_Related && !isLValueRef &&
5066 InitCategory.isLValue()) {
5067 Sequence.SetFailed(
5068 InitializationSequence::FK_RValueReferenceBindingToLValue);
5069 return;
5070 }
5071
5072 Sequence.AddReferenceBindingStep(cv1T1IgnoreAS, /*BindingTemporary=*/true);
5073
5074 if (T1Quals.hasAddressSpace()) {
5075 if (!Qualifiers::isAddressSpaceSupersetOf(T1Quals.getAddressSpace(),
5076 LangAS::Default)) {
5077 Sequence.SetFailed(
5078 InitializationSequence::FK_ReferenceAddrspaceMismatchTemporary);
5079 return;
5080 }
5081 Sequence.AddQualificationConversionStep(cv1T1, isLValueRef ? VK_LValue
5082 : VK_XValue);
5083 }
5084}
5085
5086/// Attempt character array initialization from a string literal
5087/// (C++ [dcl.init.string], C99 6.7.8).
5088static void TryStringLiteralInitialization(Sema &S,
5089 const InitializedEntity &Entity,
5090 const InitializationKind &Kind,
5091 Expr *Initializer,
5092 InitializationSequence &Sequence) {
5093 Sequence.AddStringInitStep(Entity.getType());
5094}
5095
5096/// Attempt value initialization (C++ [dcl.init]p7).
5097static void TryValueInitialization(Sema &S,
5098 const InitializedEntity &Entity,
5099 const InitializationKind &Kind,
5100 InitializationSequence &Sequence,
5101 InitListExpr *InitList) {
5102 assert((!InitList || InitList->getNumInits() == 0) &&(((!InitList || InitList->getNumInits() == 0) && "Shouldn't use value-init for non-empty init lists"
) ? static_cast<void> (0) : __assert_fail ("(!InitList || InitList->getNumInits() == 0) && \"Shouldn't use value-init for non-empty init lists\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5103, __PRETTY_FUNCTION__))
5103 "Shouldn't use value-init for non-empty init lists")(((!InitList || InitList->getNumInits() == 0) && "Shouldn't use value-init for non-empty init lists"
) ? static_cast<void> (0) : __assert_fail ("(!InitList || InitList->getNumInits() == 0) && \"Shouldn't use value-init for non-empty init lists\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5103, __PRETTY_FUNCTION__))
;
5104
5105 // C++98 [dcl.init]p5, C++11 [dcl.init]p7:
5106 //
5107 // To value-initialize an object of type T means:
5108 QualType T = Entity.getType();
5109
5110 // -- if T is an array type, then each element is value-initialized;
5111 T = S.Context.getBaseElementType(T);
5112
5113 if (const RecordType *RT = T->getAs<RecordType>()) {
5114 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
5115 bool NeedZeroInitialization = true;
5116 // C++98:
5117 // -- if T is a class type (clause 9) with a user-declared constructor
5118 // (12.1), then the default constructor for T is called (and the
5119 // initialization is ill-formed if T has no accessible default
5120 // constructor);
5121 // C++11:
5122 // -- if T is a class type (clause 9) with either no default constructor
5123 // (12.1 [class.ctor]) or a default constructor that is user-provided
5124 // or deleted, then the object is default-initialized;
5125 //
5126 // Note that the C++11 rule is the same as the C++98 rule if there are no
5127 // defaulted or deleted constructors, so we just use it unconditionally.
5128 CXXConstructorDecl *CD = S.LookupDefaultConstructor(ClassDecl);
5129 if (!CD || !CD->getCanonicalDecl()->isDefaulted() || CD->isDeleted())
5130 NeedZeroInitialization = false;
5131
5132 // -- if T is a (possibly cv-qualified) non-union class type without a
5133 // user-provided or deleted default constructor, then the object is
5134 // zero-initialized and, if T has a non-trivial default constructor,
5135 // default-initialized;
5136 // The 'non-union' here was removed by DR1502. The 'non-trivial default
5137 // constructor' part was removed by DR1507.
5138 if (NeedZeroInitialization)
5139 Sequence.AddZeroInitializationStep(Entity.getType());
5140
5141 // C++03:
5142 // -- if T is a non-union class type without a user-declared constructor,
5143 // then every non-static data member and base class component of T is
5144 // value-initialized;
5145 // [...] A program that calls for [...] value-initialization of an
5146 // entity of reference type is ill-formed.
5147 //
5148 // C++11 doesn't need this handling, because value-initialization does not
5149 // occur recursively there, and the implicit default constructor is
5150 // defined as deleted in the problematic cases.
5151 if (!S.getLangOpts().CPlusPlus11 &&
5152 ClassDecl->hasUninitializedReferenceMember()) {
5153 Sequence.SetFailed(InitializationSequence::FK_TooManyInitsForReference);
5154 return;
5155 }
5156
5157 // If this is list-value-initialization, pass the empty init list on when
5158 // building the constructor call. This affects the semantics of a few
5159 // things (such as whether an explicit default constructor can be called).
5160 Expr *InitListAsExpr = InitList;
5161 MultiExprArg Args(&InitListAsExpr, InitList ? 1 : 0);
5162 bool InitListSyntax = InitList;
5163
5164 // FIXME: Instead of creating a CXXConstructExpr of array type here,
5165 // wrap a class-typed CXXConstructExpr in an ArrayInitLoopExpr.
5166 return TryConstructorInitialization(
5167 S, Entity, Kind, Args, T, Entity.getType(), Sequence, InitListSyntax);
5168 }
5169 }
5170
5171 Sequence.AddZeroInitializationStep(Entity.getType());
5172}
5173
5174/// Attempt default initialization (C++ [dcl.init]p6).
5175static void TryDefaultInitialization(Sema &S,
5176 const InitializedEntity &Entity,
5177 const InitializationKind &Kind,
5178 InitializationSequence &Sequence) {
5179 assert(Kind.getKind() == InitializationKind::IK_Default)((Kind.getKind() == InitializationKind::IK_Default) ? static_cast
<void> (0) : __assert_fail ("Kind.getKind() == InitializationKind::IK_Default"
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5179, __PRETTY_FUNCTION__))
;
5180
5181 // C++ [dcl.init]p6:
5182 // To default-initialize an object of type T means:
5183 // - if T is an array type, each element is default-initialized;
5184 QualType DestType = S.Context.getBaseElementType(Entity.getType());
5185
5186 // - if T is a (possibly cv-qualified) class type (Clause 9), the default
5187 // constructor for T is called (and the initialization is ill-formed if
5188 // T has no accessible default constructor);
5189 if (DestType->isRecordType() && S.getLangOpts().CPlusPlus) {
5190 TryConstructorInitialization(S, Entity, Kind, None, DestType,
5191 Entity.getType(), Sequence);
5192 return;
5193 }
5194
5195 // - otherwise, no initialization is performed.
5196
5197 // If a program calls for the default initialization of an object of
5198 // a const-qualified type T, T shall be a class type with a user-provided
5199 // default constructor.
5200 if (DestType.isConstQualified() && S.getLangOpts().CPlusPlus) {
5201 if (!maybeRecoverWithZeroInitialization(S, Sequence, Entity))
5202 Sequence.SetFailed(InitializationSequence::FK_DefaultInitOfConst);
5203 return;
5204 }
5205
5206 // If the destination type has a lifetime property, zero-initialize it.
5207 if (DestType.getQualifiers().hasObjCLifetime()) {
5208 Sequence.AddZeroInitializationStep(Entity.getType());
5209 return;
5210 }
5211}
5212
5213/// Attempt a user-defined conversion between two types (C++ [dcl.init]),
5214/// which enumerates all conversion functions and performs overload resolution
5215/// to select the best.
5216static void TryUserDefinedConversion(Sema &S,
5217 QualType DestType,
5218 const InitializationKind &Kind,
5219 Expr *Initializer,
5220 InitializationSequence &Sequence,
5221 bool TopLevelOfInitList) {
5222 assert(!DestType->isReferenceType() && "References are handled elsewhere")((!DestType->isReferenceType() && "References are handled elsewhere"
) ? static_cast<void> (0) : __assert_fail ("!DestType->isReferenceType() && \"References are handled elsewhere\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5222, __PRETTY_FUNCTION__))
;
5223 QualType SourceType = Initializer->getType();
5224 assert((DestType->isRecordType() || SourceType->isRecordType()) &&(((DestType->isRecordType() || SourceType->isRecordType
()) && "Must have a class type to perform a user-defined conversion"
) ? static_cast<void> (0) : __assert_fail ("(DestType->isRecordType() || SourceType->isRecordType()) && \"Must have a class type to perform a user-defined conversion\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5225, __PRETTY_FUNCTION__))
5225 "Must have a class type to perform a user-defined conversion")(((DestType->isRecordType() || SourceType->isRecordType
()) && "Must have a class type to perform a user-defined conversion"
) ? static_cast<void> (0) : __assert_fail ("(DestType->isRecordType() || SourceType->isRecordType()) && \"Must have a class type to perform a user-defined conversion\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5225, __PRETTY_FUNCTION__))
;
5226
5227 // Build the candidate set directly in the initialization sequence
5228 // structure, so that it will persist if we fail.
5229 OverloadCandidateSet &CandidateSet = Sequence.getFailedCandidateSet();
5230 CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
5231 CandidateSet.setDestAS(DestType.getQualifiers().getAddressSpace());
5232
5233 // Determine whether we are allowed to call explicit constructors or
5234 // explicit conversion operators.
5235 bool AllowExplicit = Kind.AllowExplicit();
5236
5237 if (const RecordType *DestRecordType = DestType->getAs<RecordType>()) {
5238 // The type we're converting to is a class type. Enumerate its constructors
5239 // to see if there is a suitable conversion.
5240 CXXRecordDecl *DestRecordDecl
5241 = cast<CXXRecordDecl>(DestRecordType->getDecl());
5242
5243 // Try to complete the type we're converting to.
5244 if (S.isCompleteType(Kind.getLocation(), DestType)) {
5245 for (NamedDecl *D : S.LookupConstructors(DestRecordDecl)) {
5246 auto Info = getConstructorInfo(D);
5247 if (!Info.Constructor)
5248 continue;
5249
5250 if (!Info.Constructor->isInvalidDecl() &&
5251 Info.Constructor->isConvertingConstructor(/*AllowExplicit*/true)) {
5252 if (Info.ConstructorTmpl)
5253 S.AddTemplateOverloadCandidate(
5254 Info.ConstructorTmpl, Info.FoundDecl,
5255 /*ExplicitArgs*/ nullptr, Initializer, CandidateSet,
5256 /*SuppressUserConversions=*/true,
5257 /*PartialOverloading*/ false, AllowExplicit);
5258 else
5259 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
5260 Initializer, CandidateSet,
5261 /*SuppressUserConversions=*/true,
5262 /*PartialOverloading*/ false, AllowExplicit);
5263 }
5264 }
5265 }
5266 }
5267
5268 SourceLocation DeclLoc = Initializer->getBeginLoc();
5269
5270 if (const RecordType *SourceRecordType = SourceType->getAs<RecordType>()) {
5271 // The type we're converting from is a class type, enumerate its conversion
5272 // functions.
5273
5274 // We can only enumerate the conversion functions for a complete type; if
5275 // the type isn't complete, simply skip this step.
5276 if (S.isCompleteType(DeclLoc, SourceType)) {
5277 CXXRecordDecl *SourceRecordDecl
5278 = cast<CXXRecordDecl>(SourceRecordType->getDecl());
5279
5280 const auto &Conversions =
5281 SourceRecordDecl->getVisibleConversionFunctions();
5282 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
5283 NamedDecl *D = *I;
5284 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
5285 if (isa<UsingShadowDecl>(D))
5286 D = cast<UsingShadowDecl>(D)->getTargetDecl();
5287
5288 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
5289 CXXConversionDecl *Conv;
5290 if (ConvTemplate)
5291 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
5292 else
5293 Conv = cast<CXXConversionDecl>(D);
5294
5295 if (ConvTemplate)
5296 S.AddTemplateConversionCandidate(
5297 ConvTemplate, I.getPair(), ActingDC, Initializer, DestType,
5298 CandidateSet, AllowExplicit, AllowExplicit);
5299 else
5300 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Initializer,
5301 DestType, CandidateSet, AllowExplicit,
5302 AllowExplicit);
5303 }
5304 }
5305 }
5306
5307 // Perform overload resolution. If it fails, return the failed result.
5308 OverloadCandidateSet::iterator Best;
5309 if (OverloadingResult Result
5310 = CandidateSet.BestViableFunction(S, DeclLoc, Best)) {
5311 Sequence.SetOverloadFailure(
5312 InitializationSequence::FK_UserConversionOverloadFailed, Result);
5313
5314 // [class.copy.elision]p3:
5315 // In some copy-initialization contexts, a two-stage overload resolution
5316 // is performed.
5317 // If the first overload resolution selects a deleted function, we also
5318 // need the initialization sequence to decide whether to perform the second
5319 // overload resolution.
5320 if (!(Result == OR_Deleted &&
5321 Kind.getKind() == InitializationKind::IK_Copy))
5322 return;
5323 }
5324
5325 FunctionDecl *Function = Best->Function;
5326 Function->setReferenced();
5327 bool HadMultipleCandidates = (CandidateSet.size() > 1);
5328
5329 if (isa<CXXConstructorDecl>(Function)) {
5330 // Add the user-defined conversion step. Any cv-qualification conversion is
5331 // subsumed by the initialization. Per DR5, the created temporary is of the
5332 // cv-unqualified type of the destination.
5333 Sequence.AddUserConversionStep(Function, Best->FoundDecl,
5334 DestType.getUnqualifiedType(),
5335 HadMultipleCandidates);
5336
5337 // C++14 and before:
5338 // - if the function is a constructor, the call initializes a temporary
5339 // of the cv-unqualified version of the destination type. The [...]
5340 // temporary [...] is then used to direct-initialize, according to the
5341 // rules above, the object that is the destination of the
5342 // copy-initialization.
5343 // Note that this just performs a simple object copy from the temporary.
5344 //
5345 // C++17:
5346 // - if the function is a constructor, the call is a prvalue of the
5347 // cv-unqualified version of the destination type whose return object
5348 // is initialized by the constructor. The call is used to
5349 // direct-initialize, according to the rules above, the object that
5350 // is the destination of the copy-initialization.
5351 // Therefore we need to do nothing further.
5352 //
5353 // FIXME: Mark this copy as extraneous.
5354 if (!S.getLangOpts().CPlusPlus17)
5355 Sequence.AddFinalCopy(DestType);
5356 else if (DestType.hasQualifiers())
5357 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
5358 return;
5359 }
5360
5361 // Add the user-defined conversion step that calls the conversion function.
5362 QualType ConvType = Function->getCallResultType();
5363 Sequence.AddUserConversionStep(Function, Best->FoundDecl, ConvType,
5364 HadMultipleCandidates);
5365
5366 if (ConvType->getAs<RecordType>()) {
5367 // The call is used to direct-initialize [...] the object that is the
5368 // destination of the copy-initialization.
5369 //
5370 // In C++17, this does not call a constructor if we enter /17.6.1:
5371 // - If the initializer expression is a prvalue and the cv-unqualified
5372 // version of the source type is the same as the class of the
5373 // destination [... do not make an extra copy]
5374 //
5375 // FIXME: Mark this copy as extraneous.
5376 if (!S.getLangOpts().CPlusPlus17 ||
5377 Function->getReturnType()->isReferenceType() ||
5378 !S.Context.hasSameUnqualifiedType(ConvType, DestType))
5379 Sequence.AddFinalCopy(DestType);
5380 else if (!S.Context.hasSameType(ConvType, DestType))
5381 Sequence.AddQualificationConversionStep(DestType, VK_RValue);
5382 return;
5383 }
5384
5385 // If the conversion following the call to the conversion function
5386 // is interesting, add it as a separate step.
5387 if (Best->FinalConversion.First || Best->FinalConversion.Second ||
5388 Best->FinalConversion.Third) {
5389 ImplicitConversionSequence ICS;
5390 ICS.setStandard();
5391 ICS.Standard = Best->FinalConversion;
5392 Sequence.AddConversionSequenceStep(ICS, DestType, TopLevelOfInitList);
5393 }
5394}
5395
5396/// An egregious hack for compatibility with libstdc++-4.2: in <tr1/hashtable>,
5397/// a function with a pointer return type contains a 'return false;' statement.
5398/// In C++11, 'false' is not a null pointer, so this breaks the build of any
5399/// code using that header.
5400///
5401/// Work around this by treating 'return false;' as zero-initializing the result
5402/// if it's used in a pointer-returning function in a system header.
5403static bool isLibstdcxxPointerReturnFalseHack(Sema &S,
5404 const InitializedEntity &Entity,
5405 const Expr *Init) {
5406 return S.getLangOpts().CPlusPlus11 &&
5407 Entity.getKind() == InitializedEntity::EK_Result &&
5408 Entity.getType()->isPointerType() &&
5409 isa<CXXBoolLiteralExpr>(Init) &&
5410 !cast<CXXBoolLiteralExpr>(Init)->getValue() &&
5411 S.getSourceManager().isInSystemHeader(Init->getExprLoc());
5412}
5413
5414/// The non-zero enum values here are indexes into diagnostic alternatives.
5415enum InvalidICRKind { IIK_okay, IIK_nonlocal, IIK_nonscalar };
5416
5417/// Determines whether this expression is an acceptable ICR source.
5418static InvalidICRKind isInvalidICRSource(ASTContext &C, Expr *e,
5419 bool isAddressOf, bool &isWeakAccess) {
5420 // Skip parens.
5421 e = e->IgnoreParens();
5422
5423 // Skip address-of nodes.
5424 if (UnaryOperator *op = dyn_cast<UnaryOperator>(e)) {
5425 if (op->getOpcode() == UO_AddrOf)
5426 return isInvalidICRSource(C, op->getSubExpr(), /*addressof*/ true,
5427 isWeakAccess);
5428
5429 // Skip certain casts.
5430 } else if (CastExpr *ce = dyn_cast<CastExpr>(e)) {
5431 switch (ce->getCastKind()) {
5432 case CK_Dependent:
5433 case CK_BitCast:
5434 case CK_LValueBitCast:
5435 case CK_NoOp:
5436 return isInvalidICRSource(C, ce->getSubExpr(), isAddressOf, isWeakAccess);
5437
5438 case CK_ArrayToPointerDecay:
5439 return IIK_nonscalar;
5440
5441 case CK_NullToPointer:
5442 return IIK_okay;
5443
5444 default:
5445 break;
5446 }
5447
5448 // If we have a declaration reference, it had better be a local variable.
5449 } else if (isa<DeclRefExpr>(e)) {
5450 // set isWeakAccess to true, to mean that there will be an implicit
5451 // load which requires a cleanup.
5452 if (e->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
5453 isWeakAccess = true;
5454
5455 if (!isAddressOf) return IIK_nonlocal;
5456
5457 VarDecl *var = dyn_cast<VarDecl>(cast<DeclRefExpr>(e)->getDecl());
5458 if (!var) return IIK_nonlocal;
5459
5460 return (var->hasLocalStorage() ? IIK_okay : IIK_nonlocal);
5461
5462 // If we have a conditional operator, check both sides.
5463 } else if (ConditionalOperator *cond = dyn_cast<ConditionalOperator>(e)) {
5464 if (InvalidICRKind iik = isInvalidICRSource(C, cond->getLHS(), isAddressOf,
5465 isWeakAccess))
5466 return iik;
5467
5468 return isInvalidICRSource(C, cond->getRHS(), isAddressOf, isWeakAccess);
5469
5470 // These are never scalar.
5471 } else if (isa<ArraySubscriptExpr>(e)) {
5472 return IIK_nonscalar;
5473
5474 // Otherwise, it needs to be a null pointer constant.
5475 } else {
5476 return (e->isNullPointerConstant(C, Expr::NPC_ValueDependentIsNull)
5477 ? IIK_okay : IIK_nonlocal);
5478 }
5479
5480 return IIK_nonlocal;
5481}
5482
5483/// Check whether the given expression is a valid operand for an
5484/// indirect copy/restore.
5485static void checkIndirectCopyRestoreSource(Sema &S, Expr *src) {
5486 assert(src->isRValue())((src->isRValue()) ? static_cast<void> (0) : __assert_fail
("src->isRValue()", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5486, __PRETTY_FUNCTION__))
;
5487 bool isWeakAccess = false;
5488 InvalidICRKind iik = isInvalidICRSource(S.Context, src, false, isWeakAccess);
5489 // If isWeakAccess to true, there will be an implicit
5490 // load which requires a cleanup.
5491 if (S.getLangOpts().ObjCAutoRefCount && isWeakAccess)
5492 S.Cleanup.setExprNeedsCleanups(true);
5493
5494 if (iik == IIK_okay) return;
5495
5496 S.Diag(src->getExprLoc(), diag::err_arc_nonlocal_writeback)
5497 << ((unsigned) iik - 1) // shift index into diagnostic explanations
5498 << src->getSourceRange();
5499}
5500
5501/// Determine whether we have compatible array types for the
5502/// purposes of GNU by-copy array initialization.
5503static bool hasCompatibleArrayTypes(ASTContext &Context, const ArrayType *Dest,
5504 const ArrayType *Source) {
5505 // If the source and destination array types are equivalent, we're
5506 // done.
5507 if (Context.hasSameType(QualType(Dest, 0), QualType(Source, 0)))
5508 return true;
5509
5510 // Make sure that the element types are the same.
5511 if (!Context.hasSameType(Dest->getElementType(), Source->getElementType()))
5512 return false;
5513
5514 // The only mismatch we allow is when the destination is an
5515 // incomplete array type and the source is a constant array type.
5516 return Source->isConstantArrayType() && Dest->isIncompleteArrayType();
5517}
5518
5519static bool tryObjCWritebackConversion(Sema &S,
5520 InitializationSequence &Sequence,
5521 const InitializedEntity &Entity,
5522 Expr *Initializer) {
5523 bool ArrayDecay = false;
5524 QualType ArgType = Initializer->getType();
5525 QualType ArgPointee;
5526 if (const ArrayType *ArgArrayType = S.Context.getAsArrayType(ArgType)) {
5527 ArrayDecay = true;
5528 ArgPointee = ArgArrayType->getElementType();
5529 ArgType = S.Context.getPointerType(ArgPointee);
5530 }
5531
5532 // Handle write-back conversion.
5533 QualType ConvertedArgType;
5534 if (!S.isObjCWritebackConversion(ArgType, Entity.getType(),
5535 ConvertedArgType))
5536 return false;
5537
5538 // We should copy unless we're passing to an argument explicitly
5539 // marked 'out'.
5540 bool ShouldCopy = true;
5541 if (ParmVarDecl *param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
5542 ShouldCopy = (param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
5543
5544 // Do we need an lvalue conversion?
5545 if (ArrayDecay || Initializer->isGLValue()) {
5546 ImplicitConversionSequence ICS;
5547 ICS.setStandard();
5548 ICS.Standard.setAsIdentityConversion();
5549
5550 QualType ResultType;
5551 if (ArrayDecay) {
5552 ICS.Standard.First = ICK_Array_To_Pointer;
5553 ResultType = S.Context.getPointerType(ArgPointee);
5554 } else {
5555 ICS.Standard.First = ICK_Lvalue_To_Rvalue;
5556 ResultType = Initializer->getType().getNonLValueExprType(S.Context);
5557 }
5558
5559 Sequence.AddConversionSequenceStep(ICS, ResultType);
5560 }
5561
5562 Sequence.AddPassByIndirectCopyRestoreStep(Entity.getType(), ShouldCopy);
5563 return true;
5564}
5565
5566static bool TryOCLSamplerInitialization(Sema &S,
5567 InitializationSequence &Sequence,
5568 QualType DestType,
5569 Expr *Initializer) {
5570 if (!S.getLangOpts().OpenCL || !DestType->isSamplerT() ||
5571 (!Initializer->isIntegerConstantExpr(S.Context) &&
5572 !Initializer->getType()->isSamplerT()))
5573 return false;
5574
5575 Sequence.AddOCLSamplerInitStep(DestType);
5576 return true;
5577}
5578
5579static bool IsZeroInitializer(Expr *Initializer, Sema &S) {
5580 return Initializer->isIntegerConstantExpr(S.getASTContext()) &&
5581 (Initializer->EvaluateKnownConstInt(S.getASTContext()) == 0);
5582}
5583
5584static bool TryOCLZeroOpaqueTypeInitialization(Sema &S,
5585 InitializationSequence &Sequence,
5586 QualType DestType,
5587 Expr *Initializer) {
5588 if (!S.getLangOpts().OpenCL)
5589 return false;
5590
5591 //
5592 // OpenCL 1.2 spec, s6.12.10
5593 //
5594 // The event argument can also be used to associate the
5595 // async_work_group_copy with a previous async copy allowing
5596 // an event to be shared by multiple async copies; otherwise
5597 // event should be zero.
5598 //
5599 if (DestType->isEventT() || DestType->isQueueT()) {
5600 if (!IsZeroInitializer(Initializer, S))
5601 return false;
5602
5603 Sequence.AddOCLZeroOpaqueTypeStep(DestType);
5604 return true;
5605 }
5606
5607 // We should allow zero initialization for all types defined in the
5608 // cl_intel_device_side_avc_motion_estimation extension, except
5609 // intel_sub_group_avc_mce_payload_t and intel_sub_group_avc_mce_result_t.
5610 if (S.getOpenCLOptions().isEnabled(
5611 "cl_intel_device_side_avc_motion_estimation") &&
5612 DestType->isOCLIntelSubgroupAVCType()) {
5613 if (DestType->isOCLIntelSubgroupAVCMcePayloadType() ||
5614 DestType->isOCLIntelSubgroupAVCMceResultType())
5615 return false;
5616 if (!IsZeroInitializer(Initializer, S))
5617 return false;
5618
5619 Sequence.AddOCLZeroOpaqueTypeStep(DestType);
5620 return true;
5621 }
5622
5623 return false;
5624}
5625
5626InitializationSequence::InitializationSequence(
5627 Sema &S, const InitializedEntity &Entity, const InitializationKind &Kind,
5628 MultiExprArg Args, bool TopLevelOfInitList, bool TreatUnavailableAsInvalid)
5629 : FailedOverloadResult(OR_Success),
5630 FailedCandidateSet(Kind.getLocation(), OverloadCandidateSet::CSK_Normal) {
5631 InitializeFrom(S, Entity, Kind, Args, TopLevelOfInitList,
5632 TreatUnavailableAsInvalid);
5633}
5634
5635/// Tries to get a FunctionDecl out of `E`. If it succeeds and we can take the
5636/// address of that function, this returns true. Otherwise, it returns false.
5637static bool isExprAnUnaddressableFunction(Sema &S, const Expr *E) {
5638 auto *DRE = dyn_cast<DeclRefExpr>(E);
5639 if (!DRE || !isa<FunctionDecl>(DRE->getDecl()))
5640 return false;
5641
5642 return !S.checkAddressOfFunctionIsAvailable(
5643 cast<FunctionDecl>(DRE->getDecl()));
5644}
5645
5646/// Determine whether we can perform an elementwise array copy for this kind
5647/// of entity.
5648static bool canPerformArrayCopy(const InitializedEntity &Entity) {
5649 switch (Entity.getKind()) {
5650 case InitializedEntity::EK_LambdaCapture:
5651 // C++ [expr.prim.lambda]p24:
5652 // For array members, the array elements are direct-initialized in
5653 // increasing subscript order.
5654 return true;
5655
5656 case InitializedEntity::EK_Variable:
5657 // C++ [dcl.decomp]p1:
5658 // [...] each element is copy-initialized or direct-initialized from the
5659 // corresponding element of the assignment-expression [...]
5660 return isa<DecompositionDecl>(Entity.getDecl());
5661
5662 case InitializedEntity::EK_Member:
5663 // C++ [class.copy.ctor]p14:
5664 // - if the member is an array, each element is direct-initialized with
5665 // the corresponding subobject of x
5666 return Entity.isImplicitMemberInitializer();
5667
5668 case InitializedEntity::EK_ArrayElement:
5669 // All the above cases are intended to apply recursively, even though none
5670 // of them actually say that.
5671 if (auto *E = Entity.getParent())
5672 return canPerformArrayCopy(*E);
5673 break;
5674
5675 default:
5676 break;
5677 }
5678
5679 return false;
5680}
5681
5682void InitializationSequence::InitializeFrom(Sema &S,
5683 const InitializedEntity &Entity,
5684 const InitializationKind &Kind,
5685 MultiExprArg Args,
5686 bool TopLevelOfInitList,
5687 bool TreatUnavailableAsInvalid) {
5688 ASTContext &Context = S.Context;
5689
5690 // Eliminate non-overload placeholder types in the arguments. We
5691 // need to do this before checking whether types are dependent
5692 // because lowering a pseudo-object expression might well give us
5693 // something of dependent type.
5694 for (unsigned I = 0, E = Args.size(); I != E; ++I)
5695 if (Args[I]->getType()->isNonOverloadPlaceholderType()) {
5696 // FIXME: should we be doing this here?
5697 ExprResult result = S.CheckPlaceholderExpr(Args[I]);
5698 if (result.isInvalid()) {
5699 SetFailed(FK_PlaceholderType);
5700 return;
5701 }
5702 Args[I] = result.get();
5703 }
5704
5705 // C++0x [dcl.init]p16:
5706 // The semantics of initializers are as follows. The destination type is
5707 // the type of the object or reference being initialized and the source
5708 // type is the type of the initializer expression. The source type is not
5709 // defined when the initializer is a braced-init-list or when it is a
5710 // parenthesized list of expressions.
5711 QualType DestType = Entity.getType();
5712
5713 if (DestType->isDependentType() ||
5714 Expr::hasAnyTypeDependentArguments(Args)) {
5715 SequenceKind = DependentSequence;
5716 return;
5717 }
5718
5719 // Almost everything is a normal sequence.
5720 setSequenceKind(NormalSequence);
5721
5722 QualType SourceType;
5723 Expr *Initializer = nullptr;
5724 if (Args.size() == 1) {
5725 Initializer = Args[0];
5726 if (S.getLangOpts().ObjC) {
5727 if (S.CheckObjCBridgeRelatedConversions(Initializer->getBeginLoc(),
5728 DestType, Initializer->getType(),
5729 Initializer) ||
5730 S.CheckConversionToObjCLiteral(DestType, Initializer))
5731 Args[0] = Initializer;
5732 }
5733 if (!isa<InitListExpr>(Initializer))
5734 SourceType = Initializer->getType();
5735 }
5736
5737 // - If the initializer is a (non-parenthesized) braced-init-list, the
5738 // object is list-initialized (8.5.4).
5739 if (Kind.getKind() != InitializationKind::IK_Direct) {
5740 if (InitListExpr *InitList = dyn_cast_or_null<InitListExpr>(Initializer)) {
5741 TryListInitialization(S, Entity, Kind, InitList, *this,
5742 TreatUnavailableAsInvalid);
5743 return;
5744 }
5745 }
5746
5747 // - If the destination type is a reference type, see 8.5.3.
5748 if (DestType->isReferenceType()) {
5749 // C++0x [dcl.init.ref]p1:
5750 // A variable declared to be a T& or T&&, that is, "reference to type T"
5751 // (8.3.2), shall be initialized by an object, or function, of type T or
5752 // by an object that can be converted into a T.
5753 // (Therefore, multiple arguments are not permitted.)
5754 if (Args.size() != 1)
5755 SetFailed(FK_TooManyInitsForReference);
5756 // C++17 [dcl.init.ref]p5:
5757 // A reference [...] is initialized by an expression [...] as follows:
5758 // If the initializer is not an expression, presumably we should reject,
5759 // but the standard fails to actually say so.
5760 else if (isa<InitListExpr>(Args[0]))
5761 SetFailed(FK_ParenthesizedListInitForReference);
5762 else
5763 TryReferenceInitialization(S, Entity, Kind, Args[0], *this);
5764 return;
5765 }
5766
5767 // - If the initializer is (), the object is value-initialized.
5768 if (Kind.getKind() == InitializationKind::IK_Value ||
5769 (Kind.getKind() == InitializationKind::IK_Direct && Args.empty())) {
5770 TryValueInitialization(S, Entity, Kind, *this);
5771 return;
5772 }
5773
5774 // Handle default initialization.
5775 if (Kind.getKind() == InitializationKind::IK_Default) {
5776 TryDefaultInitialization(S, Entity, Kind, *this);
5777 return;
5778 }
5779
5780 // - If the destination type is an array of characters, an array of
5781 // char16_t, an array of char32_t, or an array of wchar_t, and the
5782 // initializer is a string literal, see 8.5.2.
5783 // - Otherwise, if the destination type is an array, the program is
5784 // ill-formed.
5785 if (const ArrayType *DestAT = Context.getAsArrayType(DestType)) {
5786 if (Initializer && isa<VariableArrayType>(DestAT)) {
5787 SetFailed(FK_VariableLengthArrayHasInitializer);
5788 return;
5789 }
5790
5791 if (Initializer) {
5792 switch (IsStringInit(Initializer, DestAT, Context)) {
5793 case SIF_None:
5794 TryStringLiteralInitialization(S, Entity, Kind, Initializer, *this);
5795 return;
5796 case SIF_NarrowStringIntoWideChar:
5797 SetFailed(FK_NarrowStringIntoWideCharArray);
5798 return;
5799 case SIF_WideStringIntoChar:
5800 SetFailed(FK_WideStringIntoCharArray);
5801 return;
5802 case SIF_IncompatWideStringIntoWideChar:
5803 SetFailed(FK_IncompatWideStringIntoWideChar);
5804 return;
5805 case SIF_PlainStringIntoUTF8Char:
5806 SetFailed(FK_PlainStringIntoUTF8Char);
5807 return;
5808 case SIF_UTF8StringIntoPlainChar:
5809 SetFailed(FK_UTF8StringIntoPlainChar);
5810 return;
5811 case SIF_Other:
5812 break;
5813 }
5814 }
5815
5816 // Some kinds of initialization permit an array to be initialized from
5817 // another array of the same type, and perform elementwise initialization.
5818 if (Initializer && isa<ConstantArrayType>(DestAT) &&
5819 S.Context.hasSameUnqualifiedType(Initializer->getType(),
5820 Entity.getType()) &&
5821 canPerformArrayCopy(Entity)) {
5822 // If source is a prvalue, use it directly.
5823 if (Initializer->getValueKind() == VK_RValue) {
5824 AddArrayInitStep(DestType, /*IsGNUExtension*/false);
5825 return;
5826 }
5827
5828 // Emit element-at-a-time copy loop.
5829 InitializedEntity Element =
5830 InitializedEntity::InitializeElement(S.Context, 0, Entity);
5831 QualType InitEltT =
5832 Context.getAsArrayType(Initializer->getType())->getElementType();
5833 OpaqueValueExpr OVE(Initializer->getExprLoc(), InitEltT,
5834 Initializer->getValueKind(),
5835 Initializer->getObjectKind());
5836 Expr *OVEAsExpr = &OVE;
5837 InitializeFrom(S, Element, Kind, OVEAsExpr, TopLevelOfInitList,
5838 TreatUnavailableAsInvalid);
5839 if (!Failed())
5840 AddArrayInitLoopStep(Entity.getType(), InitEltT);
5841 return;
5842 }
5843
5844 // Note: as an GNU C extension, we allow initialization of an
5845 // array from a compound literal that creates an array of the same
5846 // type, so long as the initializer has no side effects.
5847 if (!S.getLangOpts().CPlusPlus && Initializer &&
5848 isa<CompoundLiteralExpr>(Initializer->IgnoreParens()) &&
5849 Initializer->getType()->isArrayType()) {
5850 const ArrayType *SourceAT
5851 = Context.getAsArrayType(Initializer->getType());
5852 if (!hasCompatibleArrayTypes(S.Context, DestAT, SourceAT))
5853 SetFailed(FK_ArrayTypeMismatch);
5854 else if (Initializer->HasSideEffects(S.Context))
5855 SetFailed(FK_NonConstantArrayInit);
5856 else {
5857 AddArrayInitStep(DestType, /*IsGNUExtension*/true);
5858 }
5859 }
5860 // Note: as a GNU C++ extension, we allow list-initialization of a
5861 // class member of array type from a parenthesized initializer list.
5862 else if (S.getLangOpts().CPlusPlus &&
5863 Entity.getKind() == InitializedEntity::EK_Member &&
5864 Initializer && isa<InitListExpr>(Initializer)) {
5865 TryListInitialization(S, Entity, Kind, cast<InitListExpr>(Initializer),
5866 *this, TreatUnavailableAsInvalid);
5867 AddParenthesizedArrayInitStep(DestType);
5868 } else if (DestAT->getElementType()->isCharType())
5869 SetFailed(FK_ArrayNeedsInitListOrStringLiteral);
5870 else if (IsWideCharCompatible(DestAT->getElementType(), Context))
5871 SetFailed(FK_ArrayNeedsInitListOrWideStringLiteral);
5872 else
5873 SetFailed(FK_ArrayNeedsInitList);
5874
5875 return;
5876 }
5877
5878 // Determine whether we should consider writeback conversions for
5879 // Objective-C ARC.
5880 bool allowObjCWritebackConversion = S.getLangOpts().ObjCAutoRefCount &&
5881 Entity.isParameterKind();
5882
5883 if (TryOCLSamplerInitialization(S, *this, DestType, Initializer))
5884 return;
5885
5886 // We're at the end of the line for C: it's either a write-back conversion
5887 // or it's a C assignment. There's no need to check anything else.
5888 if (!S.getLangOpts().CPlusPlus) {
5889 // If allowed, check whether this is an Objective-C writeback conversion.
5890 if (allowObjCWritebackConversion &&
5891 tryObjCWritebackConversion(S, *this, Entity, Initializer)) {
5892 return;
5893 }
5894
5895 if (TryOCLZeroOpaqueTypeInitialization(S, *this, DestType, Initializer))
5896 return;
5897
5898 // Handle initialization in C
5899 AddCAssignmentStep(DestType);
5900 MaybeProduceObjCObject(S, *this, Entity);
5901 return;
5902 }
5903
5904 assert(S.getLangOpts().CPlusPlus)((S.getLangOpts().CPlusPlus) ? static_cast<void> (0) : __assert_fail
("S.getLangOpts().CPlusPlus", "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5904, __PRETTY_FUNCTION__))
;
5905
5906 // - If the destination type is a (possibly cv-qualified) class type:
5907 if (DestType->isRecordType()) {
5908 // - If the initialization is direct-initialization, or if it is
5909 // copy-initialization where the cv-unqualified version of the
5910 // source type is the same class as, or a derived class of, the
5911 // class of the destination, constructors are considered. [...]
5912 if (Kind.getKind() == InitializationKind::IK_Direct ||
5913 (Kind.getKind() == InitializationKind::IK_Copy &&
5914 (Context.hasSameUnqualifiedType(SourceType, DestType) ||
5915 S.IsDerivedFrom(Initializer->getBeginLoc(), SourceType, DestType))))
5916 TryConstructorInitialization(S, Entity, Kind, Args,
5917 DestType, DestType, *this);
5918 // - Otherwise (i.e., for the remaining copy-initialization cases),
5919 // user-defined conversion sequences that can convert from the source
5920 // type to the destination type or (when a conversion function is
5921 // used) to a derived class thereof are enumerated as described in
5922 // 13.3.1.4, and the best one is chosen through overload resolution
5923 // (13.3).
5924 else
5925 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
5926 TopLevelOfInitList);
5927 return;
5928 }
5929
5930 assert(Args.size() >= 1 && "Zero-argument case handled above")((Args.size() >= 1 && "Zero-argument case handled above"
) ? static_cast<void> (0) : __assert_fail ("Args.size() >= 1 && \"Zero-argument case handled above\""
, "/build/llvm-toolchain-snapshot-13~++20210223111116+16ede0956cb1/clang/lib/Sema/SemaInit.cpp"
, 5930, __PRETTY_FUNCTION__))
;
5931
5932 // The remaining cases all need a source type.
5933 if (Args.size() > 1) {
5934 SetFailed(FK_TooManyInitsForScalar);
5935 return;
5936 } else if (isa<InitListExpr>(Args[0])) {
5937 SetFailed(FK_ParenthesizedListInitForScalar);
5938 return;
5939 }
5940
5941 // - Otherwise, if the source type is a (possibly cv-qualified) class
5942 // type, conversion functions are considered.
5943 if (!SourceType.isNull() && SourceType->isRecordType()) {
5944 // For a conversion to _Atomic(T) from either T or a class type derived
5945 // from T, initialize the T object then convert to _Atomic type.
5946 bool NeedAtomicConversion = false;
5947 if (const AtomicType *Atomic = DestType->getAs<AtomicType>()) {
5948 if (Context.hasSameUnqualifiedType(SourceType, Atomic->getValueType()) ||
5949 S.IsDerivedFrom(Initializer->getBeginLoc(), SourceType,
5950 Atomic->getValueType())) {
5951 DestType = Atomic->getValueType();
5952 NeedAtomicConversion = true;
5953 }
5954 }
5955
5956 TryUserDefinedConversion(S, DestType, Kind, Initializer, *this,
5957 TopLevelOfInitList);
5958 MaybeProduceObjCObject(S, *this, Entity);
5959 if (!Failed() && NeedAtomicConversion)
5960 AddAtomicConversionStep(Entity.getType());
5961 return;
5962 }
5963
5964 // - Otherwise, if the initialization is direct-initialization, the source
5965 // type is std::nullptr_t, and the destination type is bool, the initial
5966 // value of the object being initialized is false.
5967 if (!SourceType.isNull() && SourceType->isNullPtrType() &&
5968 DestType->isBooleanType() &&
5969 Kind.getKind() == InitializationKind::IK_Direct) {
5970 AddConversionSequenceStep(
5971 ImplicitConversionSequence::getNullptrToBool(SourceType, DestType,
5972 Initializer->isGLValue()),
5973 DestType);
5974 return;
5975 }
5976
5977 // - Otherwise, the initial value of the object being initialized is the
5978 // (possibly converted) value of the initializer expression. Standard
5979 // conversions (Clause 4) will be used, if necessary, to convert the
5980 // initializer expression to the cv-unqualified version of the
5981 // destination type; no user-defined conversions are considered.
5982
5983 ImplicitConversionSequence ICS
5984 = S.TryImplicitConversion(Initializer, DestType,
5985 /*SuppressUserConversions*/true,
5986 Sema::AllowedExplicit::None,
5987 /*InOverloadResolution*/ false,
5988 /*CStyle=*/Kind.isCStyleOrFunctionalCast(),
5989 allowObjCWritebackConversion);
5990
5991 if (ICS.isStandard() &&
5992 ICS.Standard.Second == ICK_Writeback_Conversion) {
5993 // Objective-C ARC writeback conversion.
5994
5995 // We should copy unless we're passing to an argument explicitly
5996 // marked 'out'.
5997 bool ShouldCopy = true;
5998 if (ParmVarDecl *Param = cast_or_null<ParmVarDecl>(Entity.getDecl()))
5999 ShouldCopy = (Param->getObjCDeclQualifier() != ParmVarDecl::OBJC_TQ_Out);
6000
6001 // If there was an lvalue adjustment, add it as a separate conversion.
6002 if (ICS.Standard.First == ICK_Array_To_Pointer ||
6003 ICS.Standard.First == ICK_Lvalue_To_Rvalue) {
6004 ImplicitConversionSequence LvalueICS;
6005 LvalueICS.setStandard();
6006 LvalueICS.Standard.setAsIdentityConversion();
6007 LvalueICS.Standard.setAllToTypes(ICS.Standard.getToType(0));
6008 LvalueICS.Standard.First = ICS.Standard.First;
6009 AddConversionSequenceStep(LvalueICS, ICS.Standard.getToType(0));
6010 }