Bug Summary

File:build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/clang/lib/Sema/SemaDeclCXX.cpp
Warning:line 1342, column 25
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name SemaDeclCXX.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/build-llvm -resource-dir /usr/lib/llvm-16/lib/clang/16.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/clang/lib/Sema -I /build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/clang/include -I tools/clang/include -I include -I /build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/llvm/include -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-16/lib/clang/16.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/build-llvm=build-llvm -fmacro-prefix-map=/build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/= -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/build-llvm=build-llvm -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/= -O3 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-misleading-indentation -std=c++17 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/build-llvm -fdebug-prefix-map=/build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/build-llvm=build-llvm -fdebug-prefix-map=/build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2022-10-03-140002-15933-1 -x c++ /build/llvm-toolchain-snapshot-16~++20221003111214+1fa2019828ca/clang/lib/Sema/SemaDeclCXX.cpp
1//===------ SemaDeclCXX.cpp - Semantic Analysis for C++ Declarations ------===//
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 C++ declarations.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/AST/ASTConsumer.h"
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/ASTLambda.h"
16#include "clang/AST/ASTMutationListener.h"
17#include "clang/AST/CXXInheritance.h"
18#include "clang/AST/CharUnits.h"
19#include "clang/AST/ComparisonCategories.h"
20#include "clang/AST/DeclTemplate.h"
21#include "clang/AST/EvaluatedExprVisitor.h"
22#include "clang/AST/ExprCXX.h"
23#include "clang/AST/RecordLayout.h"
24#include "clang/AST/RecursiveASTVisitor.h"
25#include "clang/AST/StmtVisitor.h"
26#include "clang/AST/TypeLoc.h"
27#include "clang/AST/TypeOrdering.h"
28#include "clang/Basic/AttributeCommonInfo.h"
29#include "clang/Basic/PartialDiagnostic.h"
30#include "clang/Basic/Specifiers.h"
31#include "clang/Basic/TargetInfo.h"
32#include "clang/Lex/LiteralSupport.h"
33#include "clang/Lex/Preprocessor.h"
34#include "clang/Sema/CXXFieldCollector.h"
35#include "clang/Sema/DeclSpec.h"
36#include "clang/Sema/Initialization.h"
37#include "clang/Sema/Lookup.h"
38#include "clang/Sema/ParsedTemplate.h"
39#include "clang/Sema/Scope.h"
40#include "clang/Sema/ScopeInfo.h"
41#include "clang/Sema/SemaInternal.h"
42#include "clang/Sema/Template.h"
43#include "llvm/ADT/ScopeExit.h"
44#include "llvm/ADT/SmallString.h"
45#include "llvm/ADT/STLExtras.h"
46#include "llvm/ADT/StringExtras.h"
47#include <map>
48#include <set>
49
50using namespace clang;
51
52//===----------------------------------------------------------------------===//
53// CheckDefaultArgumentVisitor
54//===----------------------------------------------------------------------===//
55
56namespace {
57/// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses
58/// the default argument of a parameter to determine whether it
59/// contains any ill-formed subexpressions. For example, this will
60/// diagnose the use of local variables or parameters within the
61/// default argument expression.
62class CheckDefaultArgumentVisitor
63 : public ConstStmtVisitor<CheckDefaultArgumentVisitor, bool> {
64 Sema &S;
65 const Expr *DefaultArg;
66
67public:
68 CheckDefaultArgumentVisitor(Sema &S, const Expr *DefaultArg)
69 : S(S), DefaultArg(DefaultArg) {}
70
71 bool VisitExpr(const Expr *Node);
72 bool VisitDeclRefExpr(const DeclRefExpr *DRE);
73 bool VisitCXXThisExpr(const CXXThisExpr *ThisE);
74 bool VisitLambdaExpr(const LambdaExpr *Lambda);
75 bool VisitPseudoObjectExpr(const PseudoObjectExpr *POE);
76};
77
78/// VisitExpr - Visit all of the children of this expression.
79bool CheckDefaultArgumentVisitor::VisitExpr(const Expr *Node) {
80 bool IsInvalid = false;
81 for (const Stmt *SubStmt : Node->children())
82 IsInvalid |= Visit(SubStmt);
83 return IsInvalid;
84}
85
86/// VisitDeclRefExpr - Visit a reference to a declaration, to
87/// determine whether this declaration can be used in the default
88/// argument expression.
89bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(const DeclRefExpr *DRE) {
90 const NamedDecl *Decl = DRE->getDecl();
91 if (const auto *Param = dyn_cast<ParmVarDecl>(Decl)) {
92 // C++ [dcl.fct.default]p9:
93 // [...] parameters of a function shall not be used in default
94 // argument expressions, even if they are not evaluated. [...]
95 //
96 // C++17 [dcl.fct.default]p9 (by CWG 2082):
97 // [...] A parameter shall not appear as a potentially-evaluated
98 // expression in a default argument. [...]
99 //
100 if (DRE->isNonOdrUse() != NOUR_Unevaluated)
101 return S.Diag(DRE->getBeginLoc(),
102 diag::err_param_default_argument_references_param)
103 << Param->getDeclName() << DefaultArg->getSourceRange();
104 } else if (const auto *VDecl = dyn_cast<VarDecl>(Decl)) {
105 // C++ [dcl.fct.default]p7:
106 // Local variables shall not be used in default argument
107 // expressions.
108 //
109 // C++17 [dcl.fct.default]p7 (by CWG 2082):
110 // A local variable shall not appear as a potentially-evaluated
111 // expression in a default argument.
112 //
113 // C++20 [dcl.fct.default]p7 (DR as part of P0588R1, see also CWG 2346):
114 // Note: A local variable cannot be odr-used (6.3) in a default argument.
115 //
116 if (VDecl->isLocalVarDecl() && !DRE->isNonOdrUse())
117 return S.Diag(DRE->getBeginLoc(),
118 diag::err_param_default_argument_references_local)
119 << VDecl->getDeclName() << DefaultArg->getSourceRange();
120 }
121
122 return false;
123}
124
125/// VisitCXXThisExpr - Visit a C++ "this" expression.
126bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(const CXXThisExpr *ThisE) {
127 // C++ [dcl.fct.default]p8:
128 // The keyword this shall not be used in a default argument of a
129 // member function.
130 return S.Diag(ThisE->getBeginLoc(),
131 diag::err_param_default_argument_references_this)
132 << ThisE->getSourceRange();
133}
134
135bool CheckDefaultArgumentVisitor::VisitPseudoObjectExpr(
136 const PseudoObjectExpr *POE) {
137 bool Invalid = false;
138 for (const Expr *E : POE->semantics()) {
139 // Look through bindings.
140 if (const auto *OVE = dyn_cast<OpaqueValueExpr>(E)) {
141 E = OVE->getSourceExpr();
142 assert(E && "pseudo-object binding without source expression?")(static_cast <bool> (E && "pseudo-object binding without source expression?"
) ? void (0) : __assert_fail ("E && \"pseudo-object binding without source expression?\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 142, __extension__ __PRETTY_FUNCTION__
))
;
143 }
144
145 Invalid |= Visit(E);
146 }
147 return Invalid;
148}
149
150bool CheckDefaultArgumentVisitor::VisitLambdaExpr(const LambdaExpr *Lambda) {
151 // C++11 [expr.lambda.prim]p13:
152 // A lambda-expression appearing in a default argument shall not
153 // implicitly or explicitly capture any entity.
154 if (Lambda->capture_begin() == Lambda->capture_end())
155 return false;
156
157 return S.Diag(Lambda->getBeginLoc(), diag::err_lambda_capture_default_arg);
158}
159} // namespace
160
161void
162Sema::ImplicitExceptionSpecification::CalledDecl(SourceLocation CallLoc,
163 const CXXMethodDecl *Method) {
164 // If we have an MSAny spec already, don't bother.
165 if (!Method || ComputedEST == EST_MSAny)
166 return;
167
168 const FunctionProtoType *Proto
169 = Method->getType()->getAs<FunctionProtoType>();
170 Proto = Self->ResolveExceptionSpec(CallLoc, Proto);
171 if (!Proto)
172 return;
173
174 ExceptionSpecificationType EST = Proto->getExceptionSpecType();
175
176 // If we have a throw-all spec at this point, ignore the function.
177 if (ComputedEST == EST_None)
178 return;
179
180 if (EST == EST_None && Method->hasAttr<NoThrowAttr>())
181 EST = EST_BasicNoexcept;
182
183 switch (EST) {
184 case EST_Unparsed:
185 case EST_Uninstantiated:
186 case EST_Unevaluated:
187 llvm_unreachable("should not see unresolved exception specs here")::llvm::llvm_unreachable_internal("should not see unresolved exception specs here"
, "clang/lib/Sema/SemaDeclCXX.cpp", 187)
;
188
189 // If this function can throw any exceptions, make a note of that.
190 case EST_MSAny:
191 case EST_None:
192 // FIXME: Whichever we see last of MSAny and None determines our result.
193 // We should make a consistent, order-independent choice here.
194 ClearExceptions();
195 ComputedEST = EST;
196 return;
197 case EST_NoexceptFalse:
198 ClearExceptions();
199 ComputedEST = EST_None;
200 return;
201 // FIXME: If the call to this decl is using any of its default arguments, we
202 // need to search them for potentially-throwing calls.
203 // If this function has a basic noexcept, it doesn't affect the outcome.
204 case EST_BasicNoexcept:
205 case EST_NoexceptTrue:
206 case EST_NoThrow:
207 return;
208 // If we're still at noexcept(true) and there's a throw() callee,
209 // change to that specification.
210 case EST_DynamicNone:
211 if (ComputedEST == EST_BasicNoexcept)
212 ComputedEST = EST_DynamicNone;
213 return;
214 case EST_DependentNoexcept:
215 llvm_unreachable(::llvm::llvm_unreachable_internal("should not generate implicit declarations for dependent cases"
, "clang/lib/Sema/SemaDeclCXX.cpp", 216)
216 "should not generate implicit declarations for dependent cases")::llvm::llvm_unreachable_internal("should not generate implicit declarations for dependent cases"
, "clang/lib/Sema/SemaDeclCXX.cpp", 216)
;
217 case EST_Dynamic:
218 break;
219 }
220 assert(EST == EST_Dynamic && "EST case not considered earlier.")(static_cast <bool> (EST == EST_Dynamic && "EST case not considered earlier."
) ? void (0) : __assert_fail ("EST == EST_Dynamic && \"EST case not considered earlier.\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 220, __extension__ __PRETTY_FUNCTION__
))
;
221 assert(ComputedEST != EST_None &&(static_cast <bool> (ComputedEST != EST_None &&
"Shouldn't collect exceptions when throw-all is guaranteed."
) ? void (0) : __assert_fail ("ComputedEST != EST_None && \"Shouldn't collect exceptions when throw-all is guaranteed.\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 222, __extension__ __PRETTY_FUNCTION__
))
222 "Shouldn't collect exceptions when throw-all is guaranteed.")(static_cast <bool> (ComputedEST != EST_None &&
"Shouldn't collect exceptions when throw-all is guaranteed."
) ? void (0) : __assert_fail ("ComputedEST != EST_None && \"Shouldn't collect exceptions when throw-all is guaranteed.\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 222, __extension__ __PRETTY_FUNCTION__
))
;
223 ComputedEST = EST_Dynamic;
224 // Record the exceptions in this function's exception specification.
225 for (const auto &E : Proto->exceptions())
226 if (ExceptionsSeen.insert(Self->Context.getCanonicalType(E)).second)
227 Exceptions.push_back(E);
228}
229
230void Sema::ImplicitExceptionSpecification::CalledStmt(Stmt *S) {
231 if (!S || ComputedEST == EST_MSAny)
232 return;
233
234 // FIXME:
235 //
236 // C++0x [except.spec]p14:
237 // [An] implicit exception-specification specifies the type-id T if and
238 // only if T is allowed by the exception-specification of a function directly
239 // invoked by f's implicit definition; f shall allow all exceptions if any
240 // function it directly invokes allows all exceptions, and f shall allow no
241 // exceptions if every function it directly invokes allows no exceptions.
242 //
243 // Note in particular that if an implicit exception-specification is generated
244 // for a function containing a throw-expression, that specification can still
245 // be noexcept(true).
246 //
247 // Note also that 'directly invoked' is not defined in the standard, and there
248 // is no indication that we should only consider potentially-evaluated calls.
249 //
250 // Ultimately we should implement the intent of the standard: the exception
251 // specification should be the set of exceptions which can be thrown by the
252 // implicit definition. For now, we assume that any non-nothrow expression can
253 // throw any exception.
254
255 if (Self->canThrow(S))
256 ComputedEST = EST_None;
257}
258
259ExprResult Sema::ConvertParamDefaultArgument(ParmVarDecl *Param, Expr *Arg,
260 SourceLocation EqualLoc) {
261 if (RequireCompleteType(Param->getLocation(), Param->getType(),
262 diag::err_typecheck_decl_incomplete_type))
263 return true;
264
265 // C++ [dcl.fct.default]p5
266 // A default argument expression is implicitly converted (clause
267 // 4) to the parameter type. The default argument expression has
268 // the same semantic constraints as the initializer expression in
269 // a declaration of a variable of the parameter type, using the
270 // copy-initialization semantics (8.5).
271 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
272 Param);
273 InitializationKind Kind = InitializationKind::CreateCopy(Param->getLocation(),
274 EqualLoc);
275 InitializationSequence InitSeq(*this, Entity, Kind, Arg);
276 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Arg);
277 if (Result.isInvalid())
278 return true;
279 Arg = Result.getAs<Expr>();
280
281 CheckCompletedExpr(Arg, EqualLoc);
282 Arg = MaybeCreateExprWithCleanups(Arg);
283
284 return Arg;
285}
286
287void Sema::SetParamDefaultArgument(ParmVarDecl *Param, Expr *Arg,
288 SourceLocation EqualLoc) {
289 // Add the default argument to the parameter
290 Param->setDefaultArg(Arg);
291
292 // We have already instantiated this parameter; provide each of the
293 // instantiations with the uninstantiated default argument.
294 UnparsedDefaultArgInstantiationsMap::iterator InstPos
295 = UnparsedDefaultArgInstantiations.find(Param);
296 if (InstPos != UnparsedDefaultArgInstantiations.end()) {
297 for (unsigned I = 0, N = InstPos->second.size(); I != N; ++I)
298 InstPos->second[I]->setUninstantiatedDefaultArg(Arg);
299
300 // We're done tracking this parameter's instantiations.
301 UnparsedDefaultArgInstantiations.erase(InstPos);
302 }
303}
304
305/// ActOnParamDefaultArgument - Check whether the default argument
306/// provided for a function parameter is well-formed. If so, attach it
307/// to the parameter declaration.
308void
309Sema::ActOnParamDefaultArgument(Decl *param, SourceLocation EqualLoc,
310 Expr *DefaultArg) {
311 if (!param || !DefaultArg)
312 return;
313
314 ParmVarDecl *Param = cast<ParmVarDecl>(param);
315 UnparsedDefaultArgLocs.erase(Param);
316
317 auto Fail = [&] {
318 Param->setInvalidDecl();
319 Param->setDefaultArg(new (Context) OpaqueValueExpr(
320 EqualLoc, Param->getType().getNonReferenceType(), VK_PRValue));
321 };
322
323 // Default arguments are only permitted in C++
324 if (!getLangOpts().CPlusPlus) {
325 Diag(EqualLoc, diag::err_param_default_argument)
326 << DefaultArg->getSourceRange();
327 return Fail();
328 }
329
330 // Check for unexpanded parameter packs.
331 if (DiagnoseUnexpandedParameterPack(DefaultArg, UPPC_DefaultArgument)) {
332 return Fail();
333 }
334
335 // C++11 [dcl.fct.default]p3
336 // A default argument expression [...] shall not be specified for a
337 // parameter pack.
338 if (Param->isParameterPack()) {
339 Diag(EqualLoc, diag::err_param_default_argument_on_parameter_pack)
340 << DefaultArg->getSourceRange();
341 // Recover by discarding the default argument.
342 Param->setDefaultArg(nullptr);
343 return;
344 }
345
346 ExprResult Result = ConvertParamDefaultArgument(Param, DefaultArg, EqualLoc);
347 if (Result.isInvalid())
348 return Fail();
349
350 DefaultArg = Result.getAs<Expr>();
351
352 // Check that the default argument is well-formed
353 CheckDefaultArgumentVisitor DefaultArgChecker(*this, DefaultArg);
354 if (DefaultArgChecker.Visit(DefaultArg))
355 return Fail();
356
357 SetParamDefaultArgument(Param, DefaultArg, EqualLoc);
358}
359
360/// ActOnParamUnparsedDefaultArgument - We've seen a default
361/// argument for a function parameter, but we can't parse it yet
362/// because we're inside a class definition. Note that this default
363/// argument will be parsed later.
364void Sema::ActOnParamUnparsedDefaultArgument(Decl *param,
365 SourceLocation EqualLoc,
366 SourceLocation ArgLoc) {
367 if (!param)
368 return;
369
370 ParmVarDecl *Param = cast<ParmVarDecl>(param);
371 Param->setUnparsedDefaultArg();
372 UnparsedDefaultArgLocs[Param] = ArgLoc;
373}
374
375/// ActOnParamDefaultArgumentError - Parsing or semantic analysis of
376/// the default argument for the parameter param failed.
377void Sema::ActOnParamDefaultArgumentError(Decl *param,
378 SourceLocation EqualLoc) {
379 if (!param)
380 return;
381
382 ParmVarDecl *Param = cast<ParmVarDecl>(param);
383 Param->setInvalidDecl();
384 UnparsedDefaultArgLocs.erase(Param);
385 Param->setDefaultArg(new (Context) OpaqueValueExpr(
386 EqualLoc, Param->getType().getNonReferenceType(), VK_PRValue));
387}
388
389/// CheckExtraCXXDefaultArguments - Check for any extra default
390/// arguments in the declarator, which is not a function declaration
391/// or definition and therefore is not permitted to have default
392/// arguments. This routine should be invoked for every declarator
393/// that is not a function declaration or definition.
394void Sema::CheckExtraCXXDefaultArguments(Declarator &D) {
395 // C++ [dcl.fct.default]p3
396 // A default argument expression shall be specified only in the
397 // parameter-declaration-clause of a function declaration or in a
398 // template-parameter (14.1). It shall not be specified for a
399 // parameter pack. If it is specified in a
400 // parameter-declaration-clause, it shall not occur within a
401 // declarator or abstract-declarator of a parameter-declaration.
402 bool MightBeFunction = D.isFunctionDeclarationContext();
403 for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
404 DeclaratorChunk &chunk = D.getTypeObject(i);
405 if (chunk.Kind == DeclaratorChunk::Function) {
406 if (MightBeFunction) {
407 // This is a function declaration. It can have default arguments, but
408 // keep looking in case its return type is a function type with default
409 // arguments.
410 MightBeFunction = false;
411 continue;
412 }
413 for (unsigned argIdx = 0, e = chunk.Fun.NumParams; argIdx != e;
414 ++argIdx) {
415 ParmVarDecl *Param = cast<ParmVarDecl>(chunk.Fun.Params[argIdx].Param);
416 if (Param->hasUnparsedDefaultArg()) {
417 std::unique_ptr<CachedTokens> Toks =
418 std::move(chunk.Fun.Params[argIdx].DefaultArgTokens);
419 SourceRange SR;
420 if (Toks->size() > 1)
421 SR = SourceRange((*Toks)[1].getLocation(),
422 Toks->back().getLocation());
423 else
424 SR = UnparsedDefaultArgLocs[Param];
425 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
426 << SR;
427 } else if (Param->getDefaultArg()) {
428 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
429 << Param->getDefaultArg()->getSourceRange();
430 Param->setDefaultArg(nullptr);
431 }
432 }
433 } else if (chunk.Kind != DeclaratorChunk::Paren) {
434 MightBeFunction = false;
435 }
436 }
437}
438
439static bool functionDeclHasDefaultArgument(const FunctionDecl *FD) {
440 return llvm::any_of(FD->parameters(), [](ParmVarDecl *P) {
441 return P->hasDefaultArg() && !P->hasInheritedDefaultArg();
442 });
443}
444
445/// MergeCXXFunctionDecl - Merge two declarations of the same C++
446/// function, once we already know that they have the same
447/// type. Subroutine of MergeFunctionDecl. Returns true if there was an
448/// error, false otherwise.
449bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old,
450 Scope *S) {
451 bool Invalid = false;
452
453 // The declaration context corresponding to the scope is the semantic
454 // parent, unless this is a local function declaration, in which case
455 // it is that surrounding function.
456 DeclContext *ScopeDC = New->isLocalExternDecl()
457 ? New->getLexicalDeclContext()
458 : New->getDeclContext();
459
460 // Find the previous declaration for the purpose of default arguments.
461 FunctionDecl *PrevForDefaultArgs = Old;
462 for (/**/; PrevForDefaultArgs;
463 // Don't bother looking back past the latest decl if this is a local
464 // extern declaration; nothing else could work.
465 PrevForDefaultArgs = New->isLocalExternDecl()
466 ? nullptr
467 : PrevForDefaultArgs->getPreviousDecl()) {
468 // Ignore hidden declarations.
469 if (!LookupResult::isVisible(*this, PrevForDefaultArgs))
470 continue;
471
472 if (S && !isDeclInScope(PrevForDefaultArgs, ScopeDC, S) &&
473 !New->isCXXClassMember()) {
474 // Ignore default arguments of old decl if they are not in
475 // the same scope and this is not an out-of-line definition of
476 // a member function.
477 continue;
478 }
479
480 if (PrevForDefaultArgs->isLocalExternDecl() != New->isLocalExternDecl()) {
481 // If only one of these is a local function declaration, then they are
482 // declared in different scopes, even though isDeclInScope may think
483 // they're in the same scope. (If both are local, the scope check is
484 // sufficient, and if neither is local, then they are in the same scope.)
485 continue;
486 }
487
488 // We found the right previous declaration.
489 break;
490 }
491
492 // C++ [dcl.fct.default]p4:
493 // For non-template functions, default arguments can be added in
494 // later declarations of a function in the same
495 // scope. Declarations in different scopes have completely
496 // distinct sets of default arguments. That is, declarations in
497 // inner scopes do not acquire default arguments from
498 // declarations in outer scopes, and vice versa. In a given
499 // function declaration, all parameters subsequent to a
500 // parameter with a default argument shall have default
501 // arguments supplied in this or previous declarations. A
502 // default argument shall not be redefined by a later
503 // declaration (not even to the same value).
504 //
505 // C++ [dcl.fct.default]p6:
506 // Except for member functions of class templates, the default arguments
507 // in a member function definition that appears outside of the class
508 // definition are added to the set of default arguments provided by the
509 // member function declaration in the class definition.
510 for (unsigned p = 0, NumParams = PrevForDefaultArgs
511 ? PrevForDefaultArgs->getNumParams()
512 : 0;
513 p < NumParams; ++p) {
514 ParmVarDecl *OldParam = PrevForDefaultArgs->getParamDecl(p);
515 ParmVarDecl *NewParam = New->getParamDecl(p);
516
517 bool OldParamHasDfl = OldParam ? OldParam->hasDefaultArg() : false;
518 bool NewParamHasDfl = NewParam->hasDefaultArg();
519
520 if (OldParamHasDfl && NewParamHasDfl) {
521 unsigned DiagDefaultParamID =
522 diag::err_param_default_argument_redefinition;
523
524 // MSVC accepts that default parameters be redefined for member functions
525 // of template class. The new default parameter's value is ignored.
526 Invalid = true;
527 if (getLangOpts().MicrosoftExt) {
528 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(New);
529 if (MD && MD->getParent()->getDescribedClassTemplate()) {
530 // Merge the old default argument into the new parameter.
531 NewParam->setHasInheritedDefaultArg();
532 if (OldParam->hasUninstantiatedDefaultArg())
533 NewParam->setUninstantiatedDefaultArg(
534 OldParam->getUninstantiatedDefaultArg());
535 else
536 NewParam->setDefaultArg(OldParam->getInit());
537 DiagDefaultParamID = diag::ext_param_default_argument_redefinition;
538 Invalid = false;
539 }
540 }
541
542 // FIXME: If we knew where the '=' was, we could easily provide a fix-it
543 // hint here. Alternatively, we could walk the type-source information
544 // for NewParam to find the last source location in the type... but it
545 // isn't worth the effort right now. This is the kind of test case that
546 // is hard to get right:
547 // int f(int);
548 // void g(int (*fp)(int) = f);
549 // void g(int (*fp)(int) = &f);
550 Diag(NewParam->getLocation(), DiagDefaultParamID)
551 << NewParam->getDefaultArgRange();
552
553 // Look for the function declaration where the default argument was
554 // actually written, which may be a declaration prior to Old.
555 for (auto Older = PrevForDefaultArgs;
556 OldParam->hasInheritedDefaultArg(); /**/) {
557 Older = Older->getPreviousDecl();
558 OldParam = Older->getParamDecl(p);
559 }
560
561 Diag(OldParam->getLocation(), diag::note_previous_definition)
562 << OldParam->getDefaultArgRange();
563 } else if (OldParamHasDfl) {
564 // Merge the old default argument into the new parameter unless the new
565 // function is a friend declaration in a template class. In the latter
566 // case the default arguments will be inherited when the friend
567 // declaration will be instantiated.
568 if (New->getFriendObjectKind() == Decl::FOK_None ||
569 !New->getLexicalDeclContext()->isDependentContext()) {
570 // It's important to use getInit() here; getDefaultArg()
571 // strips off any top-level ExprWithCleanups.
572 NewParam->setHasInheritedDefaultArg();
573 if (OldParam->hasUnparsedDefaultArg())
574 NewParam->setUnparsedDefaultArg();
575 else if (OldParam->hasUninstantiatedDefaultArg())
576 NewParam->setUninstantiatedDefaultArg(
577 OldParam->getUninstantiatedDefaultArg());
578 else
579 NewParam->setDefaultArg(OldParam->getInit());
580 }
581 } else if (NewParamHasDfl) {
582 if (New->getDescribedFunctionTemplate()) {
583 // Paragraph 4, quoted above, only applies to non-template functions.
584 Diag(NewParam->getLocation(),
585 diag::err_param_default_argument_template_redecl)
586 << NewParam->getDefaultArgRange();
587 Diag(PrevForDefaultArgs->getLocation(),
588 diag::note_template_prev_declaration)
589 << false;
590 } else if (New->getTemplateSpecializationKind()
591 != TSK_ImplicitInstantiation &&
592 New->getTemplateSpecializationKind() != TSK_Undeclared) {
593 // C++ [temp.expr.spec]p21:
594 // Default function arguments shall not be specified in a declaration
595 // or a definition for one of the following explicit specializations:
596 // - the explicit specialization of a function template;
597 // - the explicit specialization of a member function template;
598 // - the explicit specialization of a member function of a class
599 // template where the class template specialization to which the
600 // member function specialization belongs is implicitly
601 // instantiated.
602 Diag(NewParam->getLocation(), diag::err_template_spec_default_arg)
603 << (New->getTemplateSpecializationKind() ==TSK_ExplicitSpecialization)
604 << New->getDeclName()
605 << NewParam->getDefaultArgRange();
606 } else if (New->getDeclContext()->isDependentContext()) {
607 // C++ [dcl.fct.default]p6 (DR217):
608 // Default arguments for a member function of a class template shall
609 // be specified on the initial declaration of the member function
610 // within the class template.
611 //
612 // Reading the tea leaves a bit in DR217 and its reference to DR205
613 // leads me to the conclusion that one cannot add default function
614 // arguments for an out-of-line definition of a member function of a
615 // dependent type.
616 int WhichKind = 2;
617 if (CXXRecordDecl *Record
618 = dyn_cast<CXXRecordDecl>(New->getDeclContext())) {
619 if (Record->getDescribedClassTemplate())
620 WhichKind = 0;
621 else if (isa<ClassTemplatePartialSpecializationDecl>(Record))
622 WhichKind = 1;
623 else
624 WhichKind = 2;
625 }
626
627 Diag(NewParam->getLocation(),
628 diag::err_param_default_argument_member_template_redecl)
629 << WhichKind
630 << NewParam->getDefaultArgRange();
631 }
632 }
633 }
634
635 // DR1344: If a default argument is added outside a class definition and that
636 // default argument makes the function a special member function, the program
637 // is ill-formed. This can only happen for constructors.
638 if (isa<CXXConstructorDecl>(New) &&
639 New->getMinRequiredArguments() < Old->getMinRequiredArguments()) {
640 CXXSpecialMember NewSM = getSpecialMember(cast<CXXMethodDecl>(New)),
641 OldSM = getSpecialMember(cast<CXXMethodDecl>(Old));
642 if (NewSM != OldSM) {
643 ParmVarDecl *NewParam = New->getParamDecl(New->getMinRequiredArguments());
644 assert(NewParam->hasDefaultArg())(static_cast <bool> (NewParam->hasDefaultArg()) ? void
(0) : __assert_fail ("NewParam->hasDefaultArg()", "clang/lib/Sema/SemaDeclCXX.cpp"
, 644, __extension__ __PRETTY_FUNCTION__))
;
645 Diag(NewParam->getLocation(), diag::err_default_arg_makes_ctor_special)
646 << NewParam->getDefaultArgRange() << NewSM;
647 Diag(Old->getLocation(), diag::note_previous_declaration);
648 }
649 }
650
651 const FunctionDecl *Def;
652 // C++11 [dcl.constexpr]p1: If any declaration of a function or function
653 // template has a constexpr specifier then all its declarations shall
654 // contain the constexpr specifier.
655 if (New->getConstexprKind() != Old->getConstexprKind()) {
656 Diag(New->getLocation(), diag::err_constexpr_redecl_mismatch)
657 << New << static_cast<int>(New->getConstexprKind())
658 << static_cast<int>(Old->getConstexprKind());
659 Diag(Old->getLocation(), diag::note_previous_declaration);
660 Invalid = true;
661 } else if (!Old->getMostRecentDecl()->isInlined() && New->isInlined() &&
662 Old->isDefined(Def) &&
663 // If a friend function is inlined but does not have 'inline'
664 // specifier, it is a definition. Do not report attribute conflict
665 // in this case, redefinition will be diagnosed later.
666 (New->isInlineSpecified() ||
667 New->getFriendObjectKind() == Decl::FOK_None)) {
668 // C++11 [dcl.fcn.spec]p4:
669 // If the definition of a function appears in a translation unit before its
670 // first declaration as inline, the program is ill-formed.
671 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
672 Diag(Def->getLocation(), diag::note_previous_definition);
673 Invalid = true;
674 }
675
676 // C++17 [temp.deduct.guide]p3:
677 // Two deduction guide declarations in the same translation unit
678 // for the same class template shall not have equivalent
679 // parameter-declaration-clauses.
680 if (isa<CXXDeductionGuideDecl>(New) &&
681 !New->isFunctionTemplateSpecialization() && isVisible(Old)) {
682 Diag(New->getLocation(), diag::err_deduction_guide_redeclared);
683 Diag(Old->getLocation(), diag::note_previous_declaration);
684 }
685
686 // C++11 [dcl.fct.default]p4: If a friend declaration specifies a default
687 // argument expression, that declaration shall be a definition and shall be
688 // the only declaration of the function or function template in the
689 // translation unit.
690 if (Old->getFriendObjectKind() == Decl::FOK_Undeclared &&
691 functionDeclHasDefaultArgument(Old)) {
692 Diag(New->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
693 Diag(Old->getLocation(), diag::note_previous_declaration);
694 Invalid = true;
695 }
696
697 // C++11 [temp.friend]p4 (DR329):
698 // When a function is defined in a friend function declaration in a class
699 // template, the function is instantiated when the function is odr-used.
700 // The same restrictions on multiple declarations and definitions that
701 // apply to non-template function declarations and definitions also apply
702 // to these implicit definitions.
703 const FunctionDecl *OldDefinition = nullptr;
704 if (New->isThisDeclarationInstantiatedFromAFriendDefinition() &&
705 Old->isDefined(OldDefinition, true))
706 CheckForFunctionRedefinition(New, OldDefinition);
707
708 return Invalid;
709}
710
711NamedDecl *
712Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
713 MultiTemplateParamsArg TemplateParamLists) {
714 assert(D.isDecompositionDeclarator())(static_cast <bool> (D.isDecompositionDeclarator()) ? void
(0) : __assert_fail ("D.isDecompositionDeclarator()", "clang/lib/Sema/SemaDeclCXX.cpp"
, 714, __extension__ __PRETTY_FUNCTION__))
;
715 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
716
717 // The syntax only allows a decomposition declarator as a simple-declaration,
718 // a for-range-declaration, or a condition in Clang, but we parse it in more
719 // cases than that.
720 if (!D.mayHaveDecompositionDeclarator()) {
721 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
722 << Decomp.getSourceRange();
723 return nullptr;
724 }
725
726 if (!TemplateParamLists.empty()) {
727 // FIXME: There's no rule against this, but there are also no rules that
728 // would actually make it usable, so we reject it for now.
729 Diag(TemplateParamLists.front()->getTemplateLoc(),
730 diag::err_decomp_decl_template);
731 return nullptr;
732 }
733
734 Diag(Decomp.getLSquareLoc(),
735 !getLangOpts().CPlusPlus17
736 ? diag::ext_decomp_decl
737 : D.getContext() == DeclaratorContext::Condition
738 ? diag::ext_decomp_decl_cond
739 : diag::warn_cxx14_compat_decomp_decl)
740 << Decomp.getSourceRange();
741
742 // The semantic context is always just the current context.
743 DeclContext *const DC = CurContext;
744
745 // C++17 [dcl.dcl]/8:
746 // The decl-specifier-seq shall contain only the type-specifier auto
747 // and cv-qualifiers.
748 // C++2a [dcl.dcl]/8:
749 // If decl-specifier-seq contains any decl-specifier other than static,
750 // thread_local, auto, or cv-qualifiers, the program is ill-formed.
751 auto &DS = D.getDeclSpec();
752 {
753 SmallVector<StringRef, 8> BadSpecifiers;
754 SmallVector<SourceLocation, 8> BadSpecifierLocs;
755 SmallVector<StringRef, 8> CPlusPlus20Specifiers;
756 SmallVector<SourceLocation, 8> CPlusPlus20SpecifierLocs;
757 if (auto SCS = DS.getStorageClassSpec()) {
758 if (SCS == DeclSpec::SCS_static) {
759 CPlusPlus20Specifiers.push_back(DeclSpec::getSpecifierName(SCS));
760 CPlusPlus20SpecifierLocs.push_back(DS.getStorageClassSpecLoc());
761 } else {
762 BadSpecifiers.push_back(DeclSpec::getSpecifierName(SCS));
763 BadSpecifierLocs.push_back(DS.getStorageClassSpecLoc());
764 }
765 }
766 if (auto TSCS = DS.getThreadStorageClassSpec()) {
767 CPlusPlus20Specifiers.push_back(DeclSpec::getSpecifierName(TSCS));
768 CPlusPlus20SpecifierLocs.push_back(DS.getThreadStorageClassSpecLoc());
769 }
770 if (DS.hasConstexprSpecifier()) {
771 BadSpecifiers.push_back(
772 DeclSpec::getSpecifierName(DS.getConstexprSpecifier()));
773 BadSpecifierLocs.push_back(DS.getConstexprSpecLoc());
774 }
775 if (DS.isInlineSpecified()) {
776 BadSpecifiers.push_back("inline");
777 BadSpecifierLocs.push_back(DS.getInlineSpecLoc());
778 }
779 if (!BadSpecifiers.empty()) {
780 auto &&Err = Diag(BadSpecifierLocs.front(), diag::err_decomp_decl_spec);
781 Err << (int)BadSpecifiers.size()
782 << llvm::join(BadSpecifiers.begin(), BadSpecifiers.end(), " ");
783 // Don't add FixItHints to remove the specifiers; we do still respect
784 // them when building the underlying variable.
785 for (auto Loc : BadSpecifierLocs)
786 Err << SourceRange(Loc, Loc);
787 } else if (!CPlusPlus20Specifiers.empty()) {
788 auto &&Warn = Diag(CPlusPlus20SpecifierLocs.front(),
789 getLangOpts().CPlusPlus20
790 ? diag::warn_cxx17_compat_decomp_decl_spec
791 : diag::ext_decomp_decl_spec);
792 Warn << (int)CPlusPlus20Specifiers.size()
793 << llvm::join(CPlusPlus20Specifiers.begin(),
794 CPlusPlus20Specifiers.end(), " ");
795 for (auto Loc : CPlusPlus20SpecifierLocs)
796 Warn << SourceRange(Loc, Loc);
797 }
798 // We can't recover from it being declared as a typedef.
799 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
800 return nullptr;
801 }
802
803 // C++2a [dcl.struct.bind]p1:
804 // A cv that includes volatile is deprecated
805 if ((DS.getTypeQualifiers() & DeclSpec::TQ_volatile) &&
806 getLangOpts().CPlusPlus20)
807 Diag(DS.getVolatileSpecLoc(),
808 diag::warn_deprecated_volatile_structured_binding);
809
810 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
811 QualType R = TInfo->getType();
812
813 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
814 UPPC_DeclarationType))
815 D.setInvalidType();
816
817 // The syntax only allows a single ref-qualifier prior to the decomposition
818 // declarator. No other declarator chunks are permitted. Also check the type
819 // specifier here.
820 if (DS.getTypeSpecType() != DeclSpec::TST_auto ||
821 D.hasGroupingParens() || D.getNumTypeObjects() > 1 ||
822 (D.getNumTypeObjects() == 1 &&
823 D.getTypeObject(0).Kind != DeclaratorChunk::Reference)) {
824 Diag(Decomp.getLSquareLoc(),
825 (D.hasGroupingParens() ||
826 (D.getNumTypeObjects() &&
827 D.getTypeObject(0).Kind == DeclaratorChunk::Paren))
828 ? diag::err_decomp_decl_parens
829 : diag::err_decomp_decl_type)
830 << R;
831
832 // In most cases, there's no actual problem with an explicitly-specified
833 // type, but a function type won't work here, and ActOnVariableDeclarator
834 // shouldn't be called for such a type.
835 if (R->isFunctionType())
836 D.setInvalidType();
837 }
838
839 // Build the BindingDecls.
840 SmallVector<BindingDecl*, 8> Bindings;
841
842 // Build the BindingDecls.
843 for (auto &B : D.getDecompositionDeclarator().bindings()) {
844 // Check for name conflicts.
845 DeclarationNameInfo NameInfo(B.Name, B.NameLoc);
846 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
847 ForVisibleRedeclaration);
848 LookupName(Previous, S,
849 /*CreateBuiltins*/DC->getRedeclContext()->isTranslationUnit());
850
851 // It's not permitted to shadow a template parameter name.
852 if (Previous.isSingleResult() &&
853 Previous.getFoundDecl()->isTemplateParameter()) {
854 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
855 Previous.getFoundDecl());
856 Previous.clear();
857 }
858
859 auto *BD = BindingDecl::Create(Context, DC, B.NameLoc, B.Name);
860
861 // Find the shadowed declaration before filtering for scope.
862 NamedDecl *ShadowedDecl = D.getCXXScopeSpec().isEmpty()
863 ? getShadowedDeclaration(BD, Previous)
864 : nullptr;
865
866 bool ConsiderLinkage = DC->isFunctionOrMethod() &&
867 DS.getStorageClassSpec() == DeclSpec::SCS_extern;
868 FilterLookupForScope(Previous, DC, S, ConsiderLinkage,
869 /*AllowInlineNamespace*/false);
870
871 if (!Previous.empty()) {
872 auto *Old = Previous.getRepresentativeDecl();
873 Diag(B.NameLoc, diag::err_redefinition) << B.Name;
874 Diag(Old->getLocation(), diag::note_previous_definition);
875 } else if (ShadowedDecl && !D.isRedeclaration()) {
876 CheckShadow(BD, ShadowedDecl, Previous);
877 }
878 PushOnScopeChains(BD, S, true);
879 Bindings.push_back(BD);
880 ParsingInitForAutoVars.insert(BD);
881 }
882
883 // There are no prior lookup results for the variable itself, because it
884 // is unnamed.
885 DeclarationNameInfo NameInfo((IdentifierInfo *)nullptr,
886 Decomp.getLSquareLoc());
887 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
888 ForVisibleRedeclaration);
889
890 // Build the variable that holds the non-decomposed object.
891 bool AddToScope = true;
892 NamedDecl *New =
893 ActOnVariableDeclarator(S, D, DC, TInfo, Previous,
894 MultiTemplateParamsArg(), AddToScope, Bindings);
895 if (AddToScope) {
896 S->AddDecl(New);
897 CurContext->addHiddenDecl(New);
898 }
899
900 if (isInOpenMPDeclareTargetContext())
901 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
902
903 return New;
904}
905
906static bool checkSimpleDecomposition(
907 Sema &S, ArrayRef<BindingDecl *> Bindings, ValueDecl *Src,
908 QualType DecompType, const llvm::APSInt &NumElems, QualType ElemType,
909 llvm::function_ref<ExprResult(SourceLocation, Expr *, unsigned)> GetInit) {
910 if ((int64_t)Bindings.size() != NumElems) {
911 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
912 << DecompType << (unsigned)Bindings.size()
913 << (unsigned)NumElems.getLimitedValue(UINT_MAX(2147483647 *2U +1U))
914 << toString(NumElems, 10) << (NumElems < Bindings.size());
915 return true;
916 }
917
918 unsigned I = 0;
919 for (auto *B : Bindings) {
920 SourceLocation Loc = B->getLocation();
921 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
922 if (E.isInvalid())
923 return true;
924 E = GetInit(Loc, E.get(), I++);
925 if (E.isInvalid())
926 return true;
927 B->setBinding(ElemType, E.get());
928 }
929
930 return false;
931}
932
933static bool checkArrayLikeDecomposition(Sema &S,
934 ArrayRef<BindingDecl *> Bindings,
935 ValueDecl *Src, QualType DecompType,
936 const llvm::APSInt &NumElems,
937 QualType ElemType) {
938 return checkSimpleDecomposition(
939 S, Bindings, Src, DecompType, NumElems, ElemType,
940 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
941 ExprResult E = S.ActOnIntegerConstant(Loc, I);
942 if (E.isInvalid())
943 return ExprError();
944 return S.CreateBuiltinArraySubscriptExpr(Base, Loc, E.get(), Loc);
945 });
946}
947
948static bool checkArrayDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
949 ValueDecl *Src, QualType DecompType,
950 const ConstantArrayType *CAT) {
951 return checkArrayLikeDecomposition(S, Bindings, Src, DecompType,
952 llvm::APSInt(CAT->getSize()),
953 CAT->getElementType());
954}
955
956static bool checkVectorDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
957 ValueDecl *Src, QualType DecompType,
958 const VectorType *VT) {
959 return checkArrayLikeDecomposition(
960 S, Bindings, Src, DecompType, llvm::APSInt::get(VT->getNumElements()),
961 S.Context.getQualifiedType(VT->getElementType(),
962 DecompType.getQualifiers()));
963}
964
965static bool checkComplexDecomposition(Sema &S,
966 ArrayRef<BindingDecl *> Bindings,
967 ValueDecl *Src, QualType DecompType,
968 const ComplexType *CT) {
969 return checkSimpleDecomposition(
970 S, Bindings, Src, DecompType, llvm::APSInt::get(2),
971 S.Context.getQualifiedType(CT->getElementType(),
972 DecompType.getQualifiers()),
973 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
974 return S.CreateBuiltinUnaryOp(Loc, I ? UO_Imag : UO_Real, Base);
975 });
976}
977
978static std::string printTemplateArgs(const PrintingPolicy &PrintingPolicy,
979 TemplateArgumentListInfo &Args,
980 const TemplateParameterList *Params) {
981 SmallString<128> SS;
982 llvm::raw_svector_ostream OS(SS);
983 bool First = true;
984 unsigned I = 0;
985 for (auto &Arg : Args.arguments()) {
986 if (!First)
987 OS << ", ";
988 Arg.getArgument().print(PrintingPolicy, OS,
989 TemplateParameterList::shouldIncludeTypeForArgument(
990 PrintingPolicy, Params, I));
991 First = false;
992 I++;
993 }
994 return std::string(OS.str());
995}
996
997static bool lookupStdTypeTraitMember(Sema &S, LookupResult &TraitMemberLookup,
998 SourceLocation Loc, StringRef Trait,
999 TemplateArgumentListInfo &Args,
1000 unsigned DiagID) {
1001 auto DiagnoseMissing = [&] {
1002 if (DiagID)
1003 S.Diag(Loc, DiagID) << printTemplateArgs(S.Context.getPrintingPolicy(),
1004 Args, /*Params*/ nullptr);
1005 return true;
1006 };
1007
1008 // FIXME: Factor out duplication with lookupPromiseType in SemaCoroutine.
1009 NamespaceDecl *Std = S.getStdNamespace();
1010 if (!Std)
1011 return DiagnoseMissing();
1012
1013 // Look up the trait itself, within namespace std. We can diagnose various
1014 // problems with this lookup even if we've been asked to not diagnose a
1015 // missing specialization, because this can only fail if the user has been
1016 // declaring their own names in namespace std or we don't support the
1017 // standard library implementation in use.
1018 LookupResult Result(S, &S.PP.getIdentifierTable().get(Trait),
1019 Loc, Sema::LookupOrdinaryName);
1020 if (!S.LookupQualifiedName(Result, Std))
1021 return DiagnoseMissing();
1022 if (Result.isAmbiguous())
1023 return true;
1024
1025 ClassTemplateDecl *TraitTD = Result.getAsSingle<ClassTemplateDecl>();
1026 if (!TraitTD) {
1027 Result.suppressDiagnostics();
1028 NamedDecl *Found = *Result.begin();
1029 S.Diag(Loc, diag::err_std_type_trait_not_class_template) << Trait;
1030 S.Diag(Found->getLocation(), diag::note_declared_at);
1031 return true;
1032 }
1033
1034 // Build the template-id.
1035 QualType TraitTy = S.CheckTemplateIdType(TemplateName(TraitTD), Loc, Args);
1036 if (TraitTy.isNull())
1037 return true;
1038 if (!S.isCompleteType(Loc, TraitTy)) {
1039 if (DiagID)
1040 S.RequireCompleteType(
1041 Loc, TraitTy, DiagID,
1042 printTemplateArgs(S.Context.getPrintingPolicy(), Args,
1043 TraitTD->getTemplateParameters()));
1044 return true;
1045 }
1046
1047 CXXRecordDecl *RD = TraitTy->getAsCXXRecordDecl();
1048 assert(RD && "specialization of class template is not a class?")(static_cast <bool> (RD && "specialization of class template is not a class?"
) ? void (0) : __assert_fail ("RD && \"specialization of class template is not a class?\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 1048, __extension__ __PRETTY_FUNCTION__
))
;
1049
1050 // Look up the member of the trait type.
1051 S.LookupQualifiedName(TraitMemberLookup, RD);
1052 return TraitMemberLookup.isAmbiguous();
1053}
1054
1055static TemplateArgumentLoc
1056getTrivialIntegralTemplateArgument(Sema &S, SourceLocation Loc, QualType T,
1057 uint64_t I) {
1058 TemplateArgument Arg(S.Context, S.Context.MakeIntValue(I, T), T);
1059 return S.getTrivialTemplateArgumentLoc(Arg, T, Loc);
1060}
1061
1062static TemplateArgumentLoc
1063getTrivialTypeTemplateArgument(Sema &S, SourceLocation Loc, QualType T) {
1064 return S.getTrivialTemplateArgumentLoc(TemplateArgument(T), QualType(), Loc);
1065}
1066
1067namespace { enum class IsTupleLike { TupleLike, NotTupleLike, Error }; }
1068
1069static IsTupleLike isTupleLike(Sema &S, SourceLocation Loc, QualType T,
1070 llvm::APSInt &Size) {
1071 EnterExpressionEvaluationContext ContextRAII(
1072 S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
1073
1074 DeclarationName Value = S.PP.getIdentifierInfo("value");
1075 LookupResult R(S, Value, Loc, Sema::LookupOrdinaryName);
1076
1077 // Form template argument list for tuple_size<T>.
1078 TemplateArgumentListInfo Args(Loc, Loc);
1079 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
1080
1081 // If there's no tuple_size specialization or the lookup of 'value' is empty,
1082 // it's not tuple-like.
1083 if (lookupStdTypeTraitMember(S, R, Loc, "tuple_size", Args, /*DiagID*/ 0) ||
1084 R.empty())
1085 return IsTupleLike::NotTupleLike;
1086
1087 // If we get this far, we've committed to the tuple interpretation, but
1088 // we can still fail if there actually isn't a usable ::value.
1089
1090 struct ICEDiagnoser : Sema::VerifyICEDiagnoser {
1091 LookupResult &R;
1092 TemplateArgumentListInfo &Args;
1093 ICEDiagnoser(LookupResult &R, TemplateArgumentListInfo &Args)
1094 : R(R), Args(Args) {}
1095 Sema::SemaDiagnosticBuilder diagnoseNotICE(Sema &S,
1096 SourceLocation Loc) override {
1097 return S.Diag(Loc, diag::err_decomp_decl_std_tuple_size_not_constant)
1098 << printTemplateArgs(S.Context.getPrintingPolicy(), Args,
1099 /*Params*/ nullptr);
1100 }
1101 } Diagnoser(R, Args);
1102
1103 ExprResult E =
1104 S.BuildDeclarationNameExpr(CXXScopeSpec(), R, /*NeedsADL*/false);
1105 if (E.isInvalid())
1106 return IsTupleLike::Error;
1107
1108 E = S.VerifyIntegerConstantExpression(E.get(), &Size, Diagnoser);
1109 if (E.isInvalid())
1110 return IsTupleLike::Error;
1111
1112 return IsTupleLike::TupleLike;
1113}
1114
1115/// \return std::tuple_element<I, T>::type.
1116static QualType getTupleLikeElementType(Sema &S, SourceLocation Loc,
1117 unsigned I, QualType T) {
1118 // Form template argument list for tuple_element<I, T>.
1119 TemplateArgumentListInfo Args(Loc, Loc);
1120 Args.addArgument(
1121 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1122 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
1123
1124 DeclarationName TypeDN = S.PP.getIdentifierInfo("type");
1125 LookupResult R(S, TypeDN, Loc, Sema::LookupOrdinaryName);
1126 if (lookupStdTypeTraitMember(
1127 S, R, Loc, "tuple_element", Args,
1128 diag::err_decomp_decl_std_tuple_element_not_specialized))
1129 return QualType();
1130
1131 auto *TD = R.getAsSingle<TypeDecl>();
1132 if (!TD) {
1133 R.suppressDiagnostics();
1134 S.Diag(Loc, diag::err_decomp_decl_std_tuple_element_not_specialized)
1135 << printTemplateArgs(S.Context.getPrintingPolicy(), Args,
1136 /*Params*/ nullptr);
1137 if (!R.empty())
1138 S.Diag(R.getRepresentativeDecl()->getLocation(), diag::note_declared_at);
1139 return QualType();
1140 }
1141
1142 return S.Context.getTypeDeclType(TD);
1143}
1144
1145namespace {
1146struct InitializingBinding {
1147 Sema &S;
1148 InitializingBinding(Sema &S, BindingDecl *BD) : S(S) {
1149 Sema::CodeSynthesisContext Ctx;
1150 Ctx.Kind = Sema::CodeSynthesisContext::InitializingStructuredBinding;
1151 Ctx.PointOfInstantiation = BD->getLocation();
1152 Ctx.Entity = BD;
1153 S.pushCodeSynthesisContext(Ctx);
1154 }
1155 ~InitializingBinding() {
1156 S.popCodeSynthesisContext();
1157 }
1158};
1159}
1160
1161static bool checkTupleLikeDecomposition(Sema &S,
1162 ArrayRef<BindingDecl *> Bindings,
1163 VarDecl *Src, QualType DecompType,
1164 const llvm::APSInt &TupleSize) {
1165 if ((int64_t)Bindings.size() != TupleSize) {
1166 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1167 << DecompType << (unsigned)Bindings.size()
1168 << (unsigned)TupleSize.getLimitedValue(UINT_MAX(2147483647 *2U +1U))
1169 << toString(TupleSize, 10) << (TupleSize < Bindings.size());
1170 return true;
1171 }
1172
1173 if (Bindings.empty())
1174 return false;
1175
1176 DeclarationName GetDN = S.PP.getIdentifierInfo("get");
1177
1178 // [dcl.decomp]p3:
1179 // The unqualified-id get is looked up in the scope of E by class member
1180 // access lookup ...
1181 LookupResult MemberGet(S, GetDN, Src->getLocation(), Sema::LookupMemberName);
1182 bool UseMemberGet = false;
1183 if (S.isCompleteType(Src->getLocation(), DecompType)) {
1184 if (auto *RD = DecompType->getAsCXXRecordDecl())
1185 S.LookupQualifiedName(MemberGet, RD);
1186 if (MemberGet.isAmbiguous())
1187 return true;
1188 // ... and if that finds at least one declaration that is a function
1189 // template whose first template parameter is a non-type parameter ...
1190 for (NamedDecl *D : MemberGet) {
1191 if (FunctionTemplateDecl *FTD =
1192 dyn_cast<FunctionTemplateDecl>(D->getUnderlyingDecl())) {
1193 TemplateParameterList *TPL = FTD->getTemplateParameters();
1194 if (TPL->size() != 0 &&
1195 isa<NonTypeTemplateParmDecl>(TPL->getParam(0))) {
1196 // ... the initializer is e.get<i>().
1197 UseMemberGet = true;
1198 break;
1199 }
1200 }
1201 }
1202 }
1203
1204 unsigned I = 0;
1205 for (auto *B : Bindings) {
1206 InitializingBinding InitContext(S, B);
1207 SourceLocation Loc = B->getLocation();
1208
1209 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1210 if (E.isInvalid())
1211 return true;
1212
1213 // e is an lvalue if the type of the entity is an lvalue reference and
1214 // an xvalue otherwise
1215 if (!Src->getType()->isLValueReferenceType())
1216 E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), CK_NoOp,
1217 E.get(), nullptr, VK_XValue,
1218 FPOptionsOverride());
1219
1220 TemplateArgumentListInfo Args(Loc, Loc);
1221 Args.addArgument(
1222 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1223
1224 if (UseMemberGet) {
1225 // if [lookup of member get] finds at least one declaration, the
1226 // initializer is e.get<i-1>().
1227 E = S.BuildMemberReferenceExpr(E.get(), DecompType, Loc, false,
1228 CXXScopeSpec(), SourceLocation(), nullptr,
1229 MemberGet, &Args, nullptr);
1230 if (E.isInvalid())
1231 return true;
1232
1233 E = S.BuildCallExpr(nullptr, E.get(), Loc, None, Loc);
1234 } else {
1235 // Otherwise, the initializer is get<i-1>(e), where get is looked up
1236 // in the associated namespaces.
1237 Expr *Get = UnresolvedLookupExpr::Create(
1238 S.Context, nullptr, NestedNameSpecifierLoc(), SourceLocation(),
1239 DeclarationNameInfo(GetDN, Loc), /*RequiresADL*/true, &Args,
1240 UnresolvedSetIterator(), UnresolvedSetIterator());
1241
1242 Expr *Arg = E.get();
1243 E = S.BuildCallExpr(nullptr, Get, Loc, Arg, Loc);
1244 }
1245 if (E.isInvalid())
1246 return true;
1247 Expr *Init = E.get();
1248
1249 // Given the type T designated by std::tuple_element<i - 1, E>::type,
1250 QualType T = getTupleLikeElementType(S, Loc, I, DecompType);
1251 if (T.isNull())
1252 return true;
1253
1254 // each vi is a variable of type "reference to T" initialized with the
1255 // initializer, where the reference is an lvalue reference if the
1256 // initializer is an lvalue and an rvalue reference otherwise
1257 QualType RefType =
1258 S.BuildReferenceType(T, E.get()->isLValue(), Loc, B->getDeclName());
1259 if (RefType.isNull())
1260 return true;
1261 auto *RefVD = VarDecl::Create(
1262 S.Context, Src->getDeclContext(), Loc, Loc,
1263 B->getDeclName().getAsIdentifierInfo(), RefType,
1264 S.Context.getTrivialTypeSourceInfo(T, Loc), Src->getStorageClass());
1265 RefVD->setLexicalDeclContext(Src->getLexicalDeclContext());
1266 RefVD->setTSCSpec(Src->getTSCSpec());
1267 RefVD->setImplicit();
1268 if (Src->isInlineSpecified())
1269 RefVD->setInlineSpecified();
1270 RefVD->getLexicalDeclContext()->addHiddenDecl(RefVD);
1271
1272 InitializedEntity Entity = InitializedEntity::InitializeBinding(RefVD);
1273 InitializationKind Kind = InitializationKind::CreateCopy(Loc, Loc);
1274 InitializationSequence Seq(S, Entity, Kind, Init);
1275 E = Seq.Perform(S, Entity, Kind, Init);
1276 if (E.isInvalid())
1277 return true;
1278 E = S.ActOnFinishFullExpr(E.get(), Loc, /*DiscardedValue*/ false);
1279 if (E.isInvalid())
1280 return true;
1281 RefVD->setInit(E.get());
1282 S.CheckCompleteVariableDeclaration(RefVD);
1283
1284 E = S.BuildDeclarationNameExpr(CXXScopeSpec(),
1285 DeclarationNameInfo(B->getDeclName(), Loc),
1286 RefVD);
1287 if (E.isInvalid())
1288 return true;
1289
1290 B->setBinding(T, E.get());
1291 I++;
1292 }
1293
1294 return false;
1295}
1296
1297/// Find the base class to decompose in a built-in decomposition of a class type.
1298/// This base class search is, unfortunately, not quite like any other that we
1299/// perform anywhere else in C++.
1300static DeclAccessPair findDecomposableBaseClass(Sema &S, SourceLocation Loc,
1301 const CXXRecordDecl *RD,
1302 CXXCastPath &BasePath) {
1303 auto BaseHasFields = [](const CXXBaseSpecifier *Specifier,
1304 CXXBasePath &Path) {
1305 return Specifier->getType()->getAsCXXRecordDecl()->hasDirectFields();
1306 };
1307
1308 const CXXRecordDecl *ClassWithFields = nullptr;
1309 AccessSpecifier AS = AS_public;
1310 if (RD->hasDirectFields())
16
Assuming the condition is false
17
Taking false branch
1311 // [dcl.decomp]p4:
1312 // Otherwise, all of E's non-static data members shall be public direct
1313 // members of E ...
1314 ClassWithFields = RD;
1315 else {
1316 // ... or of ...
1317 CXXBasePaths Paths;
1318 Paths.setOrigin(const_cast<CXXRecordDecl*>(RD));
1319 if (!RD->lookupInBases(BaseHasFields, Paths)) {
18
Assuming the condition is false
19
Taking false branch
1320 // If no classes have fields, just decompose RD itself. (This will work
1321 // if and only if zero bindings were provided.)
1322 return DeclAccessPair::make(const_cast<CXXRecordDecl*>(RD), AS_public);
1323 }
1324
1325 CXXBasePath *BestPath = nullptr;
20
'BestPath' initialized to a null pointer value
1326 for (auto &P : Paths) {
1327 if (!BestPath)
1328 BestPath = &P;
1329 else if (!S.Context.hasSameType(P.back().Base->getType(),
1330 BestPath->back().Base->getType())) {
1331 // ... the same ...
1332 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1333 << false << RD << BestPath->back().Base->getType()
1334 << P.back().Base->getType();
1335 return DeclAccessPair();
1336 } else if (P.Access < BestPath->Access) {
1337 BestPath = &P;
1338 }
1339 }
1340
1341 // ... unambiguous ...
1342 QualType BaseType = BestPath->back().Base->getType();
21
Called C++ object pointer is null
1343 if (Paths.isAmbiguous(S.Context.getCanonicalType(BaseType))) {
1344 S.Diag(Loc, diag::err_decomp_decl_ambiguous_base)
1345 << RD << BaseType << S.getAmbiguousPathsDisplayString(Paths);
1346 return DeclAccessPair();
1347 }
1348
1349 // ... [accessible, implied by other rules] base class of E.
1350 S.CheckBaseClassAccess(Loc, BaseType, S.Context.getRecordType(RD),
1351 *BestPath, diag::err_decomp_decl_inaccessible_base);
1352 AS = BestPath->Access;
1353
1354 ClassWithFields = BaseType->getAsCXXRecordDecl();
1355 S.BuildBasePathArray(Paths, BasePath);
1356 }
1357
1358 // The above search did not check whether the selected class itself has base
1359 // classes with fields, so check that now.
1360 CXXBasePaths Paths;
1361 if (ClassWithFields->lookupInBases(BaseHasFields, Paths)) {
1362 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1363 << (ClassWithFields == RD) << RD << ClassWithFields
1364 << Paths.front().back().Base->getType();
1365 return DeclAccessPair();
1366 }
1367
1368 return DeclAccessPair::make(const_cast<CXXRecordDecl*>(ClassWithFields), AS);
1369}
1370
1371static bool checkMemberDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
1372 ValueDecl *Src, QualType DecompType,
1373 const CXXRecordDecl *OrigRD) {
1374 if (S.RequireCompleteType(Src->getLocation(), DecompType,
13
Assuming the condition is false
14
Taking false branch
1375 diag::err_incomplete_type))
1376 return true;
1377
1378 CXXCastPath BasePath;
1379 DeclAccessPair BasePair =
1380 findDecomposableBaseClass(S, Src->getLocation(), OrigRD, BasePath);
15
Calling 'findDecomposableBaseClass'
1381 const CXXRecordDecl *RD = cast_or_null<CXXRecordDecl>(BasePair.getDecl());
1382 if (!RD)
1383 return true;
1384 QualType BaseType = S.Context.getQualifiedType(S.Context.getRecordType(RD),
1385 DecompType.getQualifiers());
1386
1387 auto DiagnoseBadNumberOfBindings = [&]() -> bool {
1388 unsigned NumFields = llvm::count_if(
1389 RD->fields(), [](FieldDecl *FD) { return !FD->isUnnamedBitfield(); });
1390 assert(Bindings.size() != NumFields)(static_cast <bool> (Bindings.size() != NumFields) ? void
(0) : __assert_fail ("Bindings.size() != NumFields", "clang/lib/Sema/SemaDeclCXX.cpp"
, 1390, __extension__ __PRETTY_FUNCTION__))
;
1391 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1392 << DecompType << (unsigned)Bindings.size() << NumFields << NumFields
1393 << (NumFields < Bindings.size());
1394 return true;
1395 };
1396
1397 // all of E's non-static data members shall be [...] well-formed
1398 // when named as e.name in the context of the structured binding,
1399 // E shall not have an anonymous union member, ...
1400 unsigned I = 0;
1401 for (auto *FD : RD->fields()) {
1402 if (FD->isUnnamedBitfield())
1403 continue;
1404
1405 // All the non-static data members are required to be nameable, so they
1406 // must all have names.
1407 if (!FD->getDeclName()) {
1408 if (RD->isLambda()) {
1409 S.Diag(Src->getLocation(), diag::err_decomp_decl_lambda);
1410 S.Diag(RD->getLocation(), diag::note_lambda_decl);
1411 return true;
1412 }
1413
1414 if (FD->isAnonymousStructOrUnion()) {
1415 S.Diag(Src->getLocation(), diag::err_decomp_decl_anon_union_member)
1416 << DecompType << FD->getType()->isUnionType();
1417 S.Diag(FD->getLocation(), diag::note_declared_at);
1418 return true;
1419 }
1420
1421 // FIXME: Are there any other ways we could have an anonymous member?
1422 }
1423
1424 // We have a real field to bind.
1425 if (I >= Bindings.size())
1426 return DiagnoseBadNumberOfBindings();
1427 auto *B = Bindings[I++];
1428 SourceLocation Loc = B->getLocation();
1429
1430 // The field must be accessible in the context of the structured binding.
1431 // We already checked that the base class is accessible.
1432 // FIXME: Add 'const' to AccessedEntity's classes so we can remove the
1433 // const_cast here.
1434 S.CheckStructuredBindingMemberAccess(
1435 Loc, const_cast<CXXRecordDecl *>(OrigRD),
1436 DeclAccessPair::make(FD, CXXRecordDecl::MergeAccess(
1437 BasePair.getAccess(), FD->getAccess())));
1438
1439 // Initialize the binding to Src.FD.
1440 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1441 if (E.isInvalid())
1442 return true;
1443 E = S.ImpCastExprToType(E.get(), BaseType, CK_UncheckedDerivedToBase,
1444 VK_LValue, &BasePath);
1445 if (E.isInvalid())
1446 return true;
1447 E = S.BuildFieldReferenceExpr(E.get(), /*IsArrow*/ false, Loc,
1448 CXXScopeSpec(), FD,
1449 DeclAccessPair::make(FD, FD->getAccess()),
1450 DeclarationNameInfo(FD->getDeclName(), Loc));
1451 if (E.isInvalid())
1452 return true;
1453
1454 // If the type of the member is T, the referenced type is cv T, where cv is
1455 // the cv-qualification of the decomposition expression.
1456 //
1457 // FIXME: We resolve a defect here: if the field is mutable, we do not add
1458 // 'const' to the type of the field.
1459 Qualifiers Q = DecompType.getQualifiers();
1460 if (FD->isMutable())
1461 Q.removeConst();
1462 B->setBinding(S.BuildQualifiedType(FD->getType(), Loc, Q), E.get());
1463 }
1464
1465 if (I != Bindings.size())
1466 return DiagnoseBadNumberOfBindings();
1467
1468 return false;
1469}
1470
1471void Sema::CheckCompleteDecompositionDeclaration(DecompositionDecl *DD) {
1472 QualType DecompType = DD->getType();
1473
1474 // If the type of the decomposition is dependent, then so is the type of
1475 // each binding.
1476 if (DecompType->isDependentType()) {
1
Assuming the condition is false
2
Taking false branch
1477 for (auto *B : DD->bindings())
1478 B->setType(Context.DependentTy);
1479 return;
1480 }
1481
1482 DecompType = DecompType.getNonReferenceType();
1483 ArrayRef<BindingDecl*> Bindings = DD->bindings();
1484
1485 // C++1z [dcl.decomp]/2:
1486 // If E is an array type [...]
1487 // As an extension, we also support decomposition of built-in complex and
1488 // vector types.
1489 if (auto *CAT
2.1
'CAT' is null
= Context.getAsConstantArrayType(DecompType)) {
3
Taking false branch
1490 if (checkArrayDecomposition(*this, Bindings, DD, DecompType, CAT))
1491 DD->setInvalidDecl();
1492 return;
1493 }
1494 if (auto *VT
4.1
'VT' is null
= DecompType->getAs<VectorType>()) {
4
Assuming the object is not a 'const class clang::VectorType *'
5
Taking false branch
1495 if (checkVectorDecomposition(*this, Bindings, DD, DecompType, VT))
1496 DD->setInvalidDecl();
1497 return;
1498 }
1499 if (auto *CT
6.1
'CT' is null
= DecompType->getAs<ComplexType>()) {
6
Assuming the object is not a 'const class clang::ComplexType *'
7
Taking false branch
1500 if (checkComplexDecomposition(*this, Bindings, DD, DecompType, CT))
1501 DD->setInvalidDecl();
1502 return;
1503 }
1504
1505 // C++1z [dcl.decomp]/3:
1506 // if the expression std::tuple_size<E>::value is a well-formed integral
1507 // constant expression, [...]
1508 llvm::APSInt TupleSize(32);
1509 switch (isTupleLike(*this, DD->getLocation(), DecompType, TupleSize)) {
8
Control jumps to 'case NotTupleLike:' at line 1519
1510 case IsTupleLike::Error:
1511 DD->setInvalidDecl();
1512 return;
1513
1514 case IsTupleLike::TupleLike:
1515 if (checkTupleLikeDecomposition(*this, Bindings, DD, DecompType, TupleSize))
1516 DD->setInvalidDecl();
1517 return;
1518
1519 case IsTupleLike::NotTupleLike:
1520 break;
9
Execution continues on line 1525
1521 }
1522
1523 // C++1z [dcl.dcl]/8:
1524 // [E shall be of array or non-union class type]
1525 CXXRecordDecl *RD = DecompType->getAsCXXRecordDecl();
1526 if (!RD || RD->isUnion()) {
10
Assuming 'RD' is non-null
11
Taking false branch
1527 Diag(DD->getLocation(), diag::err_decomp_decl_unbindable_type)
1528 << DD << !RD << DecompType;
1529 DD->setInvalidDecl();
1530 return;
1531 }
1532
1533 // C++1z [dcl.decomp]/4:
1534 // all of E's non-static data members shall be [...] direct members of
1535 // E or of the same unambiguous public base class of E, ...
1536 if (checkMemberDecomposition(*this, Bindings, DD, DecompType, RD))
12
Calling 'checkMemberDecomposition'
1537 DD->setInvalidDecl();
1538}
1539
1540/// Merge the exception specifications of two variable declarations.
1541///
1542/// This is called when there's a redeclaration of a VarDecl. The function
1543/// checks if the redeclaration might have an exception specification and
1544/// validates compatibility and merges the specs if necessary.
1545void Sema::MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old) {
1546 // Shortcut if exceptions are disabled.
1547 if (!getLangOpts().CXXExceptions)
1548 return;
1549
1550 assert(Context.hasSameType(New->getType(), Old->getType()) &&(static_cast <bool> (Context.hasSameType(New->getType
(), Old->getType()) && "Should only be called if types are otherwise the same."
) ? void (0) : __assert_fail ("Context.hasSameType(New->getType(), Old->getType()) && \"Should only be called if types are otherwise the same.\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 1551, __extension__ __PRETTY_FUNCTION__
))
1551 "Should only be called if types are otherwise the same.")(static_cast <bool> (Context.hasSameType(New->getType
(), Old->getType()) && "Should only be called if types are otherwise the same."
) ? void (0) : __assert_fail ("Context.hasSameType(New->getType(), Old->getType()) && \"Should only be called if types are otherwise the same.\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 1551, __extension__ __PRETTY_FUNCTION__
))
;
1552
1553 QualType NewType = New->getType();
1554 QualType OldType = Old->getType();
1555
1556 // We're only interested in pointers and references to functions, as well
1557 // as pointers to member functions.
1558 if (const ReferenceType *R = NewType->getAs<ReferenceType>()) {
1559 NewType = R->getPointeeType();
1560 OldType = OldType->castAs<ReferenceType>()->getPointeeType();
1561 } else if (const PointerType *P = NewType->getAs<PointerType>()) {
1562 NewType = P->getPointeeType();
1563 OldType = OldType->castAs<PointerType>()->getPointeeType();
1564 } else if (const MemberPointerType *M = NewType->getAs<MemberPointerType>()) {
1565 NewType = M->getPointeeType();
1566 OldType = OldType->castAs<MemberPointerType>()->getPointeeType();
1567 }
1568
1569 if (!NewType->isFunctionProtoType())
1570 return;
1571
1572 // There's lots of special cases for functions. For function pointers, system
1573 // libraries are hopefully not as broken so that we don't need these
1574 // workarounds.
1575 if (CheckEquivalentExceptionSpec(
1576 OldType->getAs<FunctionProtoType>(), Old->getLocation(),
1577 NewType->getAs<FunctionProtoType>(), New->getLocation())) {
1578 New->setInvalidDecl();
1579 }
1580}
1581
1582/// CheckCXXDefaultArguments - Verify that the default arguments for a
1583/// function declaration are well-formed according to C++
1584/// [dcl.fct.default].
1585void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) {
1586 unsigned NumParams = FD->getNumParams();
1587 unsigned ParamIdx = 0;
1588
1589 // This checking doesn't make sense for explicit specializations; their
1590 // default arguments are determined by the declaration we're specializing,
1591 // not by FD.
1592 if (FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
1593 return;
1594 if (auto *FTD = FD->getDescribedFunctionTemplate())
1595 if (FTD->isMemberSpecialization())
1596 return;
1597
1598 // Find first parameter with a default argument
1599 for (; ParamIdx < NumParams; ++ParamIdx) {
1600 ParmVarDecl *Param = FD->getParamDecl(ParamIdx);
1601 if (Param->hasDefaultArg())
1602 break;
1603 }
1604
1605 // C++20 [dcl.fct.default]p4:
1606 // In a given function declaration, each parameter subsequent to a parameter
1607 // with a default argument shall have a default argument supplied in this or
1608 // a previous declaration, unless the parameter was expanded from a
1609 // parameter pack, or shall be a function parameter pack.
1610 for (; ParamIdx < NumParams; ++ParamIdx) {
1611 ParmVarDecl *Param = FD->getParamDecl(ParamIdx);
1612 if (!Param->hasDefaultArg() && !Param->isParameterPack() &&
1613 !(CurrentInstantiationScope &&
1614 CurrentInstantiationScope->isLocalPackExpansion(Param))) {
1615 if (Param->isInvalidDecl())
1616 /* We already complained about this parameter. */;
1617 else if (Param->getIdentifier())
1618 Diag(Param->getLocation(),
1619 diag::err_param_default_argument_missing_name)
1620 << Param->getIdentifier();
1621 else
1622 Diag(Param->getLocation(),
1623 diag::err_param_default_argument_missing);
1624 }
1625 }
1626}
1627
1628/// Check that the given type is a literal type. Issue a diagnostic if not,
1629/// if Kind is Diagnose.
1630/// \return \c true if a problem has been found (and optionally diagnosed).
1631template <typename... Ts>
1632static bool CheckLiteralType(Sema &SemaRef, Sema::CheckConstexprKind Kind,
1633 SourceLocation Loc, QualType T, unsigned DiagID,
1634 Ts &&...DiagArgs) {
1635 if (T->isDependentType())
1636 return false;
1637
1638 switch (Kind) {
1639 case Sema::CheckConstexprKind::Diagnose:
1640 return SemaRef.RequireLiteralType(Loc, T, DiagID,
1641 std::forward<Ts>(DiagArgs)...);
1642
1643 case Sema::CheckConstexprKind::CheckValid:
1644 return !T->isLiteralType(SemaRef.Context);
1645 }
1646
1647 llvm_unreachable("unknown CheckConstexprKind")::llvm::llvm_unreachable_internal("unknown CheckConstexprKind"
, "clang/lib/Sema/SemaDeclCXX.cpp", 1647)
;
1648}
1649
1650/// Determine whether a destructor cannot be constexpr due to
1651static bool CheckConstexprDestructorSubobjects(Sema &SemaRef,
1652 const CXXDestructorDecl *DD,
1653 Sema::CheckConstexprKind Kind) {
1654 auto Check = [&](SourceLocation Loc, QualType T, const FieldDecl *FD) {
1655 const CXXRecordDecl *RD =
1656 T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
1657 if (!RD || RD->hasConstexprDestructor())
1658 return true;
1659
1660 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1661 SemaRef.Diag(DD->getLocation(), diag::err_constexpr_dtor_subobject)
1662 << static_cast<int>(DD->getConstexprKind()) << !FD
1663 << (FD ? FD->getDeclName() : DeclarationName()) << T;
1664 SemaRef.Diag(Loc, diag::note_constexpr_dtor_subobject)
1665 << !FD << (FD ? FD->getDeclName() : DeclarationName()) << T;
1666 }
1667 return false;
1668 };
1669
1670 const CXXRecordDecl *RD = DD->getParent();
1671 for (const CXXBaseSpecifier &B : RD->bases())
1672 if (!Check(B.getBaseTypeLoc(), B.getType(), nullptr))
1673 return false;
1674 for (const FieldDecl *FD : RD->fields())
1675 if (!Check(FD->getLocation(), FD->getType(), FD))
1676 return false;
1677 return true;
1678}
1679
1680/// Check whether a function's parameter types are all literal types. If so,
1681/// return true. If not, produce a suitable diagnostic and return false.
1682static bool CheckConstexprParameterTypes(Sema &SemaRef,
1683 const FunctionDecl *FD,
1684 Sema::CheckConstexprKind Kind) {
1685 unsigned ArgIndex = 0;
1686 const auto *FT = FD->getType()->castAs<FunctionProtoType>();
1687 for (FunctionProtoType::param_type_iterator i = FT->param_type_begin(),
1688 e = FT->param_type_end();
1689 i != e; ++i, ++ArgIndex) {
1690 const ParmVarDecl *PD = FD->getParamDecl(ArgIndex);
1691 SourceLocation ParamLoc = PD->getLocation();
1692 if (CheckLiteralType(SemaRef, Kind, ParamLoc, *i,
1693 diag::err_constexpr_non_literal_param, ArgIndex + 1,
1694 PD->getSourceRange(), isa<CXXConstructorDecl>(FD),
1695 FD->isConsteval()))
1696 return false;
1697 }
1698 return true;
1699}
1700
1701/// Check whether a function's return type is a literal type. If so, return
1702/// true. If not, produce a suitable diagnostic and return false.
1703static bool CheckConstexprReturnType(Sema &SemaRef, const FunctionDecl *FD,
1704 Sema::CheckConstexprKind Kind) {
1705 if (CheckLiteralType(SemaRef, Kind, FD->getLocation(), FD->getReturnType(),
1706 diag::err_constexpr_non_literal_return,
1707 FD->isConsteval()))
1708 return false;
1709 return true;
1710}
1711
1712/// Get diagnostic %select index for tag kind for
1713/// record diagnostic message.
1714/// WARNING: Indexes apply to particular diagnostics only!
1715///
1716/// \returns diagnostic %select index.
1717static unsigned getRecordDiagFromTagKind(TagTypeKind Tag) {
1718 switch (Tag) {
1719 case TTK_Struct: return 0;
1720 case TTK_Interface: return 1;
1721 case TTK_Class: return 2;
1722 default: llvm_unreachable("Invalid tag kind for record diagnostic!")::llvm::llvm_unreachable_internal("Invalid tag kind for record diagnostic!"
, "clang/lib/Sema/SemaDeclCXX.cpp", 1722)
;
1723 }
1724}
1725
1726static bool CheckConstexprFunctionBody(Sema &SemaRef, const FunctionDecl *Dcl,
1727 Stmt *Body,
1728 Sema::CheckConstexprKind Kind);
1729
1730// Check whether a function declaration satisfies the requirements of a
1731// constexpr function definition or a constexpr constructor definition. If so,
1732// return true. If not, produce appropriate diagnostics (unless asked not to by
1733// Kind) and return false.
1734//
1735// This implements C++11 [dcl.constexpr]p3,4, as amended by DR1360.
1736bool Sema::CheckConstexprFunctionDefinition(const FunctionDecl *NewFD,
1737 CheckConstexprKind Kind) {
1738 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
1739 if (MD && MD->isInstance()) {
1740 // C++11 [dcl.constexpr]p4:
1741 // The definition of a constexpr constructor shall satisfy the following
1742 // constraints:
1743 // - the class shall not have any virtual base classes;
1744 //
1745 // FIXME: This only applies to constructors and destructors, not arbitrary
1746 // member functions.
1747 const CXXRecordDecl *RD = MD->getParent();
1748 if (RD->getNumVBases()) {
1749 if (Kind == CheckConstexprKind::CheckValid)
1750 return false;
1751
1752 Diag(NewFD->getLocation(), diag::err_constexpr_virtual_base)
1753 << isa<CXXConstructorDecl>(NewFD)
1754 << getRecordDiagFromTagKind(RD->getTagKind()) << RD->getNumVBases();
1755 for (const auto &I : RD->vbases())
1756 Diag(I.getBeginLoc(), diag::note_constexpr_virtual_base_here)
1757 << I.getSourceRange();
1758 return false;
1759 }
1760 }
1761
1762 if (!isa<CXXConstructorDecl>(NewFD)) {
1763 // C++11 [dcl.constexpr]p3:
1764 // The definition of a constexpr function shall satisfy the following
1765 // constraints:
1766 // - it shall not be virtual; (removed in C++20)
1767 const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD);
1768 if (Method && Method->isVirtual()) {
1769 if (getLangOpts().CPlusPlus20) {
1770 if (Kind == CheckConstexprKind::Diagnose)
1771 Diag(Method->getLocation(), diag::warn_cxx17_compat_constexpr_virtual);
1772 } else {
1773 if (Kind == CheckConstexprKind::CheckValid)
1774 return false;
1775
1776 Method = Method->getCanonicalDecl();
1777 Diag(Method->getLocation(), diag::err_constexpr_virtual);
1778
1779 // If it's not obvious why this function is virtual, find an overridden
1780 // function which uses the 'virtual' keyword.
1781 const CXXMethodDecl *WrittenVirtual = Method;
1782 while (!WrittenVirtual->isVirtualAsWritten())
1783 WrittenVirtual = *WrittenVirtual->begin_overridden_methods();
1784 if (WrittenVirtual != Method)
1785 Diag(WrittenVirtual->getLocation(),
1786 diag::note_overridden_virtual_function);
1787 return false;
1788 }
1789 }
1790
1791 // - its return type shall be a literal type;
1792 if (!CheckConstexprReturnType(*this, NewFD, Kind))
1793 return false;
1794 }
1795
1796 if (auto *Dtor = dyn_cast<CXXDestructorDecl>(NewFD)) {
1797 // A destructor can be constexpr only if the defaulted destructor could be;
1798 // we don't need to check the members and bases if we already know they all
1799 // have constexpr destructors.
1800 if (!Dtor->getParent()->defaultedDestructorIsConstexpr()) {
1801 if (Kind == CheckConstexprKind::CheckValid)
1802 return false;
1803 if (!CheckConstexprDestructorSubobjects(*this, Dtor, Kind))
1804 return false;
1805 }
1806 }
1807
1808 // - each of its parameter types shall be a literal type;
1809 if (!CheckConstexprParameterTypes(*this, NewFD, Kind))
1810 return false;
1811
1812 Stmt *Body = NewFD->getBody();
1813 assert(Body &&(static_cast <bool> (Body && "CheckConstexprFunctionDefinition called on function with no body"
) ? void (0) : __assert_fail ("Body && \"CheckConstexprFunctionDefinition called on function with no body\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 1814, __extension__ __PRETTY_FUNCTION__
))
1814 "CheckConstexprFunctionDefinition called on function with no body")(static_cast <bool> (Body && "CheckConstexprFunctionDefinition called on function with no body"
) ? void (0) : __assert_fail ("Body && \"CheckConstexprFunctionDefinition called on function with no body\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 1814, __extension__ __PRETTY_FUNCTION__
))
;
1815 return CheckConstexprFunctionBody(*this, NewFD, Body, Kind);
1816}
1817
1818/// Check the given declaration statement is legal within a constexpr function
1819/// body. C++11 [dcl.constexpr]p3,p4, and C++1y [dcl.constexpr]p3.
1820///
1821/// \return true if the body is OK (maybe only as an extension), false if we
1822/// have diagnosed a problem.
1823static bool CheckConstexprDeclStmt(Sema &SemaRef, const FunctionDecl *Dcl,
1824 DeclStmt *DS, SourceLocation &Cxx1yLoc,
1825 Sema::CheckConstexprKind Kind) {
1826 // C++11 [dcl.constexpr]p3 and p4:
1827 // The definition of a constexpr function(p3) or constructor(p4) [...] shall
1828 // contain only
1829 for (const auto *DclIt : DS->decls()) {
1830 switch (DclIt->getKind()) {
1831 case Decl::StaticAssert:
1832 case Decl::Using:
1833 case Decl::UsingShadow:
1834 case Decl::UsingDirective:
1835 case Decl::UnresolvedUsingTypename:
1836 case Decl::UnresolvedUsingValue:
1837 case Decl::UsingEnum:
1838 // - static_assert-declarations
1839 // - using-declarations,
1840 // - using-directives,
1841 // - using-enum-declaration
1842 continue;
1843
1844 case Decl::Typedef:
1845 case Decl::TypeAlias: {
1846 // - typedef declarations and alias-declarations that do not define
1847 // classes or enumerations,
1848 const auto *TN = cast<TypedefNameDecl>(DclIt);
1849 if (TN->getUnderlyingType()->isVariablyModifiedType()) {
1850 // Don't allow variably-modified types in constexpr functions.
1851 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1852 TypeLoc TL = TN->getTypeSourceInfo()->getTypeLoc();
1853 SemaRef.Diag(TL.getBeginLoc(), diag::err_constexpr_vla)
1854 << TL.getSourceRange() << TL.getType()
1855 << isa<CXXConstructorDecl>(Dcl);
1856 }
1857 return false;
1858 }
1859 continue;
1860 }
1861
1862 case Decl::Enum:
1863 case Decl::CXXRecord:
1864 // C++1y allows types to be defined, not just declared.
1865 if (cast<TagDecl>(DclIt)->isThisDeclarationADefinition()) {
1866 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1867 SemaRef.Diag(DS->getBeginLoc(),
1868 SemaRef.getLangOpts().CPlusPlus14
1869 ? diag::warn_cxx11_compat_constexpr_type_definition
1870 : diag::ext_constexpr_type_definition)
1871 << isa<CXXConstructorDecl>(Dcl);
1872 } else if (!SemaRef.getLangOpts().CPlusPlus14) {
1873 return false;
1874 }
1875 }
1876 continue;
1877
1878 case Decl::EnumConstant:
1879 case Decl::IndirectField:
1880 case Decl::ParmVar:
1881 // These can only appear with other declarations which are banned in
1882 // C++11 and permitted in C++1y, so ignore them.
1883 continue;
1884
1885 case Decl::Var:
1886 case Decl::Decomposition: {
1887 // C++1y [dcl.constexpr]p3 allows anything except:
1888 // a definition of a variable of non-literal type or of static or
1889 // thread storage duration or [before C++2a] for which no
1890 // initialization is performed.
1891 const auto *VD = cast<VarDecl>(DclIt);
1892 if (VD->isThisDeclarationADefinition()) {
1893 if (VD->isStaticLocal()) {
1894 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1895 SemaRef.Diag(VD->getLocation(),
1896 SemaRef.getLangOpts().CPlusPlus2b
1897 ? diag::warn_cxx20_compat_constexpr_var
1898 : diag::ext_constexpr_static_var)
1899 << isa<CXXConstructorDecl>(Dcl)
1900 << (VD->getTLSKind() == VarDecl::TLS_Dynamic);
1901 } else if (!SemaRef.getLangOpts().CPlusPlus2b) {
1902 return false;
1903 }
1904 }
1905 if (SemaRef.LangOpts.CPlusPlus2b) {
1906 CheckLiteralType(SemaRef, Kind, VD->getLocation(), VD->getType(),
1907 diag::warn_cxx20_compat_constexpr_var,
1908 isa<CXXConstructorDecl>(Dcl),
1909 /*variable of non-literal type*/ 2);
1910 } else if (CheckLiteralType(
1911 SemaRef, Kind, VD->getLocation(), VD->getType(),
1912 diag::err_constexpr_local_var_non_literal_type,
1913 isa<CXXConstructorDecl>(Dcl))) {
1914 return false;
1915 }
1916 if (!VD->getType()->isDependentType() &&
1917 !VD->hasInit() && !VD->isCXXForRangeDecl()) {
1918 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1919 SemaRef.Diag(
1920 VD->getLocation(),
1921 SemaRef.getLangOpts().CPlusPlus20
1922 ? diag::warn_cxx17_compat_constexpr_local_var_no_init
1923 : diag::ext_constexpr_local_var_no_init)
1924 << isa<CXXConstructorDecl>(Dcl);
1925 } else if (!SemaRef.getLangOpts().CPlusPlus20) {
1926 return false;
1927 }
1928 continue;
1929 }
1930 }
1931 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1932 SemaRef.Diag(VD->getLocation(),
1933 SemaRef.getLangOpts().CPlusPlus14
1934 ? diag::warn_cxx11_compat_constexpr_local_var
1935 : diag::ext_constexpr_local_var)
1936 << isa<CXXConstructorDecl>(Dcl);
1937 } else if (!SemaRef.getLangOpts().CPlusPlus14) {
1938 return false;
1939 }
1940 continue;
1941 }
1942
1943 case Decl::NamespaceAlias:
1944 case Decl::Function:
1945 // These are disallowed in C++11 and permitted in C++1y. Allow them
1946 // everywhere as an extension.
1947 if (!Cxx1yLoc.isValid())
1948 Cxx1yLoc = DS->getBeginLoc();
1949 continue;
1950
1951 default:
1952 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1953 SemaRef.Diag(DS->getBeginLoc(), diag::err_constexpr_body_invalid_stmt)
1954 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
1955 }
1956 return false;
1957 }
1958 }
1959
1960 return true;
1961}
1962
1963/// Check that the given field is initialized within a constexpr constructor.
1964///
1965/// \param Dcl The constexpr constructor being checked.
1966/// \param Field The field being checked. This may be a member of an anonymous
1967/// struct or union nested within the class being checked.
1968/// \param Inits All declarations, including anonymous struct/union members and
1969/// indirect members, for which any initialization was provided.
1970/// \param Diagnosed Whether we've emitted the error message yet. Used to attach
1971/// multiple notes for different members to the same error.
1972/// \param Kind Whether we're diagnosing a constructor as written or determining
1973/// whether the formal requirements are satisfied.
1974/// \return \c false if we're checking for validity and the constructor does
1975/// not satisfy the requirements on a constexpr constructor.
1976static bool CheckConstexprCtorInitializer(Sema &SemaRef,
1977 const FunctionDecl *Dcl,
1978 FieldDecl *Field,
1979 llvm::SmallSet<Decl*, 16> &Inits,
1980 bool &Diagnosed,
1981 Sema::CheckConstexprKind Kind) {
1982 // In C++20 onwards, there's nothing to check for validity.
1983 if (Kind == Sema::CheckConstexprKind::CheckValid &&
1984 SemaRef.getLangOpts().CPlusPlus20)
1985 return true;
1986
1987 if (Field->isInvalidDecl())
1988 return true;
1989
1990 if (Field->isUnnamedBitfield())
1991 return true;
1992
1993 // Anonymous unions with no variant members and empty anonymous structs do not
1994 // need to be explicitly initialized. FIXME: Anonymous structs that contain no
1995 // indirect fields don't need initializing.
1996 if (Field->isAnonymousStructOrUnion() &&
1997 (Field->getType()->isUnionType()
1998 ? !Field->getType()->getAsCXXRecordDecl()->hasVariantMembers()
1999 : Field->getType()->getAsCXXRecordDecl()->isEmpty()))
2000 return true;
2001
2002 if (!Inits.count(Field)) {
2003 if (Kind == Sema::CheckConstexprKind::Diagnose) {
2004 if (!Diagnosed) {
2005 SemaRef.Diag(Dcl->getLocation(),
2006 SemaRef.getLangOpts().CPlusPlus20
2007 ? diag::warn_cxx17_compat_constexpr_ctor_missing_init
2008 : diag::ext_constexpr_ctor_missing_init);
2009 Diagnosed = true;
2010 }
2011 SemaRef.Diag(Field->getLocation(),
2012 diag::note_constexpr_ctor_missing_init);
2013 } else if (!SemaRef.getLangOpts().CPlusPlus20) {
2014 return false;
2015 }
2016 } else if (Field->isAnonymousStructOrUnion()) {
2017 const RecordDecl *RD = Field->getType()->castAs<RecordType>()->getDecl();
2018 for (auto *I : RD->fields())
2019 // If an anonymous union contains an anonymous struct of which any member
2020 // is initialized, all members must be initialized.
2021 if (!RD->isUnion() || Inits.count(I))
2022 if (!CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed,
2023 Kind))
2024 return false;
2025 }
2026 return true;
2027}
2028
2029/// Check the provided statement is allowed in a constexpr function
2030/// definition.
2031static bool
2032CheckConstexprFunctionStmt(Sema &SemaRef, const FunctionDecl *Dcl, Stmt *S,
2033 SmallVectorImpl<SourceLocation> &ReturnStmts,
2034 SourceLocation &Cxx1yLoc, SourceLocation &Cxx2aLoc,
2035 SourceLocation &Cxx2bLoc,
2036 Sema::CheckConstexprKind Kind) {
2037 // - its function-body shall be [...] a compound-statement that contains only
2038 switch (S->getStmtClass()) {
2039 case Stmt::NullStmtClass:
2040 // - null statements,
2041 return true;
2042
2043 case Stmt::DeclStmtClass:
2044 // - static_assert-declarations
2045 // - using-declarations,
2046 // - using-directives,
2047 // - typedef declarations and alias-declarations that do not define
2048 // classes or enumerations,
2049 if (!CheckConstexprDeclStmt(SemaRef, Dcl, cast<DeclStmt>(S), Cxx1yLoc, Kind))
2050 return false;
2051 return true;
2052
2053 case Stmt::ReturnStmtClass:
2054 // - and exactly one return statement;
2055 if (isa<CXXConstructorDecl>(Dcl)) {
2056 // C++1y allows return statements in constexpr constructors.
2057 if (!Cxx1yLoc.isValid())
2058 Cxx1yLoc = S->getBeginLoc();
2059 return true;
2060 }
2061
2062 ReturnStmts.push_back(S->getBeginLoc());
2063 return true;
2064
2065 case Stmt::AttributedStmtClass:
2066 // Attributes on a statement don't affect its formal kind and hence don't
2067 // affect its validity in a constexpr function.
2068 return CheckConstexprFunctionStmt(
2069 SemaRef, Dcl, cast<AttributedStmt>(S)->getSubStmt(), ReturnStmts,
2070 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind);
2071
2072 case Stmt::CompoundStmtClass: {
2073 // C++1y allows compound-statements.
2074 if (!Cxx1yLoc.isValid())
2075 Cxx1yLoc = S->getBeginLoc();
2076
2077 CompoundStmt *CompStmt = cast<CompoundStmt>(S);
2078 for (auto *BodyIt : CompStmt->body()) {
2079 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, BodyIt, ReturnStmts,
2080 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2081 return false;
2082 }
2083 return true;
2084 }
2085
2086 case Stmt::IfStmtClass: {
2087 // C++1y allows if-statements.
2088 if (!Cxx1yLoc.isValid())
2089 Cxx1yLoc = S->getBeginLoc();
2090
2091 IfStmt *If = cast<IfStmt>(S);
2092 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, If->getThen(), ReturnStmts,
2093 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2094 return false;
2095 if (If->getElse() &&
2096 !CheckConstexprFunctionStmt(SemaRef, Dcl, If->getElse(), ReturnStmts,
2097 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2098 return false;
2099 return true;
2100 }
2101
2102 case Stmt::WhileStmtClass:
2103 case Stmt::DoStmtClass:
2104 case Stmt::ForStmtClass:
2105 case Stmt::CXXForRangeStmtClass:
2106 case Stmt::ContinueStmtClass:
2107 // C++1y allows all of these. We don't allow them as extensions in C++11,
2108 // because they don't make sense without variable mutation.
2109 if (!SemaRef.getLangOpts().CPlusPlus14)
2110 break;
2111 if (!Cxx1yLoc.isValid())
2112 Cxx1yLoc = S->getBeginLoc();
2113 for (Stmt *SubStmt : S->children()) {
2114 if (SubStmt &&
2115 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2116 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2117 return false;
2118 }
2119 return true;
2120
2121 case Stmt::SwitchStmtClass:
2122 case Stmt::CaseStmtClass:
2123 case Stmt::DefaultStmtClass:
2124 case Stmt::BreakStmtClass:
2125 // C++1y allows switch-statements, and since they don't need variable
2126 // mutation, we can reasonably allow them in C++11 as an extension.
2127 if (!Cxx1yLoc.isValid())
2128 Cxx1yLoc = S->getBeginLoc();
2129 for (Stmt *SubStmt : S->children()) {
2130 if (SubStmt &&
2131 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2132 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2133 return false;
2134 }
2135 return true;
2136
2137 case Stmt::LabelStmtClass:
2138 case Stmt::GotoStmtClass:
2139 if (Cxx2bLoc.isInvalid())
2140 Cxx2bLoc = S->getBeginLoc();
2141 for (Stmt *SubStmt : S->children()) {
2142 if (SubStmt &&
2143 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2144 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2145 return false;
2146 }
2147 return true;
2148
2149 case Stmt::GCCAsmStmtClass:
2150 case Stmt::MSAsmStmtClass:
2151 // C++2a allows inline assembly statements.
2152 case Stmt::CXXTryStmtClass:
2153 if (Cxx2aLoc.isInvalid())
2154 Cxx2aLoc = S->getBeginLoc();
2155 for (Stmt *SubStmt : S->children()) {
2156 if (SubStmt &&
2157 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2158 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2159 return false;
2160 }
2161 return true;
2162
2163 case Stmt::CXXCatchStmtClass:
2164 // Do not bother checking the language mode (already covered by the
2165 // try block check).
2166 if (!CheckConstexprFunctionStmt(
2167 SemaRef, Dcl, cast<CXXCatchStmt>(S)->getHandlerBlock(), ReturnStmts,
2168 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2169 return false;
2170 return true;
2171
2172 default:
2173 if (!isa<Expr>(S))
2174 break;
2175
2176 // C++1y allows expression-statements.
2177 if (!Cxx1yLoc.isValid())
2178 Cxx1yLoc = S->getBeginLoc();
2179 return true;
2180 }
2181
2182 if (Kind == Sema::CheckConstexprKind::Diagnose) {
2183 SemaRef.Diag(S->getBeginLoc(), diag::err_constexpr_body_invalid_stmt)
2184 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
2185 }
2186 return false;
2187}
2188
2189/// Check the body for the given constexpr function declaration only contains
2190/// the permitted types of statement. C++11 [dcl.constexpr]p3,p4.
2191///
2192/// \return true if the body is OK, false if we have found or diagnosed a
2193/// problem.
2194static bool CheckConstexprFunctionBody(Sema &SemaRef, const FunctionDecl *Dcl,
2195 Stmt *Body,
2196 Sema::CheckConstexprKind Kind) {
2197 SmallVector<SourceLocation, 4> ReturnStmts;
2198
2199 if (isa<CXXTryStmt>(Body)) {
2200 // C++11 [dcl.constexpr]p3:
2201 // The definition of a constexpr function shall satisfy the following
2202 // constraints: [...]
2203 // - its function-body shall be = delete, = default, or a
2204 // compound-statement
2205 //
2206 // C++11 [dcl.constexpr]p4:
2207 // In the definition of a constexpr constructor, [...]
2208 // - its function-body shall not be a function-try-block;
2209 //
2210 // This restriction is lifted in C++2a, as long as inner statements also
2211 // apply the general constexpr rules.
2212 switch (Kind) {
2213 case Sema::CheckConstexprKind::CheckValid:
2214 if (!SemaRef.getLangOpts().CPlusPlus20)
2215 return false;
2216 break;
2217
2218 case Sema::CheckConstexprKind::Diagnose:
2219 SemaRef.Diag(Body->getBeginLoc(),
2220 !SemaRef.getLangOpts().CPlusPlus20
2221 ? diag::ext_constexpr_function_try_block_cxx20
2222 : diag::warn_cxx17_compat_constexpr_function_try_block)
2223 << isa<CXXConstructorDecl>(Dcl);
2224 break;
2225 }
2226 }
2227
2228 // - its function-body shall be [...] a compound-statement that contains only
2229 // [... list of cases ...]
2230 //
2231 // Note that walking the children here is enough to properly check for
2232 // CompoundStmt and CXXTryStmt body.
2233 SourceLocation Cxx1yLoc, Cxx2aLoc, Cxx2bLoc;
2234 for (Stmt *SubStmt : Body->children()) {
2235 if (SubStmt &&
2236 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2237 Cxx1yLoc, Cxx2aLoc, Cxx2bLoc, Kind))
2238 return false;
2239 }
2240
2241 if (Kind == Sema::CheckConstexprKind::CheckValid) {
2242 // If this is only valid as an extension, report that we don't satisfy the
2243 // constraints of the current language.
2244 if ((Cxx2bLoc.isValid() && !SemaRef.getLangOpts().CPlusPlus2b) ||
2245 (Cxx2aLoc.isValid() && !SemaRef.getLangOpts().CPlusPlus20) ||
2246 (Cxx1yLoc.isValid() && !SemaRef.getLangOpts().CPlusPlus17))
2247 return false;
2248 } else if (Cxx2bLoc.isValid()) {
2249 SemaRef.Diag(Cxx2bLoc,
2250 SemaRef.getLangOpts().CPlusPlus2b
2251 ? diag::warn_cxx20_compat_constexpr_body_invalid_stmt
2252 : diag::ext_constexpr_body_invalid_stmt_cxx2b)
2253 << isa<CXXConstructorDecl>(Dcl);
2254 } else if (Cxx2aLoc.isValid()) {
2255 SemaRef.Diag(Cxx2aLoc,
2256 SemaRef.getLangOpts().CPlusPlus20
2257 ? diag::warn_cxx17_compat_constexpr_body_invalid_stmt
2258 : diag::ext_constexpr_body_invalid_stmt_cxx20)
2259 << isa<CXXConstructorDecl>(Dcl);
2260 } else if (Cxx1yLoc.isValid()) {
2261 SemaRef.Diag(Cxx1yLoc,
2262 SemaRef.getLangOpts().CPlusPlus14
2263 ? diag::warn_cxx11_compat_constexpr_body_invalid_stmt
2264 : diag::ext_constexpr_body_invalid_stmt)
2265 << isa<CXXConstructorDecl>(Dcl);
2266 }
2267
2268 if (const CXXConstructorDecl *Constructor
2269 = dyn_cast<CXXConstructorDecl>(Dcl)) {
2270 const CXXRecordDecl *RD = Constructor->getParent();
2271 // DR1359:
2272 // - every non-variant non-static data member and base class sub-object
2273 // shall be initialized;
2274 // DR1460:
2275 // - if the class is a union having variant members, exactly one of them
2276 // shall be initialized;
2277 if (RD->isUnion()) {
2278 if (Constructor->getNumCtorInitializers() == 0 &&
2279 RD->hasVariantMembers()) {
2280 if (Kind == Sema::CheckConstexprKind::Diagnose) {
2281 SemaRef.Diag(
2282 Dcl->getLocation(),
2283 SemaRef.getLangOpts().CPlusPlus20
2284 ? diag::warn_cxx17_compat_constexpr_union_ctor_no_init
2285 : diag::ext_constexpr_union_ctor_no_init);
2286 } else if (!SemaRef.getLangOpts().CPlusPlus20) {
2287 return false;
2288 }
2289 }
2290 } else if (!Constructor->isDependentContext() &&
2291 !Constructor->isDelegatingConstructor()) {
2292 assert(RD->getNumVBases() == 0 && "constexpr ctor with virtual bases")(static_cast <bool> (RD->getNumVBases() == 0 &&
"constexpr ctor with virtual bases") ? void (0) : __assert_fail
("RD->getNumVBases() == 0 && \"constexpr ctor with virtual bases\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2292, __extension__ __PRETTY_FUNCTION__
))
;
2293
2294 // Skip detailed checking if we have enough initializers, and we would
2295 // allow at most one initializer per member.
2296 bool AnyAnonStructUnionMembers = false;
2297 unsigned Fields = 0;
2298 for (CXXRecordDecl::field_iterator I = RD->field_begin(),
2299 E = RD->field_end(); I != E; ++I, ++Fields) {
2300 if (I->isAnonymousStructOrUnion()) {
2301 AnyAnonStructUnionMembers = true;
2302 break;
2303 }
2304 }
2305 // DR1460:
2306 // - if the class is a union-like class, but is not a union, for each of
2307 // its anonymous union members having variant members, exactly one of
2308 // them shall be initialized;
2309 if (AnyAnonStructUnionMembers ||
2310 Constructor->getNumCtorInitializers() != RD->getNumBases() + Fields) {
2311 // Check initialization of non-static data members. Base classes are
2312 // always initialized so do not need to be checked. Dependent bases
2313 // might not have initializers in the member initializer list.
2314 llvm::SmallSet<Decl*, 16> Inits;
2315 for (const auto *I: Constructor->inits()) {
2316 if (FieldDecl *FD = I->getMember())
2317 Inits.insert(FD);
2318 else if (IndirectFieldDecl *ID = I->getIndirectMember())
2319 Inits.insert(ID->chain_begin(), ID->chain_end());
2320 }
2321
2322 bool Diagnosed = false;
2323 for (auto *I : RD->fields())
2324 if (!CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed,
2325 Kind))
2326 return false;
2327 }
2328 }
2329 } else {
2330 if (ReturnStmts.empty()) {
2331 // C++1y doesn't require constexpr functions to contain a 'return'
2332 // statement. We still do, unless the return type might be void, because
2333 // otherwise if there's no return statement, the function cannot
2334 // be used in a core constant expression.
2335 bool OK = SemaRef.getLangOpts().CPlusPlus14 &&
2336 (Dcl->getReturnType()->isVoidType() ||
2337 Dcl->getReturnType()->isDependentType());
2338 switch (Kind) {
2339 case Sema::CheckConstexprKind::Diagnose:
2340 SemaRef.Diag(Dcl->getLocation(),
2341 OK ? diag::warn_cxx11_compat_constexpr_body_no_return
2342 : diag::err_constexpr_body_no_return)
2343 << Dcl->isConsteval();
2344 if (!OK)
2345 return false;
2346 break;
2347
2348 case Sema::CheckConstexprKind::CheckValid:
2349 // The formal requirements don't include this rule in C++14, even
2350 // though the "must be able to produce a constant expression" rules
2351 // still imply it in some cases.
2352 if (!SemaRef.getLangOpts().CPlusPlus14)
2353 return false;
2354 break;
2355 }
2356 } else if (ReturnStmts.size() > 1) {
2357 switch (Kind) {
2358 case Sema::CheckConstexprKind::Diagnose:
2359 SemaRef.Diag(
2360 ReturnStmts.back(),
2361 SemaRef.getLangOpts().CPlusPlus14
2362 ? diag::warn_cxx11_compat_constexpr_body_multiple_return
2363 : diag::ext_constexpr_body_multiple_return);
2364 for (unsigned I = 0; I < ReturnStmts.size() - 1; ++I)
2365 SemaRef.Diag(ReturnStmts[I],
2366 diag::note_constexpr_body_previous_return);
2367 break;
2368
2369 case Sema::CheckConstexprKind::CheckValid:
2370 if (!SemaRef.getLangOpts().CPlusPlus14)
2371 return false;
2372 break;
2373 }
2374 }
2375 }
2376
2377 // C++11 [dcl.constexpr]p5:
2378 // if no function argument values exist such that the function invocation
2379 // substitution would produce a constant expression, the program is
2380 // ill-formed; no diagnostic required.
2381 // C++11 [dcl.constexpr]p3:
2382 // - every constructor call and implicit conversion used in initializing the
2383 // return value shall be one of those allowed in a constant expression.
2384 // C++11 [dcl.constexpr]p4:
2385 // - every constructor involved in initializing non-static data members and
2386 // base class sub-objects shall be a constexpr constructor.
2387 //
2388 // Note that this rule is distinct from the "requirements for a constexpr
2389 // function", so is not checked in CheckValid mode.
2390 SmallVector<PartialDiagnosticAt, 8> Diags;
2391 if (Kind == Sema::CheckConstexprKind::Diagnose &&
2392 !Expr::isPotentialConstantExpr(Dcl, Diags)) {
2393 SemaRef.Diag(Dcl->getLocation(),
2394 diag::ext_constexpr_function_never_constant_expr)
2395 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
2396 for (size_t I = 0, N = Diags.size(); I != N; ++I)
2397 SemaRef.Diag(Diags[I].first, Diags[I].second);
2398 // Don't return false here: we allow this for compatibility in
2399 // system headers.
2400 }
2401
2402 return true;
2403}
2404
2405/// Get the class that is directly named by the current context. This is the
2406/// class for which an unqualified-id in this scope could name a constructor
2407/// or destructor.
2408///
2409/// If the scope specifier denotes a class, this will be that class.
2410/// If the scope specifier is empty, this will be the class whose
2411/// member-specification we are currently within. Otherwise, there
2412/// is no such class.
2413CXXRecordDecl *Sema::getCurrentClass(Scope *, const CXXScopeSpec *SS) {
2414 assert(getLangOpts().CPlusPlus && "No class names in C!")(static_cast <bool> (getLangOpts().CPlusPlus &&
"No class names in C!") ? void (0) : __assert_fail ("getLangOpts().CPlusPlus && \"No class names in C!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2414, __extension__ __PRETTY_FUNCTION__
))
;
2415
2416 if (SS && SS->isInvalid())
2417 return nullptr;
2418
2419 if (SS && SS->isNotEmpty()) {
2420 DeclContext *DC = computeDeclContext(*SS, true);
2421 return dyn_cast_or_null<CXXRecordDecl>(DC);
2422 }
2423
2424 return dyn_cast_or_null<CXXRecordDecl>(CurContext);
2425}
2426
2427/// isCurrentClassName - Determine whether the identifier II is the
2428/// name of the class type currently being defined. In the case of
2429/// nested classes, this will only return true if II is the name of
2430/// the innermost class.
2431bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *S,
2432 const CXXScopeSpec *SS) {
2433 CXXRecordDecl *CurDecl = getCurrentClass(S, SS);
2434 return CurDecl && &II == CurDecl->getIdentifier();
2435}
2436
2437/// Determine whether the identifier II is a typo for the name of
2438/// the class type currently being defined. If so, update it to the identifier
2439/// that should have been used.
2440bool Sema::isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS) {
2441 assert(getLangOpts().CPlusPlus && "No class names in C!")(static_cast <bool> (getLangOpts().CPlusPlus &&
"No class names in C!") ? void (0) : __assert_fail ("getLangOpts().CPlusPlus && \"No class names in C!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2441, __extension__ __PRETTY_FUNCTION__
))
;
2442
2443 if (!getLangOpts().SpellChecking)
2444 return false;
2445
2446 CXXRecordDecl *CurDecl;
2447 if (SS && SS->isSet() && !SS->isInvalid()) {
2448 DeclContext *DC = computeDeclContext(*SS, true);
2449 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
2450 } else
2451 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
2452
2453 if (CurDecl && CurDecl->getIdentifier() && II != CurDecl->getIdentifier() &&
2454 3 * II->getName().edit_distance(CurDecl->getIdentifier()->getName())
2455 < II->getLength()) {
2456 II = CurDecl->getIdentifier();
2457 return true;
2458 }
2459
2460 return false;
2461}
2462
2463/// Determine whether the given class is a base class of the given
2464/// class, including looking at dependent bases.
2465static bool findCircularInheritance(const CXXRecordDecl *Class,
2466 const CXXRecordDecl *Current) {
2467 SmallVector<const CXXRecordDecl*, 8> Queue;
2468
2469 Class = Class->getCanonicalDecl();
2470 while (true) {
2471 for (const auto &I : Current->bases()) {
2472 CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
2473 if (!Base)
2474 continue;
2475
2476 Base = Base->getDefinition();
2477 if (!Base)
2478 continue;
2479
2480 if (Base->getCanonicalDecl() == Class)
2481 return true;
2482
2483 Queue.push_back(Base);
2484 }
2485
2486 if (Queue.empty())
2487 return false;
2488
2489 Current = Queue.pop_back_val();
2490 }
2491
2492 return false;
2493}
2494
2495/// Check the validity of a C++ base class specifier.
2496///
2497/// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics
2498/// and returns NULL otherwise.
2499CXXBaseSpecifier *
2500Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
2501 SourceRange SpecifierRange,
2502 bool Virtual, AccessSpecifier Access,
2503 TypeSourceInfo *TInfo,
2504 SourceLocation EllipsisLoc) {
2505 // In HLSL, unspecified class access is public rather than private.
2506 if (getLangOpts().HLSL && Class->getTagKind() == TTK_Class &&
2507 Access == AS_none)
2508 Access = AS_public;
2509
2510 QualType BaseType = TInfo->getType();
2511 if (BaseType->containsErrors()) {
2512 // Already emitted a diagnostic when parsing the error type.
2513 return nullptr;
2514 }
2515 // C++ [class.union]p1:
2516 // A union shall not have base classes.
2517 if (Class->isUnion()) {
2518 Diag(Class->getLocation(), diag::err_base_clause_on_union)
2519 << SpecifierRange;
2520 return nullptr;
2521 }
2522
2523 if (EllipsisLoc.isValid() &&
2524 !TInfo->getType()->containsUnexpandedParameterPack()) {
2525 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
2526 << TInfo->getTypeLoc().getSourceRange();
2527 EllipsisLoc = SourceLocation();
2528 }
2529
2530 SourceLocation BaseLoc = TInfo->getTypeLoc().getBeginLoc();
2531
2532 if (BaseType->isDependentType()) {
2533 // Make sure that we don't have circular inheritance among our dependent
2534 // bases. For non-dependent bases, the check for completeness below handles
2535 // this.
2536 if (CXXRecordDecl *BaseDecl = BaseType->getAsCXXRecordDecl()) {
2537 if (BaseDecl->getCanonicalDecl() == Class->getCanonicalDecl() ||
2538 ((BaseDecl = BaseDecl->getDefinition()) &&
2539 findCircularInheritance(Class, BaseDecl))) {
2540 Diag(BaseLoc, diag::err_circular_inheritance)
2541 << BaseType << Context.getTypeDeclType(Class);
2542
2543 if (BaseDecl->getCanonicalDecl() != Class->getCanonicalDecl())
2544 Diag(BaseDecl->getLocation(), diag::note_previous_decl)
2545 << BaseType;
2546
2547 return nullptr;
2548 }
2549 }
2550
2551 // Make sure that we don't make an ill-formed AST where the type of the
2552 // Class is non-dependent and its attached base class specifier is an
2553 // dependent type, which violates invariants in many clang code paths (e.g.
2554 // constexpr evaluator). If this case happens (in errory-recovery mode), we
2555 // explicitly mark the Class decl invalid. The diagnostic was already
2556 // emitted.
2557 if (!Class->getTypeForDecl()->isDependentType())
2558 Class->setInvalidDecl();
2559 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2560 Class->getTagKind() == TTK_Class,
2561 Access, TInfo, EllipsisLoc);
2562 }
2563
2564 // Base specifiers must be record types.
2565 if (!BaseType->isRecordType()) {
2566 Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange;
2567 return nullptr;
2568 }
2569
2570 // C++ [class.union]p1:
2571 // A union shall not be used as a base class.
2572 if (BaseType->isUnionType()) {
2573 Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange;
2574 return nullptr;
2575 }
2576
2577 // For the MS ABI, propagate DLL attributes to base class templates.
2578 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2579 if (Attr *ClassAttr = getDLLAttr(Class)) {
2580 if (auto *BaseTemplate = dyn_cast_or_null<ClassTemplateSpecializationDecl>(
2581 BaseType->getAsCXXRecordDecl())) {
2582 propagateDLLAttrToBaseClassTemplate(Class, ClassAttr, BaseTemplate,
2583 BaseLoc);
2584 }
2585 }
2586 }
2587
2588 // C++ [class.derived]p2:
2589 // The class-name in a base-specifier shall not be an incompletely
2590 // defined class.
2591 if (RequireCompleteType(BaseLoc, BaseType,
2592 diag::err_incomplete_base_class, SpecifierRange)) {
2593 Class->setInvalidDecl();
2594 return nullptr;
2595 }
2596
2597 // If the base class is polymorphic or isn't empty, the new one is/isn't, too.
2598 RecordDecl *BaseDecl = BaseType->castAs<RecordType>()->getDecl();
2599 assert(BaseDecl && "Record type has no declaration")(static_cast <bool> (BaseDecl && "Record type has no declaration"
) ? void (0) : __assert_fail ("BaseDecl && \"Record type has no declaration\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2599, __extension__ __PRETTY_FUNCTION__
))
;
2600 BaseDecl = BaseDecl->getDefinition();
2601 assert(BaseDecl && "Base type is not incomplete, but has no definition")(static_cast <bool> (BaseDecl && "Base type is not incomplete, but has no definition"
) ? void (0) : __assert_fail ("BaseDecl && \"Base type is not incomplete, but has no definition\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2601, __extension__ __PRETTY_FUNCTION__
))
;
2602 CXXRecordDecl *CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
2603 assert(CXXBaseDecl && "Base type is not a C++ type")(static_cast <bool> (CXXBaseDecl && "Base type is not a C++ type"
) ? void (0) : __assert_fail ("CXXBaseDecl && \"Base type is not a C++ type\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2603, __extension__ __PRETTY_FUNCTION__
))
;
2604
2605 // Microsoft docs say:
2606 // "If a base-class has a code_seg attribute, derived classes must have the
2607 // same attribute."
2608 const auto *BaseCSA = CXXBaseDecl->getAttr<CodeSegAttr>();
2609 const auto *DerivedCSA = Class->getAttr<CodeSegAttr>();
2610 if ((DerivedCSA || BaseCSA) &&
2611 (!BaseCSA || !DerivedCSA || BaseCSA->getName() != DerivedCSA->getName())) {
2612 Diag(Class->getLocation(), diag::err_mismatched_code_seg_base);
2613 Diag(CXXBaseDecl->getLocation(), diag::note_base_class_specified_here)
2614 << CXXBaseDecl;
2615 return nullptr;
2616 }
2617
2618 // A class which contains a flexible array member is not suitable for use as a
2619 // base class:
2620 // - If the layout determines that a base comes before another base,
2621 // the flexible array member would index into the subsequent base.
2622 // - If the layout determines that base comes before the derived class,
2623 // the flexible array member would index into the derived class.
2624 if (CXXBaseDecl->hasFlexibleArrayMember()) {
2625 Diag(BaseLoc, diag::err_base_class_has_flexible_array_member)
2626 << CXXBaseDecl->getDeclName();
2627 return nullptr;
2628 }
2629
2630 // C++ [class]p3:
2631 // If a class is marked final and it appears as a base-type-specifier in
2632 // base-clause, the program is ill-formed.
2633 if (FinalAttr *FA = CXXBaseDecl->getAttr<FinalAttr>()) {
2634 Diag(BaseLoc, diag::err_class_marked_final_used_as_base)
2635 << CXXBaseDecl->getDeclName()
2636 << FA->isSpelledAsSealed();
2637 Diag(CXXBaseDecl->getLocation(), diag::note_entity_declared_at)
2638 << CXXBaseDecl->getDeclName() << FA->getRange();
2639 return nullptr;
2640 }
2641
2642 if (BaseDecl->isInvalidDecl())
2643 Class->setInvalidDecl();
2644
2645 // Create the base specifier.
2646 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2647 Class->getTagKind() == TTK_Class,
2648 Access, TInfo, EllipsisLoc);
2649}
2650
2651/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is
2652/// one entry in the base class list of a class specifier, for
2653/// example:
2654/// class foo : public bar, virtual private baz {
2655/// 'public bar' and 'virtual private baz' are each base-specifiers.
2656BaseResult Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
2657 const ParsedAttributesView &Attributes,
2658 bool Virtual, AccessSpecifier Access,
2659 ParsedType basetype, SourceLocation BaseLoc,
2660 SourceLocation EllipsisLoc) {
2661 if (!classdecl)
2662 return true;
2663
2664 AdjustDeclIfTemplate(classdecl);
2665 CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(classdecl);
2666 if (!Class)
2667 return true;
2668
2669 // We haven't yet attached the base specifiers.
2670 Class->setIsParsingBaseSpecifiers();
2671
2672 // We do not support any C++11 attributes on base-specifiers yet.
2673 // Diagnose any attributes we see.
2674 for (const ParsedAttr &AL : Attributes) {
2675 if (AL.isInvalid() || AL.getKind() == ParsedAttr::IgnoredAttribute)
2676 continue;
2677 Diag(AL.getLoc(), AL.getKind() == ParsedAttr::UnknownAttribute
2678 ? (unsigned)diag::warn_unknown_attribute_ignored
2679 : (unsigned)diag::err_base_specifier_attribute)
2680 << AL << AL.getRange();
2681 }
2682
2683 TypeSourceInfo *TInfo = nullptr;
2684 GetTypeFromParser(basetype, &TInfo);
2685
2686 if (EllipsisLoc.isInvalid() &&
2687 DiagnoseUnexpandedParameterPack(SpecifierRange.getBegin(), TInfo,
2688 UPPC_BaseType))
2689 return true;
2690
2691 if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange,
2692 Virtual, Access, TInfo,
2693 EllipsisLoc))
2694 return BaseSpec;
2695 else
2696 Class->setInvalidDecl();
2697
2698 return true;
2699}
2700
2701/// Use small set to collect indirect bases. As this is only used
2702/// locally, there's no need to abstract the small size parameter.
2703typedef llvm::SmallPtrSet<QualType, 4> IndirectBaseSet;
2704
2705/// Recursively add the bases of Type. Don't add Type itself.
2706static void
2707NoteIndirectBases(ASTContext &Context, IndirectBaseSet &Set,
2708 const QualType &Type)
2709{
2710 // Even though the incoming type is a base, it might not be
2711 // a class -- it could be a template parm, for instance.
2712 if (auto Rec = Type->getAs<RecordType>()) {
2713 auto Decl = Rec->getAsCXXRecordDecl();
2714
2715 // Iterate over its bases.
2716 for (const auto &BaseSpec : Decl->bases()) {
2717 QualType Base = Context.getCanonicalType(BaseSpec.getType())
2718 .getUnqualifiedType();
2719 if (Set.insert(Base).second)
2720 // If we've not already seen it, recurse.
2721 NoteIndirectBases(Context, Set, Base);
2722 }
2723 }
2724}
2725
2726/// Performs the actual work of attaching the given base class
2727/// specifiers to a C++ class.
2728bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class,
2729 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2730 if (Bases.empty())
2731 return false;
2732
2733 // Used to keep track of which base types we have already seen, so
2734 // that we can properly diagnose redundant direct base types. Note
2735 // that the key is always the unqualified canonical type of the base
2736 // class.
2737 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes;
2738
2739 // Used to track indirect bases so we can see if a direct base is
2740 // ambiguous.
2741 IndirectBaseSet IndirectBaseTypes;
2742
2743 // Copy non-redundant base specifiers into permanent storage.
2744 unsigned NumGoodBases = 0;
2745 bool Invalid = false;
2746 for (unsigned idx = 0; idx < Bases.size(); ++idx) {
2747 QualType NewBaseType
2748 = Context.getCanonicalType(Bases[idx]->getType());
2749 NewBaseType = NewBaseType.getLocalUnqualifiedType();
2750
2751 CXXBaseSpecifier *&KnownBase = KnownBaseTypes[NewBaseType];
2752 if (KnownBase) {
2753 // C++ [class.mi]p3:
2754 // A class shall not be specified as a direct base class of a
2755 // derived class more than once.
2756 Diag(Bases[idx]->getBeginLoc(), diag::err_duplicate_base_class)
2757 << KnownBase->getType() << Bases[idx]->getSourceRange();
2758
2759 // Delete the duplicate base class specifier; we're going to
2760 // overwrite its pointer later.
2761 Context.Deallocate(Bases[idx]);
2762
2763 Invalid = true;
2764 } else {
2765 // Okay, add this new base class.
2766 KnownBase = Bases[idx];
2767 Bases[NumGoodBases++] = Bases[idx];
2768
2769 if (NewBaseType->isDependentType())
2770 continue;
2771 // Note this base's direct & indirect bases, if there could be ambiguity.
2772 if (Bases.size() > 1)
2773 NoteIndirectBases(Context, IndirectBaseTypes, NewBaseType);
2774
2775 if (const RecordType *Record = NewBaseType->getAs<RecordType>()) {
2776 const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
2777 if (Class->isInterface() &&
2778 (!RD->isInterfaceLike() ||
2779 KnownBase->getAccessSpecifier() != AS_public)) {
2780 // The Microsoft extension __interface does not permit bases that
2781 // are not themselves public interfaces.
2782 Diag(KnownBase->getBeginLoc(), diag::err_invalid_base_in_interface)
2783 << getRecordDiagFromTagKind(RD->getTagKind()) << RD
2784 << RD->getSourceRange();
2785 Invalid = true;
2786 }
2787 if (RD->hasAttr<WeakAttr>())
2788 Class->addAttr(WeakAttr::CreateImplicit(Context));
2789 }
2790 }
2791 }
2792
2793 // Attach the remaining base class specifiers to the derived class.
2794 Class->setBases(Bases.data(), NumGoodBases);
2795
2796 // Check that the only base classes that are duplicate are virtual.
2797 for (unsigned idx = 0; idx < NumGoodBases; ++idx) {
2798 // Check whether this direct base is inaccessible due to ambiguity.
2799 QualType BaseType = Bases[idx]->getType();
2800
2801 // Skip all dependent types in templates being used as base specifiers.
2802 // Checks below assume that the base specifier is a CXXRecord.
2803 if (BaseType->isDependentType())
2804 continue;
2805
2806 CanQualType CanonicalBase = Context.getCanonicalType(BaseType)
2807 .getUnqualifiedType();
2808
2809 if (IndirectBaseTypes.count(CanonicalBase)) {
2810 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2811 /*DetectVirtual=*/true);
2812 bool found
2813 = Class->isDerivedFrom(CanonicalBase->getAsCXXRecordDecl(), Paths);
2814 assert(found)(static_cast <bool> (found) ? void (0) : __assert_fail (
"found", "clang/lib/Sema/SemaDeclCXX.cpp", 2814, __extension__
__PRETTY_FUNCTION__))
;
2815 (void)found;
2816
2817 if (Paths.isAmbiguous(CanonicalBase))
2818 Diag(Bases[idx]->getBeginLoc(), diag::warn_inaccessible_base_class)
2819 << BaseType << getAmbiguousPathsDisplayString(Paths)
2820 << Bases[idx]->getSourceRange();
2821 else
2822 assert(Bases[idx]->isVirtual())(static_cast <bool> (Bases[idx]->isVirtual()) ? void
(0) : __assert_fail ("Bases[idx]->isVirtual()", "clang/lib/Sema/SemaDeclCXX.cpp"
, 2822, __extension__ __PRETTY_FUNCTION__))
;
2823 }
2824
2825 // Delete the base class specifier, since its data has been copied
2826 // into the CXXRecordDecl.
2827 Context.Deallocate(Bases[idx]);
2828 }
2829
2830 return Invalid;
2831}
2832
2833/// ActOnBaseSpecifiers - Attach the given base specifiers to the
2834/// class, after checking whether there are any duplicate base
2835/// classes.
2836void Sema::ActOnBaseSpecifiers(Decl *ClassDecl,
2837 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2838 if (!ClassDecl || Bases.empty())
2839 return;
2840
2841 AdjustDeclIfTemplate(ClassDecl);
2842 AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl), Bases);
2843}
2844
2845/// Determine whether the type \p Derived is a C++ class that is
2846/// derived from the type \p Base.
2847bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base) {
2848 if (!getLangOpts().CPlusPlus)
2849 return false;
2850
2851 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2852 if (!DerivedRD)
2853 return false;
2854
2855 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2856 if (!BaseRD)
2857 return false;
2858
2859 // If either the base or the derived type is invalid, don't try to
2860 // check whether one is derived from the other.
2861 if (BaseRD->isInvalidDecl() || DerivedRD->isInvalidDecl())
2862 return false;
2863
2864 // FIXME: In a modules build, do we need the entire path to be visible for us
2865 // to be able to use the inheritance relationship?
2866 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2867 return false;
2868
2869 return DerivedRD->isDerivedFrom(BaseRD);
2870}
2871
2872/// Determine whether the type \p Derived is a C++ class that is
2873/// derived from the type \p Base.
2874bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base,
2875 CXXBasePaths &Paths) {
2876 if (!getLangOpts().CPlusPlus)
2877 return false;
2878
2879 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2880 if (!DerivedRD)
2881 return false;
2882
2883 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2884 if (!BaseRD)
2885 return false;
2886
2887 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2888 return false;
2889
2890 return DerivedRD->isDerivedFrom(BaseRD, Paths);
2891}
2892
2893static void BuildBasePathArray(const CXXBasePath &Path,
2894 CXXCastPath &BasePathArray) {
2895 // We first go backward and check if we have a virtual base.
2896 // FIXME: It would be better if CXXBasePath had the base specifier for
2897 // the nearest virtual base.
2898 unsigned Start = 0;
2899 for (unsigned I = Path.size(); I != 0; --I) {
2900 if (Path[I - 1].Base->isVirtual()) {
2901 Start = I - 1;
2902 break;
2903 }
2904 }
2905
2906 // Now add all bases.
2907 for (unsigned I = Start, E = Path.size(); I != E; ++I)
2908 BasePathArray.push_back(const_cast<CXXBaseSpecifier*>(Path[I].Base));
2909}
2910
2911
2912void Sema::BuildBasePathArray(const CXXBasePaths &Paths,
2913 CXXCastPath &BasePathArray) {
2914 assert(BasePathArray.empty() && "Base path array must be empty!")(static_cast <bool> (BasePathArray.empty() && "Base path array must be empty!"
) ? void (0) : __assert_fail ("BasePathArray.empty() && \"Base path array must be empty!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2914, __extension__ __PRETTY_FUNCTION__
))
;
2915 assert(Paths.isRecordingPaths() && "Must record paths!")(static_cast <bool> (Paths.isRecordingPaths() &&
"Must record paths!") ? void (0) : __assert_fail ("Paths.isRecordingPaths() && \"Must record paths!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2915, __extension__ __PRETTY_FUNCTION__
))
;
2916 return ::BuildBasePathArray(Paths.front(), BasePathArray);
2917}
2918/// CheckDerivedToBaseConversion - Check whether the Derived-to-Base
2919/// conversion (where Derived and Base are class types) is
2920/// well-formed, meaning that the conversion is unambiguous (and
2921/// that all of the base classes are accessible). Returns true
2922/// and emits a diagnostic if the code is ill-formed, returns false
2923/// otherwise. Loc is the location where this routine should point to
2924/// if there is an error, and Range is the source range to highlight
2925/// if there is an error.
2926///
2927/// If either InaccessibleBaseID or AmbiguousBaseConvID are 0, then the
2928/// diagnostic for the respective type of error will be suppressed, but the
2929/// check for ill-formed code will still be performed.
2930bool
2931Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2932 unsigned InaccessibleBaseID,
2933 unsigned AmbiguousBaseConvID,
2934 SourceLocation Loc, SourceRange Range,
2935 DeclarationName Name,
2936 CXXCastPath *BasePath,
2937 bool IgnoreAccess) {
2938 // First, determine whether the path from Derived to Base is
2939 // ambiguous. This is slightly more expensive than checking whether
2940 // the Derived to Base conversion exists, because here we need to
2941 // explore multiple paths to determine if there is an ambiguity.
2942 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2943 /*DetectVirtual=*/false);
2944 bool DerivationOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2945 if (!DerivationOkay)
2946 return true;
2947
2948 const CXXBasePath *Path = nullptr;
2949 if (!Paths.isAmbiguous(Context.getCanonicalType(Base).getUnqualifiedType()))
2950 Path = &Paths.front();
2951
2952 // For MSVC compatibility, check if Derived directly inherits from Base. Clang
2953 // warns about this hierarchy under -Winaccessible-base, but MSVC allows the
2954 // user to access such bases.
2955 if (!Path && getLangOpts().MSVCCompat) {
2956 for (const CXXBasePath &PossiblePath : Paths) {
2957 if (PossiblePath.size() == 1) {
2958 Path = &PossiblePath;
2959 if (AmbiguousBaseConvID)
2960 Diag(Loc, diag::ext_ms_ambiguous_direct_base)
2961 << Base << Derived << Range;
2962 break;
2963 }
2964 }
2965 }
2966
2967 if (Path) {
2968 if (!IgnoreAccess) {
2969 // Check that the base class can be accessed.
2970 switch (
2971 CheckBaseClassAccess(Loc, Base, Derived, *Path, InaccessibleBaseID)) {
2972 case AR_inaccessible:
2973 return true;
2974 case AR_accessible:
2975 case AR_dependent:
2976 case AR_delayed:
2977 break;
2978 }
2979 }
2980
2981 // Build a base path if necessary.
2982 if (BasePath)
2983 ::BuildBasePathArray(*Path, *BasePath);
2984 return false;
2985 }
2986
2987 if (AmbiguousBaseConvID) {
2988 // We know that the derived-to-base conversion is ambiguous, and
2989 // we're going to produce a diagnostic. Perform the derived-to-base
2990 // search just one more time to compute all of the possible paths so
2991 // that we can print them out. This is more expensive than any of
2992 // the previous derived-to-base checks we've done, but at this point
2993 // performance isn't as much of an issue.
2994 Paths.clear();
2995 Paths.setRecordingPaths(true);
2996 bool StillOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2997 assert(StillOkay && "Can only be used with a derived-to-base conversion")(static_cast <bool> (StillOkay && "Can only be used with a derived-to-base conversion"
) ? void (0) : __assert_fail ("StillOkay && \"Can only be used with a derived-to-base conversion\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 2997, __extension__ __PRETTY_FUNCTION__
))
;
2998 (void)StillOkay;
2999
3000 // Build up a textual representation of the ambiguous paths, e.g.,
3001 // D -> B -> A, that will be used to illustrate the ambiguous
3002 // conversions in the diagnostic. We only print one of the paths
3003 // to each base class subobject.
3004 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
3005
3006 Diag(Loc, AmbiguousBaseConvID)
3007 << Derived << Base << PathDisplayStr << Range << Name;
3008 }
3009 return true;
3010}
3011
3012bool
3013Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
3014 SourceLocation Loc, SourceRange Range,
3015 CXXCastPath *BasePath,
3016 bool IgnoreAccess) {
3017 return CheckDerivedToBaseConversion(
3018 Derived, Base, diag::err_upcast_to_inaccessible_base,
3019 diag::err_ambiguous_derived_to_base_conv, Loc, Range, DeclarationName(),
3020 BasePath, IgnoreAccess);
3021}
3022
3023
3024/// Builds a string representing ambiguous paths from a
3025/// specific derived class to different subobjects of the same base
3026/// class.
3027///
3028/// This function builds a string that can be used in error messages
3029/// to show the different paths that one can take through the
3030/// inheritance hierarchy to go from the derived class to different
3031/// subobjects of a base class. The result looks something like this:
3032/// @code
3033/// struct D -> struct B -> struct A
3034/// struct D -> struct C -> struct A
3035/// @endcode
3036std::string Sema::getAmbiguousPathsDisplayString(CXXBasePaths &Paths) {
3037 std::string PathDisplayStr;
3038 std::set<unsigned> DisplayedPaths;
3039 for (CXXBasePaths::paths_iterator Path = Paths.begin();
3040 Path != Paths.end(); ++Path) {
3041 if (DisplayedPaths.insert(Path->back().SubobjectNumber).second) {
3042 // We haven't displayed a path to this particular base
3043 // class subobject yet.
3044 PathDisplayStr += "\n ";
3045 PathDisplayStr += Context.getTypeDeclType(Paths.getOrigin()).getAsString();
3046 for (CXXBasePath::const_iterator Element = Path->begin();
3047 Element != Path->end(); ++Element)
3048 PathDisplayStr += " -> " + Element->Base->getType().getAsString();
3049 }
3050 }
3051
3052 return PathDisplayStr;
3053}
3054
3055//===----------------------------------------------------------------------===//
3056// C++ class member Handling
3057//===----------------------------------------------------------------------===//
3058
3059/// ActOnAccessSpecifier - Parsed an access specifier followed by a colon.
3060bool Sema::ActOnAccessSpecifier(AccessSpecifier Access, SourceLocation ASLoc,
3061 SourceLocation ColonLoc,
3062 const ParsedAttributesView &Attrs) {
3063 assert(Access != AS_none && "Invalid kind for syntactic access specifier!")(static_cast <bool> (Access != AS_none && "Invalid kind for syntactic access specifier!"
) ? void (0) : __assert_fail ("Access != AS_none && \"Invalid kind for syntactic access specifier!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 3063, __extension__ __PRETTY_FUNCTION__
))
;
3064 AccessSpecDecl *ASDecl = AccessSpecDecl::Create(Context, Access, CurContext,
3065 ASLoc, ColonLoc);
3066 CurContext->addHiddenDecl(ASDecl);
3067 return ProcessAccessDeclAttributeList(ASDecl, Attrs);
3068}
3069
3070/// CheckOverrideControl - Check C++11 override control semantics.
3071void Sema::CheckOverrideControl(NamedDecl *D) {
3072 if (D->isInvalidDecl())
3073 return;
3074
3075 // We only care about "override" and "final" declarations.
3076 if (!D->hasAttr<OverrideAttr>() && !D->hasAttr<FinalAttr>())
3077 return;
3078
3079 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
3080
3081 // We can't check dependent instance methods.
3082 if (MD && MD->isInstance() &&
3083 (MD->getParent()->hasAnyDependentBases() ||
3084 MD->getType()->isDependentType()))
3085 return;
3086
3087 if (MD && !MD->isVirtual()) {
3088 // If we have a non-virtual method, check if if hides a virtual method.
3089 // (In that case, it's most likely the method has the wrong type.)
3090 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
3091 FindHiddenVirtualMethods(MD, OverloadedMethods);
3092
3093 if (!OverloadedMethods.empty()) {
3094 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
3095 Diag(OA->getLocation(),
3096 diag::override_keyword_hides_virtual_member_function)
3097 << "override" << (OverloadedMethods.size() > 1);
3098 } else if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
3099 Diag(FA->getLocation(),
3100 diag::override_keyword_hides_virtual_member_function)
3101 << (FA->isSpelledAsSealed() ? "sealed" : "final")
3102 << (OverloadedMethods.size() > 1);
3103 }
3104 NoteHiddenVirtualMethods(MD, OverloadedMethods);
3105 MD->setInvalidDecl();
3106 return;
3107 }
3108 // Fall through into the general case diagnostic.
3109 // FIXME: We might want to attempt typo correction here.
3110 }
3111
3112 if (!MD || !MD->isVirtual()) {
3113 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
3114 Diag(OA->getLocation(),
3115 diag::override_keyword_only_allowed_on_virtual_member_functions)
3116 << "override" << FixItHint::CreateRemoval(OA->getLocation());
3117 D->dropAttr<OverrideAttr>();
3118 }
3119 if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
3120 Diag(FA->getLocation(),
3121 diag::override_keyword_only_allowed_on_virtual_member_functions)
3122 << (FA->isSpelledAsSealed() ? "sealed" : "final")
3123 << FixItHint::CreateRemoval(FA->getLocation());
3124 D->dropAttr<FinalAttr>();
3125 }
3126 return;
3127 }
3128
3129 // C++11 [class.virtual]p5:
3130 // If a function is marked with the virt-specifier override and
3131 // does not override a member function of a base class, the program is
3132 // ill-formed.
3133 bool HasOverriddenMethods = MD->size_overridden_methods() != 0;
3134 if (MD->hasAttr<OverrideAttr>() && !HasOverriddenMethods)
3135 Diag(MD->getLocation(), diag::err_function_marked_override_not_overriding)
3136 << MD->getDeclName();
3137}
3138
3139void Sema::DiagnoseAbsenceOfOverrideControl(NamedDecl *D, bool Inconsistent) {
3140 if (D->isInvalidDecl() || D->hasAttr<OverrideAttr>())
3141 return;
3142 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
3143 if (!MD || MD->isImplicit() || MD->hasAttr<FinalAttr>())
3144 return;
3145
3146 SourceLocation Loc = MD->getLocation();
3147 SourceLocation SpellingLoc = Loc;
3148 if (getSourceManager().isMacroArgExpansion(Loc))
3149 SpellingLoc = getSourceManager().getImmediateExpansionRange(Loc).getBegin();
3150 SpellingLoc = getSourceManager().getSpellingLoc(SpellingLoc);
3151 if (SpellingLoc.isValid() && getSourceManager().isInSystemHeader(SpellingLoc))
3152 return;
3153
3154 if (MD->size_overridden_methods() > 0) {
3155 auto EmitDiag = [&](unsigned DiagInconsistent, unsigned DiagSuggest) {
3156 unsigned DiagID =
3157 Inconsistent && !Diags.isIgnored(DiagInconsistent, MD->getLocation())
3158 ? DiagInconsistent
3159 : DiagSuggest;
3160 Diag(MD->getLocation(), DiagID) << MD->getDeclName();
3161 const CXXMethodDecl *OMD = *MD->begin_overridden_methods();
3162 Diag(OMD->getLocation(), diag::note_overridden_virtual_function);
3163 };
3164 if (isa<CXXDestructorDecl>(MD))
3165 EmitDiag(
3166 diag::warn_inconsistent_destructor_marked_not_override_overriding,
3167 diag::warn_suggest_destructor_marked_not_override_overriding);
3168 else
3169 EmitDiag(diag::warn_inconsistent_function_marked_not_override_overriding,
3170 diag::warn_suggest_function_marked_not_override_overriding);
3171 }
3172}
3173
3174/// CheckIfOverriddenFunctionIsMarkedFinal - Checks whether a virtual member
3175/// function overrides a virtual member function marked 'final', according to
3176/// C++11 [class.virtual]p4.
3177bool Sema::CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
3178 const CXXMethodDecl *Old) {
3179 FinalAttr *FA = Old->getAttr<FinalAttr>();
3180 if (!FA)
3181 return false;
3182
3183 Diag(New->getLocation(), diag::err_final_function_overridden)
3184 << New->getDeclName()
3185 << FA->isSpelledAsSealed();
3186 Diag(Old->getLocation(), diag::note_overridden_virtual_function);
3187 return true;
3188}
3189
3190static bool InitializationHasSideEffects(const FieldDecl &FD) {
3191 const Type *T = FD.getType()->getBaseElementTypeUnsafe();
3192 // FIXME: Destruction of ObjC lifetime types has side-effects.
3193 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3194 return !RD->isCompleteDefinition() ||
3195 !RD->hasTrivialDefaultConstructor() ||
3196 !RD->hasTrivialDestructor();
3197 return false;
3198}
3199
3200static const ParsedAttr *getMSPropertyAttr(const ParsedAttributesView &list) {
3201 ParsedAttributesView::const_iterator Itr =
3202 llvm::find_if(list, [](const ParsedAttr &AL) {
3203 return AL.isDeclspecPropertyAttribute();
3204 });
3205 if (Itr != list.end())
3206 return &*Itr;
3207 return nullptr;
3208}
3209
3210// Check if there is a field shadowing.
3211void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,
3212 DeclarationName FieldName,
3213 const CXXRecordDecl *RD,
3214 bool DeclIsField) {
3215 if (Diags.isIgnored(diag::warn_shadow_field, Loc))
3216 return;
3217
3218 // To record a shadowed field in a base
3219 std::map<CXXRecordDecl*, NamedDecl*> Bases;
3220 auto FieldShadowed = [&](const CXXBaseSpecifier *Specifier,
3221 CXXBasePath &Path) {
3222 const auto Base = Specifier->getType()->getAsCXXRecordDecl();
3223 // Record an ambiguous path directly
3224 if (Bases.find(Base) != Bases.end())
3225 return true;
3226 for (const auto Field : Base->lookup(FieldName)) {
3227 if ((isa<FieldDecl>(Field) || isa<IndirectFieldDecl>(Field)) &&
3228 Field->getAccess() != AS_private) {
3229 assert(Field->getAccess() != AS_none)(static_cast <bool> (Field->getAccess() != AS_none) ?
void (0) : __assert_fail ("Field->getAccess() != AS_none"
, "clang/lib/Sema/SemaDeclCXX.cpp", 3229, __extension__ __PRETTY_FUNCTION__
))
;
3230 assert(Bases.find(Base) == Bases.end())(static_cast <bool> (Bases.find(Base) == Bases.end()) ?
void (0) : __assert_fail ("Bases.find(Base) == Bases.end()",
"clang/lib/Sema/SemaDeclCXX.cpp", 3230, __extension__ __PRETTY_FUNCTION__
))
;
3231 Bases[Base] = Field;
3232 return true;
3233 }
3234 }
3235 return false;
3236 };
3237
3238 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
3239 /*DetectVirtual=*/true);
3240 if (!RD->lookupInBases(FieldShadowed, Paths))
3241 return;
3242
3243 for (const auto &P : Paths) {
3244 auto Base = P.back().Base->getType()->getAsCXXRecordDecl();
3245 auto It = Bases.find(Base);
3246 // Skip duplicated bases
3247 if (It == Bases.end())
3248 continue;
3249 auto BaseField = It->second;
3250 assert(BaseField->getAccess() != AS_private)(static_cast <bool> (BaseField->getAccess() != AS_private
) ? void (0) : __assert_fail ("BaseField->getAccess() != AS_private"
, "clang/lib/Sema/SemaDeclCXX.cpp", 3250, __extension__ __PRETTY_FUNCTION__
))
;
3251 if (AS_none !=
3252 CXXRecordDecl::MergeAccess(P.Access, BaseField->getAccess())) {
3253 Diag(Loc, diag::warn_shadow_field)
3254 << FieldName << RD << Base << DeclIsField;
3255 Diag(BaseField->getLocation(), diag::note_shadow_field);
3256 Bases.erase(It);
3257 }
3258 }
3259}
3260
3261/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member
3262/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the
3263/// bitfield width if there is one, 'InitExpr' specifies the initializer if
3264/// one has been parsed, and 'InitStyle' is set if an in-class initializer is
3265/// present (but parsing it has been deferred).
3266NamedDecl *
3267Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D,
3268 MultiTemplateParamsArg TemplateParameterLists,
3269 Expr *BW, const VirtSpecifiers &VS,
3270 InClassInitStyle InitStyle) {
3271 const DeclSpec &DS = D.getDeclSpec();
3272 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
3273 DeclarationName Name = NameInfo.getName();
3274 SourceLocation Loc = NameInfo.getLoc();
3275
3276 // For anonymous bitfields, the location should point to the type.
3277 if (Loc.isInvalid())
3278 Loc = D.getBeginLoc();
3279
3280 Expr *BitWidth = static_cast<Expr*>(BW);
3281
3282 assert(isa<CXXRecordDecl>(CurContext))(static_cast <bool> (isa<CXXRecordDecl>(CurContext
)) ? void (0) : __assert_fail ("isa<CXXRecordDecl>(CurContext)"
, "clang/lib/Sema/SemaDeclCXX.cpp", 3282, __extension__ __PRETTY_FUNCTION__
))
;
3283 assert(!DS.isFriendSpecified())(static_cast <bool> (!DS.isFriendSpecified()) ? void (0
) : __assert_fail ("!DS.isFriendSpecified()", "clang/lib/Sema/SemaDeclCXX.cpp"
, 3283, __extension__ __PRETTY_FUNCTION__))
;
3284
3285 bool isFunc = D.isDeclarationOfFunction();
3286 const ParsedAttr *MSPropertyAttr =
3287 getMSPropertyAttr(D.getDeclSpec().getAttributes());
3288
3289 if (cast<CXXRecordDecl>(CurContext)->isInterface()) {
3290 // The Microsoft extension __interface only permits public member functions
3291 // and prohibits constructors, destructors, operators, non-public member
3292 // functions, static methods and data members.
3293 unsigned InvalidDecl;
3294 bool ShowDeclName = true;
3295 if (!isFunc &&
3296 (DS.getStorageClassSpec() == DeclSpec::SCS_typedef || MSPropertyAttr))
3297 InvalidDecl = 0;
3298 else if (!isFunc)
3299 InvalidDecl = 1;
3300 else if (AS != AS_public)
3301 InvalidDecl = 2;
3302 else if (DS.getStorageClassSpec() == DeclSpec::SCS_static)
3303 InvalidDecl = 3;
3304 else switch (Name.getNameKind()) {
3305 case DeclarationName::CXXConstructorName:
3306 InvalidDecl = 4;
3307 ShowDeclName = false;
3308 break;
3309
3310 case DeclarationName::CXXDestructorName:
3311 InvalidDecl = 5;
3312 ShowDeclName = false;
3313 break;
3314
3315 case DeclarationName::CXXOperatorName:
3316 case DeclarationName::CXXConversionFunctionName:
3317 InvalidDecl = 6;
3318 break;
3319
3320 default:
3321 InvalidDecl = 0;
3322 break;
3323 }
3324
3325 if (InvalidDecl) {
3326 if (ShowDeclName)
3327 Diag(Loc, diag::err_invalid_member_in_interface)
3328 << (InvalidDecl-1) << Name;
3329 else
3330 Diag(Loc, diag::err_invalid_member_in_interface)
3331 << (InvalidDecl-1) << "";
3332 return nullptr;
3333 }
3334 }
3335
3336 // C++ 9.2p6: A member shall not be declared to have automatic storage
3337 // duration (auto, register) or with the extern storage-class-specifier.
3338 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class
3339 // data members and cannot be applied to names declared const or static,
3340 // and cannot be applied to reference members.
3341 switch (DS.getStorageClassSpec()) {
3342 case DeclSpec::SCS_unspecified:
3343 case DeclSpec::SCS_typedef:
3344 case DeclSpec::SCS_static:
3345 break;
3346 case DeclSpec::SCS_mutable:
3347 if (isFunc) {
3348 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function);
3349
3350 // FIXME: It would be nicer if the keyword was ignored only for this
3351 // declarator. Otherwise we could get follow-up errors.
3352 D.getMutableDeclSpec().ClearStorageClassSpecs();
3353 }
3354 break;
3355 default:
3356 Diag(DS.getStorageClassSpecLoc(),
3357 diag::err_storageclass_invalid_for_member);
3358 D.getMutableDeclSpec().ClearStorageClassSpecs();
3359 break;
3360 }
3361
3362 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified ||
3363 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) &&
3364 !isFunc);
3365
3366 if (DS.hasConstexprSpecifier() && isInstField) {
3367 SemaDiagnosticBuilder B =
3368 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr_member);
3369 SourceLocation ConstexprLoc = DS.getConstexprSpecLoc();
3370 if (InitStyle == ICIS_NoInit) {
3371 B << 0 << 0;
3372 if (D.getDeclSpec().getTypeQualifiers() & DeclSpec::TQ_const)
3373 B << FixItHint::CreateRemoval(ConstexprLoc);
3374 else {
3375 B << FixItHint::CreateReplacement(ConstexprLoc, "const");
3376 D.getMutableDeclSpec().ClearConstexprSpec();
3377 const char *PrevSpec;
3378 unsigned DiagID;
3379 bool Failed = D.getMutableDeclSpec().SetTypeQual(
3380 DeclSpec::TQ_const, ConstexprLoc, PrevSpec, DiagID, getLangOpts());
3381 (void)Failed;
3382 assert(!Failed && "Making a constexpr member const shouldn't fail")(static_cast <bool> (!Failed && "Making a constexpr member const shouldn't fail"
) ? void (0) : __assert_fail ("!Failed && \"Making a constexpr member const shouldn't fail\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 3382, __extension__ __PRETTY_FUNCTION__
))
;
3383 }
3384 } else {
3385 B << 1;
3386 const char *PrevSpec;
3387 unsigned DiagID;
3388 if (D.getMutableDeclSpec().SetStorageClassSpec(
3389 *this, DeclSpec::SCS_static, ConstexprLoc, PrevSpec, DiagID,
3390 Context.getPrintingPolicy())) {
3391 assert(DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&(static_cast <bool> (DS.getStorageClassSpec() == DeclSpec
::SCS_mutable && "This is the only DeclSpec that should fail to be applied"
) ? void (0) : __assert_fail ("DS.getStorageClassSpec() == DeclSpec::SCS_mutable && \"This is the only DeclSpec that should fail to be applied\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 3392, __extension__ __PRETTY_FUNCTION__
))
3392 "This is the only DeclSpec that should fail to be applied")(static_cast <bool> (DS.getStorageClassSpec() == DeclSpec
::SCS_mutable && "This is the only DeclSpec that should fail to be applied"
) ? void (0) : __assert_fail ("DS.getStorageClassSpec() == DeclSpec::SCS_mutable && \"This is the only DeclSpec that should fail to be applied\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 3392, __extension__ __PRETTY_FUNCTION__
))
;
3393 B << 1;
3394 } else {
3395 B << 0 << FixItHint::CreateInsertion(ConstexprLoc, "static ");
3396 isInstField = false;
3397 }
3398 }
3399 }
3400
3401 NamedDecl *Member;
3402 if (isInstField) {
3403 CXXScopeSpec &SS = D.getCXXScopeSpec();
3404
3405 // Data members must have identifiers for names.
3406 if (!Name.isIdentifier()) {
3407 Diag(Loc, diag::err_bad_variable_name)
3408 << Name;
3409 return nullptr;
3410 }
3411
3412 IdentifierInfo *II = Name.getAsIdentifierInfo();
3413
3414 // Member field could not be with "template" keyword.
3415 // So TemplateParameterLists should be empty in this case.
3416 if (TemplateParameterLists.size()) {
3417 TemplateParameterList* TemplateParams = TemplateParameterLists[0];
3418 if (TemplateParams->size()) {
3419 // There is no such thing as a member field template.
3420 Diag(D.getIdentifierLoc(), diag::err_template_member)
3421 << II
3422 << SourceRange(TemplateParams->getTemplateLoc(),
3423 TemplateParams->getRAngleLoc());
3424 } else {
3425 // There is an extraneous 'template<>' for this member.
3426 Diag(TemplateParams->getTemplateLoc(),
3427 diag::err_template_member_noparams)
3428 << II
3429 << SourceRange(TemplateParams->getTemplateLoc(),
3430 TemplateParams->getRAngleLoc());
3431 }
3432 return nullptr;
3433 }
3434
3435 if (D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId) {
3436 Diag(D.getIdentifierLoc(), diag::err_member_with_template_arguments)
3437 << II
3438 << SourceRange(D.getName().TemplateId->LAngleLoc,
3439 D.getName().TemplateId->RAngleLoc)
3440 << D.getName().TemplateId->LAngleLoc;
3441 D.SetIdentifier(II, Loc);
3442 }
3443
3444 if (SS.isSet() && !SS.isInvalid()) {
3445 // The user provided a superfluous scope specifier inside a class
3446 // definition:
3447 //
3448 // class X {
3449 // int X::member;
3450 // };
3451 if (DeclContext *DC = computeDeclContext(SS, false))
3452 diagnoseQualifiedDeclaration(SS, DC, Name, D.getIdentifierLoc(),
3453 D.getName().getKind() ==
3454 UnqualifiedIdKind::IK_TemplateId);
3455 else
3456 Diag(D.getIdentifierLoc(), diag::err_member_qualification)
3457 << Name << SS.getRange();
3458
3459 SS.clear();
3460 }
3461
3462 if (MSPropertyAttr) {
3463 Member = HandleMSProperty(S, cast<CXXRecordDecl>(CurContext), Loc, D,
3464 BitWidth, InitStyle, AS, *MSPropertyAttr);
3465 if (!Member)
3466 return nullptr;
3467 isInstField = false;
3468 } else {
3469 Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D,
3470 BitWidth, InitStyle, AS);
3471 if (!Member)
3472 return nullptr;
3473 }
3474
3475 CheckShadowInheritedFields(Loc, Name, cast<CXXRecordDecl>(CurContext));
3476 } else {
3477 Member = HandleDeclarator(S, D, TemplateParameterLists);
3478 if (!Member)
3479 return nullptr;
3480
3481 // Non-instance-fields can't have a bitfield.
3482 if (BitWidth) {
3483 if (Member->isInvalidDecl()) {
3484 // don't emit another diagnostic.
3485 } else if (isa<VarDecl>(Member) || isa<VarTemplateDecl>(Member)) {
3486 // C++ 9.6p3: A bit-field shall not be a static member.
3487 // "static member 'A' cannot be a bit-field"
3488 Diag(Loc, diag::err_static_not_bitfield)
3489 << Name << BitWidth->getSourceRange();
3490 } else if (isa<TypedefDecl>(Member)) {
3491 // "typedef member 'x' cannot be a bit-field"
3492 Diag(Loc, diag::err_typedef_not_bitfield)
3493 << Name << BitWidth->getSourceRange();
3494 } else {
3495 // A function typedef ("typedef int f(); f a;").
3496 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
3497 Diag(Loc, diag::err_not_integral_type_bitfield)
3498 << Name << cast<ValueDecl>(Member)->getType()
3499 << BitWidth->getSourceRange();
3500 }
3501
3502 BitWidth = nullptr;
3503 Member->setInvalidDecl();
3504 }
3505
3506 NamedDecl *NonTemplateMember = Member;
3507 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Member))
3508 NonTemplateMember = FunTmpl->getTemplatedDecl();
3509 else if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(Member))
3510 NonTemplateMember = VarTmpl->getTemplatedDecl();
3511
3512 Member->setAccess(AS);
3513
3514 // If we have declared a member function template or static data member
3515 // template, set the access of the templated declaration as well.
3516 if (NonTemplateMember != Member)
3517 NonTemplateMember->setAccess(AS);
3518
3519 // C++ [temp.deduct.guide]p3:
3520 // A deduction guide [...] for a member class template [shall be
3521 // declared] with the same access [as the template].
3522 if (auto *DG = dyn_cast<CXXDeductionGuideDecl>(NonTemplateMember)) {
3523 auto *TD = DG->getDeducedTemplate();
3524 // Access specifiers are only meaningful if both the template and the
3525 // deduction guide are from the same scope.
3526 if (AS != TD->getAccess() &&
3527 TD->getDeclContext()->getRedeclContext()->Equals(
3528 DG->getDeclContext()->getRedeclContext())) {
3529 Diag(DG->getBeginLoc(), diag::err_deduction_guide_wrong_access);
3530 Diag(TD->getBeginLoc(), diag::note_deduction_guide_template_access)
3531 << TD->getAccess();
3532 const AccessSpecDecl *LastAccessSpec = nullptr;
3533 for (const auto *D : cast<CXXRecordDecl>(CurContext)->decls()) {
3534 if (const auto *AccessSpec = dyn_cast<AccessSpecDecl>(D))
3535 LastAccessSpec = AccessSpec;
3536 }
3537 assert(LastAccessSpec && "differing access with no access specifier")(static_cast <bool> (LastAccessSpec && "differing access with no access specifier"
) ? void (0) : __assert_fail ("LastAccessSpec && \"differing access with no access specifier\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 3537, __extension__ __PRETTY_FUNCTION__
))
;
3538 Diag(LastAccessSpec->getBeginLoc(), diag::note_deduction_guide_access)
3539 << AS;
3540 }
3541 }
3542 }
3543
3544 if (VS.isOverrideSpecified())
3545 Member->addAttr(OverrideAttr::Create(Context, VS.getOverrideLoc(),
3546 AttributeCommonInfo::AS_Keyword));
3547 if (VS.isFinalSpecified())
3548 Member->addAttr(FinalAttr::Create(
3549 Context, VS.getFinalLoc(), AttributeCommonInfo::AS_Keyword,
3550 static_cast<FinalAttr::Spelling>(VS.isFinalSpelledSealed())));
3551
3552 if (VS.getLastLocation().isValid()) {
3553 // Update the end location of a method that has a virt-specifiers.
3554 if (CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Member))
3555 MD->setRangeEnd(VS.getLastLocation());
3556 }
3557
3558 CheckOverrideControl(Member);
3559
3560 assert((Name || isInstField) && "No identifier for non-field ?")(static_cast <bool> ((Name || isInstField) && "No identifier for non-field ?"
) ? void (0) : __assert_fail ("(Name || isInstField) && \"No identifier for non-field ?\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 3560, __extension__ __PRETTY_FUNCTION__
))
;
3561
3562 if (isInstField) {
3563 FieldDecl *FD = cast<FieldDecl>(Member);
3564 FieldCollector->Add(FD);
3565
3566 if (!Diags.isIgnored(diag::warn_unused_private_field, FD->getLocation())) {
3567 // Remember all explicit private FieldDecls that have a name, no side
3568 // effects and are not part of a dependent type declaration.
3569 if (!FD->isImplicit() && FD->getDeclName() &&
3570 FD->getAccess() == AS_private &&
3571 !FD->hasAttr<UnusedAttr>() &&
3572 !FD->getParent()->isDependentContext() &&
3573 !InitializationHasSideEffects(*FD))
3574 UnusedPrivateFields.insert(FD);
3575 }
3576 }
3577
3578 return Member;
3579}
3580
3581namespace {
3582 class UninitializedFieldVisitor
3583 : public EvaluatedExprVisitor<UninitializedFieldVisitor> {
3584 Sema &S;
3585 // List of Decls to generate a warning on. Also remove Decls that become
3586 // initialized.
3587 llvm::SmallPtrSetImpl<ValueDecl*> &Decls;
3588 // List of base classes of the record. Classes are removed after their
3589 // initializers.
3590 llvm::SmallPtrSetImpl<QualType> &BaseClasses;
3591 // Vector of decls to be removed from the Decl set prior to visiting the
3592 // nodes. These Decls may have been initialized in the prior initializer.
3593 llvm::SmallVector<ValueDecl*, 4> DeclsToRemove;
3594 // If non-null, add a note to the warning pointing back to the constructor.
3595 const CXXConstructorDecl *Constructor;
3596 // Variables to hold state when processing an initializer list. When
3597 // InitList is true, special case initialization of FieldDecls matching
3598 // InitListFieldDecl.
3599 bool InitList;
3600 FieldDecl *InitListFieldDecl;
3601 llvm::SmallVector<unsigned, 4> InitFieldIndex;
3602
3603 public:
3604 typedef EvaluatedExprVisitor<UninitializedFieldVisitor> Inherited;
3605 UninitializedFieldVisitor(Sema &S,
3606 llvm::SmallPtrSetImpl<ValueDecl*> &Decls,
3607 llvm::SmallPtrSetImpl<QualType> &BaseClasses)
3608 : Inherited(S.Context), S(S), Decls(Decls), BaseClasses(BaseClasses),
3609 Constructor(nullptr), InitList(false), InitListFieldDecl(nullptr) {}
3610
3611 // Returns true if the use of ME is not an uninitialized use.
3612 bool IsInitListMemberExprInitialized(MemberExpr *ME,
3613 bool CheckReferenceOnly) {
3614 llvm::SmallVector<FieldDecl*, 4> Fields;
3615 bool ReferenceField = false;
3616 while (ME) {
3617 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
3618 if (!FD)
3619 return false;
3620 Fields.push_back(FD);
3621 if (FD->getType()->isReferenceType())
3622 ReferenceField = true;
3623 ME = dyn_cast<MemberExpr>(ME->getBase()->IgnoreParenImpCasts());
3624 }
3625
3626 // Binding a reference to an uninitialized field is not an
3627 // uninitialized use.
3628 if (CheckReferenceOnly && !ReferenceField)
3629 return true;
3630
3631 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
3632 // Discard the first field since it is the field decl that is being
3633 // initialized.
3634 for (const FieldDecl *FD : llvm::drop_begin(llvm::reverse(Fields)))
3635 UsedFieldIndex.push_back(FD->getFieldIndex());
3636
3637 for (auto UsedIter = UsedFieldIndex.begin(),
3638 UsedEnd = UsedFieldIndex.end(),
3639 OrigIter = InitFieldIndex.begin(),
3640 OrigEnd = InitFieldIndex.end();
3641 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
3642 if (*UsedIter < *OrigIter)
3643 return true;
3644 if (*UsedIter > *OrigIter)
3645 break;
3646 }
3647
3648 return false;
3649 }
3650
3651 void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly,
3652 bool AddressOf) {
3653 if (isa<EnumConstantDecl>(ME->getMemberDecl()))
3654 return;
3655
3656 // FieldME is the inner-most MemberExpr that is not an anonymous struct
3657 // or union.
3658 MemberExpr *FieldME = ME;
3659
3660 bool AllPODFields = FieldME->getType().isPODType(S.Context);
3661
3662 Expr *Base = ME;
3663 while (MemberExpr *SubME =
3664 dyn_cast<MemberExpr>(Base->IgnoreParenImpCasts())) {
3665
3666 if (isa<VarDecl>(SubME->getMemberDecl()))
3667 return;
3668
3669 if (FieldDecl *FD = dyn_cast<FieldDecl>(SubME->getMemberDecl()))
3670 if (!FD->isAnonymousStructOrUnion())
3671 FieldME = SubME;
3672
3673 if (!FieldME->getType().isPODType(S.Context))
3674 AllPODFields = false;
3675
3676 Base = SubME->getBase();
3677 }
3678
3679 if (!isa<CXXThisExpr>(Base->IgnoreParenImpCasts())) {
3680 Visit(Base);
3681 return;
3682 }
3683
3684 if (AddressOf && AllPODFields)
3685 return;
3686
3687 ValueDecl* FoundVD = FieldME->getMemberDecl();
3688
3689 if (ImplicitCastExpr *BaseCast = dyn_cast<ImplicitCastExpr>(Base)) {
3690 while (isa<ImplicitCastExpr>(BaseCast->getSubExpr())) {
3691 BaseCast = cast<ImplicitCastExpr>(BaseCast->getSubExpr());
3692 }
3693
3694 if (BaseCast->getCastKind() == CK_UncheckedDerivedToBase) {
3695 QualType T = BaseCast->getType();
3696 if (T->isPointerType() &&
3697 BaseClasses.count(T->getPointeeType())) {
3698 S.Diag(FieldME->getExprLoc(), diag::warn_base_class_is_uninit)
3699 << T->getPointeeType() << FoundVD;
3700 }
3701 }
3702 }
3703
3704 if (!Decls.count(FoundVD))
3705 return;
3706
3707 const bool IsReference = FoundVD->getType()->isReferenceType();
3708
3709 if (InitList && !AddressOf && FoundVD == InitListFieldDecl) {
3710 // Special checking for initializer lists.
3711 if (IsInitListMemberExprInitialized(ME, CheckReferenceOnly)) {
3712 return;
3713 }
3714 } else {
3715 // Prevent double warnings on use of unbounded references.
3716 if (CheckReferenceOnly && !IsReference)
3717 return;
3718 }
3719
3720 unsigned diag = IsReference
3721 ? diag::warn_reference_field_is_uninit
3722 : diag::warn_field_is_uninit;
3723 S.Diag(FieldME->getExprLoc(), diag) << FoundVD;
3724 if (Constructor)
3725 S.Diag(Constructor->getLocation(),
3726 diag::note_uninit_in_this_constructor)
3727 << (Constructor->isDefaultConstructor() && Constructor->isImplicit());
3728
3729 }
3730
3731 void HandleValue(Expr *E, bool AddressOf) {
3732 E = E->IgnoreParens();
3733
3734 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
3735 HandleMemberExpr(ME, false /*CheckReferenceOnly*/,
3736 AddressOf /*AddressOf*/);
3737 return;
3738 }
3739
3740 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
3741 Visit(CO->getCond());
3742 HandleValue(CO->getTrueExpr(), AddressOf);
3743 HandleValue(CO->getFalseExpr(), AddressOf);
3744 return;
3745 }
3746
3747 if (BinaryConditionalOperator *BCO =
3748 dyn_cast<BinaryConditionalOperator>(E)) {
3749 Visit(BCO->getCond());
3750 HandleValue(BCO->getFalseExpr(), AddressOf);
3751 return;
3752 }
3753
3754 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
3755 HandleValue(OVE->getSourceExpr(), AddressOf);
3756 return;
3757 }
3758
3759 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
3760 switch (BO->getOpcode()) {
3761 default:
3762 break;
3763 case(BO_PtrMemD):
3764 case(BO_PtrMemI):
3765 HandleValue(BO->getLHS(), AddressOf);
3766 Visit(BO->getRHS());
3767 return;
3768 case(BO_Comma):
3769 Visit(BO->getLHS());
3770 HandleValue(BO->getRHS(), AddressOf);
3771 return;
3772 }
3773 }
3774
3775 Visit(E);
3776 }
3777
3778 void CheckInitListExpr(InitListExpr *ILE) {
3779 InitFieldIndex.push_back(0);
3780 for (auto *Child : ILE->children()) {
3781 if (InitListExpr *SubList = dyn_cast<InitListExpr>(Child)) {
3782 CheckInitListExpr(SubList);
3783 } else {
3784 Visit(Child);
3785 }
3786 ++InitFieldIndex.back();
3787 }
3788 InitFieldIndex.pop_back();
3789 }
3790
3791 void CheckInitializer(Expr *E, const CXXConstructorDecl *FieldConstructor,
3792 FieldDecl *Field, const Type *BaseClass) {
3793 // Remove Decls that may have been initialized in the previous
3794 // initializer.
3795 for (ValueDecl* VD : DeclsToRemove)
3796 Decls.erase(VD);
3797 DeclsToRemove.clear();
3798
3799 Constructor = FieldConstructor;
3800 InitListExpr *ILE = dyn_cast<InitListExpr>(E);
3801
3802 if (ILE && Field) {
3803 InitList = true;
3804 InitListFieldDecl = Field;
3805 InitFieldIndex.clear();
3806 CheckInitListExpr(ILE);
3807 } else {
3808 InitList = false;
3809 Visit(E);
3810 }
3811
3812 if (Field)
3813 Decls.erase(Field);
3814 if (BaseClass)
3815 BaseClasses.erase(BaseClass->getCanonicalTypeInternal());
3816 }
3817
3818 void VisitMemberExpr(MemberExpr *ME) {
3819 // All uses of unbounded reference fields will warn.
3820 HandleMemberExpr(ME, true /*CheckReferenceOnly*/, false /*AddressOf*/);
3821 }
3822
3823 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
3824 if (E->getCastKind() == CK_LValueToRValue) {
3825 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3826 return;
3827 }
3828
3829 Inherited::VisitImplicitCastExpr(E);
3830 }
3831
3832 void VisitCXXConstructExpr(CXXConstructExpr *E) {
3833 if (E->getConstructor()->isCopyConstructor()) {
3834 Expr *ArgExpr = E->getArg(0);
3835 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
3836 if (ILE->getNumInits() == 1)
3837 ArgExpr = ILE->getInit(0);
3838 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
3839 if (ICE->getCastKind() == CK_NoOp)
3840 ArgExpr = ICE->getSubExpr();
3841 HandleValue(ArgExpr, false /*AddressOf*/);
3842 return;
3843 }
3844 Inherited::VisitCXXConstructExpr(E);
3845 }
3846
3847 void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
3848 Expr *Callee = E->getCallee();
3849 if (isa<MemberExpr>(Callee)) {
3850 HandleValue(Callee, false /*AddressOf*/);
3851 for (auto *Arg : E->arguments())
3852 Visit(Arg);
3853 return;
3854 }
3855
3856 Inherited::VisitCXXMemberCallExpr(E);
3857 }
3858
3859 void VisitCallExpr(CallExpr *E) {
3860 // Treat std::move as a use.
3861 if (E->isCallToStdMove()) {
3862 HandleValue(E->getArg(0), /*AddressOf=*/false);
3863 return;
3864 }
3865
3866 Inherited::VisitCallExpr(E);
3867 }
3868
3869 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
3870 Expr *Callee = E->getCallee();
3871
3872 if (isa<UnresolvedLookupExpr>(Callee))
3873 return Inherited::VisitCXXOperatorCallExpr(E);
3874
3875 Visit(Callee);
3876 for (auto *Arg : E->arguments())
3877 HandleValue(Arg->IgnoreParenImpCasts(), false /*AddressOf*/);
3878 }
3879
3880 void VisitBinaryOperator(BinaryOperator *E) {
3881 // If a field assignment is detected, remove the field from the
3882 // uninitiailized field set.
3883 if (E->getOpcode() == BO_Assign)
3884 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getLHS()))
3885 if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3886 if (!FD->getType()->isReferenceType())
3887 DeclsToRemove.push_back(FD);
3888
3889 if (E->isCompoundAssignmentOp()) {
3890 HandleValue(E->getLHS(), false /*AddressOf*/);
3891 Visit(E->getRHS());
3892 return;
3893 }
3894
3895 Inherited::VisitBinaryOperator(E);
3896 }
3897
3898 void VisitUnaryOperator(UnaryOperator *E) {
3899 if (E->isIncrementDecrementOp()) {
3900 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3901 return;
3902 }
3903 if (E->getOpcode() == UO_AddrOf) {
3904 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getSubExpr())) {
3905 HandleValue(ME->getBase(), true /*AddressOf*/);
3906 return;
3907 }
3908 }
3909
3910 Inherited::VisitUnaryOperator(E);
3911 }
3912 };
3913
3914 // Diagnose value-uses of fields to initialize themselves, e.g.
3915 // foo(foo)
3916 // where foo is not also a parameter to the constructor.
3917 // Also diagnose across field uninitialized use such as
3918 // x(y), y(x)
3919 // TODO: implement -Wuninitialized and fold this into that framework.
3920 static void DiagnoseUninitializedFields(
3921 Sema &SemaRef, const CXXConstructorDecl *Constructor) {
3922
3923 if (SemaRef.getDiagnostics().isIgnored(diag::warn_field_is_uninit,
3924 Constructor->getLocation())) {
3925 return;
3926 }
3927
3928 if (Constructor->isInvalidDecl())
3929 return;
3930
3931 const CXXRecordDecl *RD = Constructor->getParent();
3932
3933 if (RD->isDependentContext())
3934 return;
3935
3936 // Holds fields that are uninitialized.
3937 llvm::SmallPtrSet<ValueDecl*, 4> UninitializedFields;
3938
3939 // At the beginning, all fields are uninitialized.
3940 for (auto *I : RD->decls()) {
3941 if (auto *FD = dyn_cast<FieldDecl>(I)) {
3942 UninitializedFields.insert(FD);
3943 } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(I)) {
3944 UninitializedFields.insert(IFD->getAnonField());
3945 }
3946 }
3947
3948 llvm::SmallPtrSet<QualType, 4> UninitializedBaseClasses;
3949 for (auto I : RD->bases())
3950 UninitializedBaseClasses.insert(I.getType().getCanonicalType());
3951
3952 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3953 return;
3954
3955 UninitializedFieldVisitor UninitializedChecker(SemaRef,
3956 UninitializedFields,
3957 UninitializedBaseClasses);
3958
3959 for (const auto *FieldInit : Constructor->inits()) {
3960 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3961 break;
3962
3963 Expr *InitExpr = FieldInit->getInit();
3964 if (!InitExpr)
3965 continue;
3966
3967 if (CXXDefaultInitExpr *Default =
3968 dyn_cast<CXXDefaultInitExpr>(InitExpr)) {
3969 InitExpr = Default->getExpr();
3970 if (!InitExpr)
3971 continue;
3972 // In class initializers will point to the constructor.
3973 UninitializedChecker.CheckInitializer(InitExpr, Constructor,
3974 FieldInit->getAnyMember(),
3975 FieldInit->getBaseClass());
3976 } else {
3977 UninitializedChecker.CheckInitializer(InitExpr, nullptr,
3978 FieldInit->getAnyMember(),
3979 FieldInit->getBaseClass());
3980 }
3981 }
3982 }
3983} // namespace
3984
3985/// Enter a new C++ default initializer scope. After calling this, the
3986/// caller must call \ref ActOnFinishCXXInClassMemberInitializer, even if
3987/// parsing or instantiating the initializer failed.
3988void Sema::ActOnStartCXXInClassMemberInitializer() {
3989 // Create a synthetic function scope to represent the call to the constructor
3990 // that notionally surrounds a use of this initializer.
3991 PushFunctionScope();
3992}
3993
3994void Sema::ActOnStartTrailingRequiresClause(Scope *S, Declarator &D) {
3995 if (!D.isFunctionDeclarator())
3996 return;
3997 auto &FTI = D.getFunctionTypeInfo();
3998 if (!FTI.Params)
3999 return;
4000 for (auto &Param : ArrayRef<DeclaratorChunk::ParamInfo>(FTI.Params,
4001 FTI.NumParams)) {
4002 auto *ParamDecl = cast<NamedDecl>(Param.Param);
4003 if (ParamDecl->getDeclName())
4004 PushOnScopeChains(ParamDecl, S, /*AddToContext=*/false);
4005 }
4006}
4007
4008ExprResult Sema::ActOnFinishTrailingRequiresClause(ExprResult ConstraintExpr) {
4009 return ActOnRequiresClause(ConstraintExpr);
4010}
4011
4012ExprResult Sema::ActOnRequiresClause(ExprResult ConstraintExpr) {
4013 if (ConstraintExpr.isInvalid())
4014 return ExprError();
4015
4016 ConstraintExpr = CorrectDelayedTyposInExpr(ConstraintExpr);
4017 if (ConstraintExpr.isInvalid())
4018 return ExprError();
4019
4020 if (DiagnoseUnexpandedParameterPack(ConstraintExpr.get(),
4021 UPPC_RequiresClause))
4022 return ExprError();
4023
4024 return ConstraintExpr;
4025}
4026
4027/// This is invoked after parsing an in-class initializer for a
4028/// non-static C++ class member, and after instantiating an in-class initializer
4029/// in a class template. Such actions are deferred until the class is complete.
4030void Sema::ActOnFinishCXXInClassMemberInitializer(Decl *D,
4031 SourceLocation InitLoc,
4032 Expr *InitExpr) {
4033 // Pop the notional constructor scope we created earlier.
4034 PopFunctionScopeInfo(nullptr, D);
4035
4036 FieldDecl *FD = dyn_cast<FieldDecl>(D);
4037 assert((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) &&(static_cast <bool> ((isa<MSPropertyDecl>(D) || FD
->getInClassInitStyle() != ICIS_NoInit) && "must set init style when field is created"
) ? void (0) : __assert_fail ("(isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) && \"must set init style when field is created\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4038, __extension__ __PRETTY_FUNCTION__
))
4038 "must set init style when field is created")(static_cast <bool> ((isa<MSPropertyDecl>(D) || FD
->getInClassInitStyle() != ICIS_NoInit) && "must set init style when field is created"
) ? void (0) : __assert_fail ("(isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) && \"must set init style when field is created\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4038, __extension__ __PRETTY_FUNCTION__
))
;
4039
4040 if (!InitExpr) {
4041 D->setInvalidDecl();
4042 if (FD)
4043 FD->removeInClassInitializer();
4044 return;
4045 }
4046
4047 if (DiagnoseUnexpandedParameterPack(InitExpr, UPPC_Initializer)) {
4048 FD->setInvalidDecl();
4049 FD->removeInClassInitializer();
4050 return;
4051 }
4052
4053 ExprResult Init = InitExpr;
4054 if (!FD->getType()->isDependentType() && !InitExpr->isTypeDependent()) {
4055 InitializedEntity Entity =
4056 InitializedEntity::InitializeMemberFromDefaultMemberInitializer(FD);
4057 InitializationKind Kind =
4058 FD->getInClassInitStyle() == ICIS_ListInit
4059 ? InitializationKind::CreateDirectList(InitExpr->getBeginLoc(),
4060 InitExpr->getBeginLoc(),
4061 InitExpr->getEndLoc())
4062 : InitializationKind::CreateCopy(InitExpr->getBeginLoc(), InitLoc);
4063 InitializationSequence Seq(*this, Entity, Kind, InitExpr);
4064 Init = Seq.Perform(*this, Entity, Kind, InitExpr);
4065 if (Init.isInvalid()) {
4066 FD->setInvalidDecl();
4067 return;
4068 }
4069 }
4070
4071 // C++11 [class.base.init]p7:
4072 // The initialization of each base and member constitutes a
4073 // full-expression.
4074 Init = ActOnFinishFullExpr(Init.get(), InitLoc, /*DiscardedValue*/ false);
4075 if (Init.isInvalid()) {
4076 FD->setInvalidDecl();
4077 return;
4078 }
4079
4080 InitExpr = Init.get();
4081
4082 FD->setInClassInitializer(InitExpr);
4083}
4084
4085/// Find the direct and/or virtual base specifiers that
4086/// correspond to the given base type, for use in base initialization
4087/// within a constructor.
4088static bool FindBaseInitializer(Sema &SemaRef,
4089 CXXRecordDecl *ClassDecl,
4090 QualType BaseType,
4091 const CXXBaseSpecifier *&DirectBaseSpec,
4092 const CXXBaseSpecifier *&VirtualBaseSpec) {
4093 // First, check for a direct base class.
4094 DirectBaseSpec = nullptr;
4095 for (const auto &Base : ClassDecl->bases()) {
4096 if (SemaRef.Context.hasSameUnqualifiedType(BaseType, Base.getType())) {
4097 // We found a direct base of this type. That's what we're
4098 // initializing.
4099 DirectBaseSpec = &Base;
4100 break;
4101 }
4102 }
4103
4104 // Check for a virtual base class.
4105 // FIXME: We might be able to short-circuit this if we know in advance that
4106 // there are no virtual bases.
4107 VirtualBaseSpec = nullptr;
4108 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) {
4109 // We haven't found a base yet; search the class hierarchy for a
4110 // virtual base class.
4111 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
4112 /*DetectVirtual=*/false);
4113 if (SemaRef.IsDerivedFrom(ClassDecl->getLocation(),
4114 SemaRef.Context.getTypeDeclType(ClassDecl),
4115 BaseType, Paths)) {
4116 for (CXXBasePaths::paths_iterator Path = Paths.begin();
4117 Path != Paths.end(); ++Path) {
4118 if (Path->back().Base->isVirtual()) {
4119 VirtualBaseSpec = Path->back().Base;
4120 break;
4121 }
4122 }
4123 }
4124 }
4125
4126 return DirectBaseSpec || VirtualBaseSpec;
4127}
4128
4129/// Handle a C++ member initializer using braced-init-list syntax.
4130MemInitResult
4131Sema::ActOnMemInitializer(Decl *ConstructorD,
4132 Scope *S,
4133 CXXScopeSpec &SS,
4134 IdentifierInfo *MemberOrBase,
4135 ParsedType TemplateTypeTy,
4136 const DeclSpec &DS,
4137 SourceLocation IdLoc,
4138 Expr *InitList,
4139 SourceLocation EllipsisLoc) {
4140 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
4141 DS, IdLoc, InitList,
4142 EllipsisLoc);
4143}
4144
4145/// Handle a C++ member initializer using parentheses syntax.
4146MemInitResult
4147Sema::ActOnMemInitializer(Decl *ConstructorD,
4148 Scope *S,
4149 CXXScopeSpec &SS,
4150 IdentifierInfo *MemberOrBase,
4151 ParsedType TemplateTypeTy,
4152 const DeclSpec &DS,
4153 SourceLocation IdLoc,
4154 SourceLocation LParenLoc,
4155 ArrayRef<Expr *> Args,
4156 SourceLocation RParenLoc,
4157 SourceLocation EllipsisLoc) {
4158 Expr *List = ParenListExpr::Create(Context, LParenLoc, Args, RParenLoc);
4159 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
4160 DS, IdLoc, List, EllipsisLoc);
4161}
4162
4163namespace {
4164
4165// Callback to only accept typo corrections that can be a valid C++ member
4166// initializer: either a non-static field member or a base class.
4167class MemInitializerValidatorCCC final : public CorrectionCandidateCallback {
4168public:
4169 explicit MemInitializerValidatorCCC(CXXRecordDecl *ClassDecl)
4170 : ClassDecl(ClassDecl) {}
4171
4172 bool ValidateCandidate(const TypoCorrection &candidate) override {
4173 if (NamedDecl *ND = candidate.getCorrectionDecl()) {
4174 if (FieldDecl *Member = dyn_cast<FieldDecl>(ND))
4175 return Member->getDeclContext()->getRedeclContext()->Equals(ClassDecl);
4176 return isa<TypeDecl>(ND);
4177 }
4178 return false;
4179 }
4180
4181 std::unique_ptr<CorrectionCandidateCallback> clone() override {
4182 return std::make_unique<MemInitializerValidatorCCC>(*this);
4183 }
4184
4185private:
4186 CXXRecordDecl *ClassDecl;
4187};
4188
4189}
4190
4191ValueDecl *Sema::tryLookupCtorInitMemberDecl(CXXRecordDecl *ClassDecl,
4192 CXXScopeSpec &SS,
4193 ParsedType TemplateTypeTy,
4194 IdentifierInfo *MemberOrBase) {
4195 if (SS.getScopeRep() || TemplateTypeTy)
4196 return nullptr;
4197 for (auto *D : ClassDecl->lookup(MemberOrBase))
4198 if (isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D))
4199 return cast<ValueDecl>(D);
4200 return nullptr;
4201}
4202
4203/// Handle a C++ member initializer.
4204MemInitResult
4205Sema::BuildMemInitializer(Decl *ConstructorD,
4206 Scope *S,
4207 CXXScopeSpec &SS,
4208 IdentifierInfo *MemberOrBase,
4209 ParsedType TemplateTypeTy,
4210 const DeclSpec &DS,
4211 SourceLocation IdLoc,
4212 Expr *Init,
4213 SourceLocation EllipsisLoc) {
4214 ExprResult Res = CorrectDelayedTyposInExpr(Init, /*InitDecl=*/nullptr,
4215 /*RecoverUncorrectedTypos=*/true);
4216 if (!Res.isUsable())
4217 return true;
4218 Init = Res.get();
4219
4220 if (!ConstructorD)
4221 return true;
4222
4223 AdjustDeclIfTemplate(ConstructorD);
4224
4225 CXXConstructorDecl *Constructor
4226 = dyn_cast<CXXConstructorDecl>(ConstructorD);
4227 if (!Constructor) {
4228 // The user wrote a constructor initializer on a function that is
4229 // not a C++ constructor. Ignore the error for now, because we may
4230 // have more member initializers coming; we'll diagnose it just
4231 // once in ActOnMemInitializers.
4232 return true;
4233 }
4234
4235 CXXRecordDecl *ClassDecl = Constructor->getParent();
4236
4237 // C++ [class.base.init]p2:
4238 // Names in a mem-initializer-id are looked up in the scope of the
4239 // constructor's class and, if not found in that scope, are looked
4240 // up in the scope containing the constructor's definition.
4241 // [Note: if the constructor's class contains a member with the
4242 // same name as a direct or virtual base class of the class, a
4243 // mem-initializer-id naming the member or base class and composed
4244 // of a single identifier refers to the class member. A
4245 // mem-initializer-id for the hidden base class may be specified
4246 // using a qualified name. ]
4247
4248 // Look for a member, first.
4249 if (ValueDecl *Member = tryLookupCtorInitMemberDecl(
4250 ClassDecl, SS, TemplateTypeTy, MemberOrBase)) {
4251 if (EllipsisLoc.isValid())
4252 Diag(EllipsisLoc, diag::err_pack_expansion_member_init)
4253 << MemberOrBase
4254 << SourceRange(IdLoc, Init->getSourceRange().getEnd());
4255
4256 return BuildMemberInitializer(Member, Init, IdLoc);
4257 }
4258 // It didn't name a member, so see if it names a class.
4259 QualType BaseType;
4260 TypeSourceInfo *TInfo = nullptr;
4261
4262 if (TemplateTypeTy) {
4263 BaseType = GetTypeFromParser(TemplateTypeTy, &TInfo);
4264 if (BaseType.isNull())
4265 return true;
4266 } else if (DS.getTypeSpecType() == TST_decltype) {
4267 BaseType = BuildDecltypeType(DS.getRepAsExpr());
4268 } else if (DS.getTypeSpecType() == TST_decltype_auto) {
4269 Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
4270 return true;
4271 } else {
4272 LookupResult R(*this, MemberOrBase, IdLoc, LookupOrdinaryName);
4273 LookupParsedName(R, S, &SS);
4274
4275 TypeDecl *TyD = R.getAsSingle<TypeDecl>();
4276 if (!TyD) {
4277 if (R.isAmbiguous()) return true;
4278
4279 // We don't want access-control diagnostics here.
4280 R.suppressDiagnostics();
4281
4282 if (SS.isSet() && isDependentScopeSpecifier(SS)) {
4283 bool NotUnknownSpecialization = false;
4284 DeclContext *DC = computeDeclContext(SS, false);
4285 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(DC))
4286 NotUnknownSpecialization = !Record->hasAnyDependentBases();
4287
4288 if (!NotUnknownSpecialization) {
4289 // When the scope specifier can refer to a member of an unknown
4290 // specialization, we take it as a type name.
4291 BaseType = CheckTypenameType(ETK_None, SourceLocation(),
4292 SS.getWithLocInContext(Context),
4293 *MemberOrBase, IdLoc);
4294 if (BaseType.isNull())
4295 return true;
4296
4297 TInfo = Context.CreateTypeSourceInfo(BaseType);
4298 DependentNameTypeLoc TL =
4299 TInfo->getTypeLoc().castAs<DependentNameTypeLoc>();
4300 if (!TL.isNull()) {
4301 TL.setNameLoc(IdLoc);
4302 TL.setElaboratedKeywordLoc(SourceLocation());
4303 TL.setQualifierLoc(SS.getWithLocInContext(Context));
4304 }
4305
4306 R.clear();
4307 R.setLookupName(MemberOrBase);
4308 }
4309 }
4310
4311 if (getLangOpts().MSVCCompat && !getLangOpts().CPlusPlus20) {
4312 if (auto UnqualifiedBase = R.getAsSingle<ClassTemplateDecl>()) {
4313 auto *TempSpec = cast<TemplateSpecializationType>(
4314 UnqualifiedBase->getInjectedClassNameSpecialization());
4315 TemplateName TN = TempSpec->getTemplateName();
4316 for (auto const &Base : ClassDecl->bases()) {
4317 auto BaseTemplate =
4318 Base.getType()->getAs<TemplateSpecializationType>();
4319 if (BaseTemplate && Context.hasSameTemplateName(
4320 BaseTemplate->getTemplateName(), TN)) {
4321 Diag(IdLoc, diag::ext_unqualified_base_class)
4322 << SourceRange(IdLoc, Init->getSourceRange().getEnd());
4323 BaseType = Base.getType();
4324 break;
4325 }
4326 }
4327 }
4328 }
4329
4330 // If no results were found, try to correct typos.
4331 TypoCorrection Corr;
4332 MemInitializerValidatorCCC CCC(ClassDecl);
4333 if (R.empty() && BaseType.isNull() &&
4334 (Corr = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
4335 CCC, CTK_ErrorRecovery, ClassDecl))) {
4336 if (FieldDecl *Member = Corr.getCorrectionDeclAs<FieldDecl>()) {
4337 // We have found a non-static data member with a similar
4338 // name to what was typed; complain and initialize that
4339 // member.
4340 diagnoseTypo(Corr,
4341 PDiag(diag::err_mem_init_not_member_or_class_suggest)
4342 << MemberOrBase << true);
4343 return BuildMemberInitializer(Member, Init, IdLoc);
4344 } else if (TypeDecl *Type = Corr.getCorrectionDeclAs<TypeDecl>()) {
4345 const CXXBaseSpecifier *DirectBaseSpec;
4346 const CXXBaseSpecifier *VirtualBaseSpec;
4347 if (FindBaseInitializer(*this, ClassDecl,
4348 Context.getTypeDeclType(Type),
4349 DirectBaseSpec, VirtualBaseSpec)) {
4350 // We have found a direct or virtual base class with a
4351 // similar name to what was typed; complain and initialize
4352 // that base class.
4353 diagnoseTypo(Corr,
4354 PDiag(diag::err_mem_init_not_member_or_class_suggest)
4355 << MemberOrBase << false,
4356 PDiag() /*Suppress note, we provide our own.*/);
4357
4358 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec ? DirectBaseSpec
4359 : VirtualBaseSpec;
4360 Diag(BaseSpec->getBeginLoc(), diag::note_base_class_specified_here)
4361 << BaseSpec->getType() << BaseSpec->getSourceRange();
4362
4363 TyD = Type;
4364 }
4365 }
4366 }
4367
4368 if (!TyD && BaseType.isNull()) {
4369 Diag(IdLoc, diag::err_mem_init_not_member_or_class)
4370 << MemberOrBase << SourceRange(IdLoc,Init->getSourceRange().getEnd());
4371 return true;
4372 }
4373 }
4374
4375 if (BaseType.isNull()) {
4376 BaseType = getElaboratedType(ETK_None, SS, Context.getTypeDeclType(TyD));
4377 MarkAnyDeclReferenced(TyD->getLocation(), TyD, /*OdrUse=*/false);
4378 TInfo = Context.CreateTypeSourceInfo(BaseType);
4379 ElaboratedTypeLoc TL = TInfo->getTypeLoc().castAs<ElaboratedTypeLoc>();
4380 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
4381 TL.setElaboratedKeywordLoc(SourceLocation());
4382 TL.setQualifierLoc(SS.getWithLocInContext(Context));
4383 }
4384 }
4385
4386 if (!TInfo)
4387 TInfo = Context.getTrivialTypeSourceInfo(BaseType, IdLoc);
4388
4389 return BuildBaseInitializer(BaseType, TInfo, Init, ClassDecl, EllipsisLoc);
4390}
4391
4392MemInitResult
4393Sema::BuildMemberInitializer(ValueDecl *Member, Expr *Init,
4394 SourceLocation IdLoc) {
4395 FieldDecl *DirectMember = dyn_cast<FieldDecl>(Member);
4396 IndirectFieldDecl *IndirectMember = dyn_cast<IndirectFieldDecl>(Member);
4397 assert((DirectMember || IndirectMember) &&(static_cast <bool> ((DirectMember || IndirectMember) &&
"Member must be a FieldDecl or IndirectFieldDecl") ? void (0
) : __assert_fail ("(DirectMember || IndirectMember) && \"Member must be a FieldDecl or IndirectFieldDecl\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4398, __extension__ __PRETTY_FUNCTION__
))
4398 "Member must be a FieldDecl or IndirectFieldDecl")(static_cast <bool> ((DirectMember || IndirectMember) &&
"Member must be a FieldDecl or IndirectFieldDecl") ? void (0
) : __assert_fail ("(DirectMember || IndirectMember) && \"Member must be a FieldDecl or IndirectFieldDecl\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4398, __extension__ __PRETTY_FUNCTION__
))
;
4399
4400 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
4401 return true;
4402
4403 if (Member->isInvalidDecl())
4404 return true;
4405
4406 MultiExprArg Args;
4407 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4408 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4409 } else if (InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
4410 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
4411 } else {
4412 // Template instantiation doesn't reconstruct ParenListExprs for us.
4413 Args = Init;
4414 }
4415
4416 SourceRange InitRange = Init->getSourceRange();
4417
4418 if (Member->getType()->isDependentType() || Init->isTypeDependent()) {
4419 // Can't check initialization for a member of dependent type or when
4420 // any of the arguments are type-dependent expressions.
4421 DiscardCleanupsInEvaluationContext();
4422 } else {
4423 bool InitList = false;
4424 if (isa<InitListExpr>(Init)) {
4425 InitList = true;
4426 Args = Init;
4427 }
4428
4429 // Initialize the member.
4430 InitializedEntity MemberEntity =
4431 DirectMember ? InitializedEntity::InitializeMember(DirectMember, nullptr)
4432 : InitializedEntity::InitializeMember(IndirectMember,
4433 nullptr);
4434 InitializationKind Kind =
4435 InitList ? InitializationKind::CreateDirectList(
4436 IdLoc, Init->getBeginLoc(), Init->getEndLoc())
4437 : InitializationKind::CreateDirect(IdLoc, InitRange.getBegin(),
4438 InitRange.getEnd());
4439
4440 InitializationSequence InitSeq(*this, MemberEntity, Kind, Args);
4441 ExprResult MemberInit = InitSeq.Perform(*this, MemberEntity, Kind, Args,
4442 nullptr);
4443 if (!MemberInit.isInvalid()) {
4444 // C++11 [class.base.init]p7:
4445 // The initialization of each base and member constitutes a
4446 // full-expression.
4447 MemberInit = ActOnFinishFullExpr(MemberInit.get(), InitRange.getBegin(),
4448 /*DiscardedValue*/ false);
4449 }
4450
4451 if (MemberInit.isInvalid()) {
4452 // Args were sensible expressions but we couldn't initialize the member
4453 // from them. Preserve them in a RecoveryExpr instead.
4454 Init = CreateRecoveryExpr(InitRange.getBegin(), InitRange.getEnd(), Args,
4455 Member->getType())
4456 .get();
4457 if (!Init)
4458 return true;
4459 } else {
4460 Init = MemberInit.get();
4461 }
4462 }
4463
4464 if (DirectMember) {
4465 return new (Context) CXXCtorInitializer(Context, DirectMember, IdLoc,
4466 InitRange.getBegin(), Init,
4467 InitRange.getEnd());
4468 } else {
4469 return new (Context) CXXCtorInitializer(Context, IndirectMember, IdLoc,
4470 InitRange.getBegin(), Init,
4471 InitRange.getEnd());
4472 }
4473}
4474
4475MemInitResult
4476Sema::BuildDelegatingInitializer(TypeSourceInfo *TInfo, Expr *Init,
4477 CXXRecordDecl *ClassDecl) {
4478 SourceLocation NameLoc = TInfo->getTypeLoc().getSourceRange().getBegin();
4479 if (!LangOpts.CPlusPlus11)
4480 return Diag(NameLoc, diag::err_delegating_ctor)
4481 << TInfo->getTypeLoc().getSourceRange();
4482 Diag(NameLoc, diag::warn_cxx98_compat_delegating_ctor);
4483
4484 bool InitList = true;
4485 MultiExprArg Args = Init;
4486 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4487 InitList = false;
4488 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4489 }
4490
4491 SourceRange InitRange = Init->getSourceRange();
4492 // Initialize the object.
4493 InitializedEntity DelegationEntity = InitializedEntity::InitializeDelegation(
4494 QualType(ClassDecl->getTypeForDecl(), 0));
4495 InitializationKind Kind =
4496 InitList ? InitializationKind::CreateDirectList(
4497 NameLoc, Init->getBeginLoc(), Init->getEndLoc())
4498 : InitializationKind::CreateDirect(NameLoc, InitRange.getBegin(),
4499 InitRange.getEnd());
4500 InitializationSequence InitSeq(*this, DelegationEntity, Kind, Args);
4501 ExprResult DelegationInit = InitSeq.Perform(*this, DelegationEntity, Kind,
4502 Args, nullptr);
4503 if (!DelegationInit.isInvalid()) {
4504 assert((DelegationInit.get()->containsErrors() ||(static_cast <bool> ((DelegationInit.get()->containsErrors
() || cast<CXXConstructExpr>(DelegationInit.get())->
getConstructor()) && "Delegating constructor with no target?"
) ? void (0) : __assert_fail ("(DelegationInit.get()->containsErrors() || cast<CXXConstructExpr>(DelegationInit.get())->getConstructor()) && \"Delegating constructor with no target?\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4506, __extension__ __PRETTY_FUNCTION__
))
4505 cast<CXXConstructExpr>(DelegationInit.get())->getConstructor()) &&(static_cast <bool> ((DelegationInit.get()->containsErrors
() || cast<CXXConstructExpr>(DelegationInit.get())->
getConstructor()) && "Delegating constructor with no target?"
) ? void (0) : __assert_fail ("(DelegationInit.get()->containsErrors() || cast<CXXConstructExpr>(DelegationInit.get())->getConstructor()) && \"Delegating constructor with no target?\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4506, __extension__ __PRETTY_FUNCTION__
))
4506 "Delegating constructor with no target?")(static_cast <bool> ((DelegationInit.get()->containsErrors
() || cast<CXXConstructExpr>(DelegationInit.get())->
getConstructor()) && "Delegating constructor with no target?"
) ? void (0) : __assert_fail ("(DelegationInit.get()->containsErrors() || cast<CXXConstructExpr>(DelegationInit.get())->getConstructor()) && \"Delegating constructor with no target?\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4506, __extension__ __PRETTY_FUNCTION__
))
;
4507
4508 // C++11 [class.base.init]p7:
4509 // The initialization of each base and member constitutes a
4510 // full-expression.
4511 DelegationInit = ActOnFinishFullExpr(
4512 DelegationInit.get(), InitRange.getBegin(), /*DiscardedValue*/ false);
4513 }
4514
4515 if (DelegationInit.isInvalid()) {
4516 DelegationInit =
4517 CreateRecoveryExpr(InitRange.getBegin(), InitRange.getEnd(), Args,
4518 QualType(ClassDecl->getTypeForDecl(), 0));
4519 if (DelegationInit.isInvalid())
4520 return true;
4521 } else {
4522 // If we are in a dependent context, template instantiation will
4523 // perform this type-checking again. Just save the arguments that we
4524 // received in a ParenListExpr.
4525 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4526 // of the information that we have about the base
4527 // initializer. However, deconstructing the ASTs is a dicey process,
4528 // and this approach is far more likely to get the corner cases right.
4529 if (CurContext->isDependentContext())
4530 DelegationInit = Init;
4531 }
4532
4533 return new (Context) CXXCtorInitializer(Context, TInfo, InitRange.getBegin(),
4534 DelegationInit.getAs<Expr>(),
4535 InitRange.getEnd());
4536}
4537
4538MemInitResult
4539Sema::BuildBaseInitializer(QualType BaseType, TypeSourceInfo *BaseTInfo,
4540 Expr *Init, CXXRecordDecl *ClassDecl,
4541 SourceLocation EllipsisLoc) {
4542 SourceLocation BaseLoc = BaseTInfo->getTypeLoc().getBeginLoc();
4543
4544 if (!BaseType->isDependentType() && !BaseType->isRecordType())
4545 return Diag(BaseLoc, diag::err_base_init_does_not_name_class)
4546 << BaseType << BaseTInfo->getTypeLoc().getSourceRange();
4547
4548 // C++ [class.base.init]p2:
4549 // [...] Unless the mem-initializer-id names a nonstatic data
4550 // member of the constructor's class or a direct or virtual base
4551 // of that class, the mem-initializer is ill-formed. A
4552 // mem-initializer-list can initialize a base class using any
4553 // name that denotes that base class type.
4554
4555 // We can store the initializers in "as-written" form and delay analysis until
4556 // instantiation if the constructor is dependent. But not for dependent
4557 // (broken) code in a non-template! SetCtorInitializers does not expect this.
4558 bool Dependent = CurContext->isDependentContext() &&
4559 (BaseType->isDependentType() || Init->isTypeDependent());
4560
4561 SourceRange InitRange = Init->getSourceRange();
4562 if (EllipsisLoc.isValid()) {
4563 // This is a pack expansion.
4564 if (!BaseType->containsUnexpandedParameterPack()) {
4565 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
4566 << SourceRange(BaseLoc, InitRange.getEnd());
4567
4568 EllipsisLoc = SourceLocation();
4569 }
4570 } else {
4571 // Check for any unexpanded parameter packs.
4572 if (DiagnoseUnexpandedParameterPack(BaseLoc, BaseTInfo, UPPC_Initializer))
4573 return true;
4574
4575 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
4576 return true;
4577 }
4578
4579 // Check for direct and virtual base classes.
4580 const CXXBaseSpecifier *DirectBaseSpec = nullptr;
4581 const CXXBaseSpecifier *VirtualBaseSpec = nullptr;
4582 if (!Dependent) {
4583 if (Context.hasSameUnqualifiedType(QualType(ClassDecl->getTypeForDecl(),0),
4584 BaseType))
4585 return BuildDelegatingInitializer(BaseTInfo, Init, ClassDecl);
4586
4587 FindBaseInitializer(*this, ClassDecl, BaseType, DirectBaseSpec,
4588 VirtualBaseSpec);
4589
4590 // C++ [base.class.init]p2:
4591 // Unless the mem-initializer-id names a nonstatic data member of the
4592 // constructor's class or a direct or virtual base of that class, the
4593 // mem-initializer is ill-formed.
4594 if (!DirectBaseSpec && !VirtualBaseSpec) {
4595 // If the class has any dependent bases, then it's possible that
4596 // one of those types will resolve to the same type as
4597 // BaseType. Therefore, just treat this as a dependent base
4598 // class initialization. FIXME: Should we try to check the
4599 // initialization anyway? It seems odd.
4600 if (ClassDecl->hasAnyDependentBases())
4601 Dependent = true;
4602 else
4603 return Diag(BaseLoc, diag::err_not_direct_base_or_virtual)
4604 << BaseType << Context.getTypeDeclType(ClassDecl)
4605 << BaseTInfo->getTypeLoc().getSourceRange();
4606 }
4607 }
4608
4609 if (Dependent) {
4610 DiscardCleanupsInEvaluationContext();
4611
4612 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4613 /*IsVirtual=*/false,
4614 InitRange.getBegin(), Init,
4615 InitRange.getEnd(), EllipsisLoc);
4616 }
4617
4618 // C++ [base.class.init]p2:
4619 // If a mem-initializer-id is ambiguous because it designates both
4620 // a direct non-virtual base class and an inherited virtual base
4621 // class, the mem-initializer is ill-formed.
4622 if (DirectBaseSpec && VirtualBaseSpec)
4623 return Diag(BaseLoc, diag::err_base_init_direct_and_virtual)
4624 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
4625
4626 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec;
4627 if (!BaseSpec)
4628 BaseSpec = VirtualBaseSpec;
4629
4630 // Initialize the base.
4631 bool InitList = true;
4632 MultiExprArg Args = Init;
4633 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4634 InitList = false;
4635 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4636 }
4637
4638 InitializedEntity BaseEntity =
4639 InitializedEntity::InitializeBase(Context, BaseSpec, VirtualBaseSpec);
4640 InitializationKind Kind =
4641 InitList ? InitializationKind::CreateDirectList(BaseLoc)
4642 : InitializationKind::CreateDirect(BaseLoc, InitRange.getBegin(),
4643 InitRange.getEnd());
4644 InitializationSequence InitSeq(*this, BaseEntity, Kind, Args);
4645 ExprResult BaseInit = InitSeq.Perform(*this, BaseEntity, Kind, Args, nullptr);
4646 if (!BaseInit.isInvalid()) {
4647 // C++11 [class.base.init]p7:
4648 // The initialization of each base and member constitutes a
4649 // full-expression.
4650 BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin(),
4651 /*DiscardedValue*/ false);
4652 }
4653
4654 if (BaseInit.isInvalid()) {
4655 BaseInit = CreateRecoveryExpr(InitRange.getBegin(), InitRange.getEnd(),
4656 Args, BaseType);
4657 if (BaseInit.isInvalid())
4658 return true;
4659 } else {
4660 // If we are in a dependent context, template instantiation will
4661 // perform this type-checking again. Just save the arguments that we
4662 // received in a ParenListExpr.
4663 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4664 // of the information that we have about the base
4665 // initializer. However, deconstructing the ASTs is a dicey process,
4666 // and this approach is far more likely to get the corner cases right.
4667 if (CurContext->isDependentContext())
4668 BaseInit = Init;
4669 }
4670
4671 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4672 BaseSpec->isVirtual(),
4673 InitRange.getBegin(),
4674 BaseInit.getAs<Expr>(),
4675 InitRange.getEnd(), EllipsisLoc);
4676}
4677
4678// Create a static_cast\<T&&>(expr).
4679static Expr *CastForMoving(Sema &SemaRef, Expr *E, QualType T = QualType()) {
4680 if (T.isNull()) T = E->getType();
4681 QualType TargetType = SemaRef.BuildReferenceType(
4682 T, /*SpelledAsLValue*/false, SourceLocation(), DeclarationName());
4683 SourceLocation ExprLoc = E->getBeginLoc();
4684 TypeSourceInfo *TargetLoc = SemaRef.Context.getTrivialTypeSourceInfo(
4685 TargetType, ExprLoc);
4686
4687 return SemaRef.BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E,
4688 SourceRange(ExprLoc, ExprLoc),
4689 E->getSourceRange()).get();
4690}
4691
4692/// ImplicitInitializerKind - How an implicit base or member initializer should
4693/// initialize its base or member.
4694enum ImplicitInitializerKind {
4695 IIK_Default,
4696 IIK_Copy,
4697 IIK_Move,
4698 IIK_Inherit
4699};
4700
4701static bool
4702BuildImplicitBaseInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4703 ImplicitInitializerKind ImplicitInitKind,
4704 CXXBaseSpecifier *BaseSpec,
4705 bool IsInheritedVirtualBase,
4706 CXXCtorInitializer *&CXXBaseInit) {
4707 InitializedEntity InitEntity
4708 = InitializedEntity::InitializeBase(SemaRef.Context, BaseSpec,
4709 IsInheritedVirtualBase);
4710
4711 ExprResult BaseInit;
4712
4713 switch (ImplicitInitKind) {
4714 case IIK_Inherit:
4715 case IIK_Default: {
4716 InitializationKind InitKind
4717 = InitializationKind::CreateDefault(Constructor->getLocation());
4718 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4719 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4720 break;
4721 }
4722
4723 case IIK_Move:
4724 case IIK_Copy: {
4725 bool Moving = ImplicitInitKind == IIK_Move;
4726 ParmVarDecl *Param = Constructor->getParamDecl(0);
4727 QualType ParamType = Param->getType().getNonReferenceType();
4728
4729 Expr *CopyCtorArg =
4730 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4731 SourceLocation(), Param, false,
4732 Constructor->getLocation(), ParamType,
4733 VK_LValue, nullptr);
4734
4735 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(CopyCtorArg));
4736
4737 // Cast to the base class to avoid ambiguities.
4738 QualType ArgTy =
4739 SemaRef.Context.getQualifiedType(BaseSpec->getType().getUnqualifiedType(),
4740 ParamType.getQualifiers());
4741
4742 if (Moving) {
4743 CopyCtorArg = CastForMoving(SemaRef, CopyCtorArg);
4744 }
4745
4746 CXXCastPath BasePath;
4747 BasePath.push_back(BaseSpec);
4748 CopyCtorArg = SemaRef.ImpCastExprToType(CopyCtorArg, ArgTy,
4749 CK_UncheckedDerivedToBase,
4750 Moving ? VK_XValue : VK_LValue,
4751 &BasePath).get();
4752
4753 InitializationKind InitKind
4754 = InitializationKind::CreateDirect(Constructor->getLocation(),
4755 SourceLocation(), SourceLocation());
4756 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, CopyCtorArg);
4757 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, CopyCtorArg);
4758 break;
4759 }
4760 }
4761
4762 BaseInit = SemaRef.MaybeCreateExprWithCleanups(BaseInit);
4763 if (BaseInit.isInvalid())
4764 return true;
4765
4766 CXXBaseInit =
4767 new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4768 SemaRef.Context.getTrivialTypeSourceInfo(BaseSpec->getType(),
4769 SourceLocation()),
4770 BaseSpec->isVirtual(),
4771 SourceLocation(),
4772 BaseInit.getAs<Expr>(),
4773 SourceLocation(),
4774 SourceLocation());
4775
4776 return false;
4777}
4778
4779static bool RefersToRValueRef(Expr *MemRef) {
4780 ValueDecl *Referenced = cast<MemberExpr>(MemRef)->getMemberDecl();
4781 return Referenced->getType()->isRValueReferenceType();
4782}
4783
4784static bool
4785BuildImplicitMemberInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4786 ImplicitInitializerKind ImplicitInitKind,
4787 FieldDecl *Field, IndirectFieldDecl *Indirect,
4788 CXXCtorInitializer *&CXXMemberInit) {
4789 if (Field->isInvalidDecl())
4790 return true;
4791
4792 SourceLocation Loc = Constructor->getLocation();
4793
4794 if (ImplicitInitKind == IIK_Copy || ImplicitInitKind == IIK_Move) {
4795 bool Moving = ImplicitInitKind == IIK_Move;
4796 ParmVarDecl *Param = Constructor->getParamDecl(0);
4797 QualType ParamType = Param->getType().getNonReferenceType();
4798
4799 // Suppress copying zero-width bitfields.
4800 if (Field->isZeroLengthBitField(SemaRef.Context))
4801 return false;
4802
4803 Expr *MemberExprBase =
4804 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4805 SourceLocation(), Param, false,
4806 Loc, ParamType, VK_LValue, nullptr);
4807
4808 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(MemberExprBase));
4809
4810 if (Moving) {
4811 MemberExprBase = CastForMoving(SemaRef, MemberExprBase);
4812 }
4813
4814 // Build a reference to this field within the parameter.
4815 CXXScopeSpec SS;
4816 LookupResult MemberLookup(SemaRef, Field->getDeclName(), Loc,
4817 Sema::LookupMemberName);
4818 MemberLookup.addDecl(Indirect ? cast<ValueDecl>(Indirect)
4819 : cast<ValueDecl>(Field), AS_public);
4820 MemberLookup.resolveKind();
4821 ExprResult CtorArg
4822 = SemaRef.BuildMemberReferenceExpr(MemberExprBase,
4823 ParamType, Loc,
4824 /*IsArrow=*/false,
4825 SS,
4826 /*TemplateKWLoc=*/SourceLocation(),
4827 /*FirstQualifierInScope=*/nullptr,
4828 MemberLookup,
4829 /*TemplateArgs=*/nullptr,
4830 /*S*/nullptr);
4831 if (CtorArg.isInvalid())
4832 return true;
4833
4834 // C++11 [class.copy]p15:
4835 // - if a member m has rvalue reference type T&&, it is direct-initialized
4836 // with static_cast<T&&>(x.m);
4837 if (RefersToRValueRef(CtorArg.get())) {
4838 CtorArg = CastForMoving(SemaRef, CtorArg.get());
4839 }
4840
4841 InitializedEntity Entity =
4842 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4843 /*Implicit*/ true)
4844 : InitializedEntity::InitializeMember(Field, nullptr,
4845 /*Implicit*/ true);
4846
4847 // Direct-initialize to use the copy constructor.
4848 InitializationKind InitKind =
4849 InitializationKind::CreateDirect(Loc, SourceLocation(), SourceLocation());
4850
4851 Expr *CtorArgE = CtorArg.getAs<Expr>();
4852 InitializationSequence InitSeq(SemaRef, Entity, InitKind, CtorArgE);
4853 ExprResult MemberInit =
4854 InitSeq.Perform(SemaRef, Entity, InitKind, MultiExprArg(&CtorArgE, 1));
4855 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4856 if (MemberInit.isInvalid())
4857 return true;
4858
4859 if (Indirect)
4860 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4861 SemaRef.Context, Indirect, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4862 else
4863 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4864 SemaRef.Context, Field, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4865 return false;
4866 }
4867
4868 assert((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) &&(static_cast <bool> ((ImplicitInitKind == IIK_Default ||
ImplicitInitKind == IIK_Inherit) && "Unhandled implicit init kind!"
) ? void (0) : __assert_fail ("(ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) && \"Unhandled implicit init kind!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4869, __extension__ __PRETTY_FUNCTION__
))
4869 "Unhandled implicit init kind!")(static_cast <bool> ((ImplicitInitKind == IIK_Default ||
ImplicitInitKind == IIK_Inherit) && "Unhandled implicit init kind!"
) ? void (0) : __assert_fail ("(ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) && \"Unhandled implicit init kind!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 4869, __extension__ __PRETTY_FUNCTION__
))
;
4870
4871 QualType FieldBaseElementType =
4872 SemaRef.Context.getBaseElementType(Field->getType());
4873
4874 if (FieldBaseElementType->isRecordType()) {
4875 InitializedEntity InitEntity =
4876 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4877 /*Implicit*/ true)
4878 : InitializedEntity::InitializeMember(Field, nullptr,
4879 /*Implicit*/ true);
4880 InitializationKind InitKind =
4881 InitializationKind::CreateDefault(Loc);
4882
4883 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4884 ExprResult MemberInit =
4885 InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4886
4887 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4888 if (MemberInit.isInvalid())
4889 return true;
4890
4891 if (Indirect)
4892 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4893 Indirect, Loc,
4894 Loc,
4895 MemberInit.get(),
4896 Loc);
4897 else
4898 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4899 Field, Loc, Loc,
4900 MemberInit.get(),
4901 Loc);
4902 return false;
4903 }
4904
4905 if (!Field->getParent()->isUnion()) {
4906 if (FieldBaseElementType->isReferenceType()) {
4907 SemaRef.Diag(Constructor->getLocation(),
4908 diag::err_uninitialized_member_in_ctor)
4909 << (int)Constructor->isImplicit()
4910 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4911 << 0 << Field->getDeclName();
4912 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4913 return true;
4914 }
4915
4916 if (FieldBaseElementType.isConstQualified()) {
4917 SemaRef.Diag(Constructor->getLocation(),
4918 diag::err_uninitialized_member_in_ctor)
4919 << (int)Constructor->isImplicit()
4920 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4921 << 1 << Field->getDeclName();
4922 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4923 return true;
4924 }
4925 }
4926
4927 if (FieldBaseElementType.hasNonTrivialObjCLifetime()) {
4928 // ARC and Weak:
4929 // Default-initialize Objective-C pointers to NULL.
4930 CXXMemberInit
4931 = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
4932 Loc, Loc,
4933 new (SemaRef.Context) ImplicitValueInitExpr(Field->getType()),
4934 Loc);
4935 return false;
4936 }
4937
4938 // Nothing to initialize.
4939 CXXMemberInit = nullptr;
4940 return false;
4941}
4942
4943namespace {
4944struct BaseAndFieldInfo {
4945 Sema &S;
4946 CXXConstructorDecl *Ctor;
4947 bool AnyErrorsInInits;
4948 ImplicitInitializerKind IIK;
4949 llvm::DenseMap<const void *, CXXCtorInitializer*> AllBaseFields;
4950 SmallVector<CXXCtorInitializer*, 8> AllToInit;
4951 llvm::DenseMap<TagDecl*, FieldDecl*> ActiveUnionMember;
4952
4953 BaseAndFieldInfo(Sema &S, CXXConstructorDecl *Ctor, bool ErrorsInInits)
4954 : S(S), Ctor(Ctor), AnyErrorsInInits(ErrorsInInits) {
4955 bool Generated = Ctor->isImplicit() || Ctor->isDefaulted();
4956 if (Ctor->getInheritedConstructor())
4957 IIK = IIK_Inherit;
4958 else if (Generated && Ctor->isCopyConstructor())
4959 IIK = IIK_Copy;
4960 else if (Generated && Ctor->isMoveConstructor())
4961 IIK = IIK_Move;
4962 else
4963 IIK = IIK_Default;
4964 }
4965
4966 bool isImplicitCopyOrMove() const {
4967 switch (IIK) {
4968 case IIK_Copy:
4969 case IIK_Move:
4970 return true;
4971
4972 case IIK_Default:
4973 case IIK_Inherit:
4974 return false;
4975 }
4976
4977 llvm_unreachable("Invalid ImplicitInitializerKind!")::llvm::llvm_unreachable_internal("Invalid ImplicitInitializerKind!"
, "clang/lib/Sema/SemaDeclCXX.cpp", 4977)
;
4978 }
4979
4980 bool addFieldInitializer(CXXCtorInitializer *Init) {
4981 AllToInit.push_back(Init);
4982
4983 // Check whether this initializer makes the field "used".
4984 if (Init->getInit()->HasSideEffects(S.Context))
4985 S.UnusedPrivateFields.remove(Init->getAnyMember());
4986
4987 return false;
4988 }
4989
4990 bool isInactiveUnionMember(FieldDecl *Field) {
4991 RecordDecl *Record = Field->getParent();
4992 if (!Record->isUnion())
4993 return false;
4994
4995 if (FieldDecl *Active =
4996 ActiveUnionMember.lookup(Record->getCanonicalDecl()))
4997 return Active != Field->getCanonicalDecl();
4998
4999 // In an implicit copy or move constructor, ignore any in-class initializer.
5000 if (isImplicitCopyOrMove())
5001 return true;
5002
5003 // If there's no explicit initialization, the field is active only if it
5004 // has an in-class initializer...
5005 if (Field->hasInClassInitializer())
5006 return false;
5007 // ... or it's an anonymous struct or union whose class has an in-class
5008 // initializer.
5009 if (!Field->isAnonymousStructOrUnion())
5010 return true;
5011 CXXRecordDecl *FieldRD = Field->getType()->getAsCXXRecordDecl();
5012 return !FieldRD->hasInClassInitializer();
5013 }
5014
5015 /// Determine whether the given field is, or is within, a union member
5016 /// that is inactive (because there was an initializer given for a different
5017 /// member of the union, or because the union was not initialized at all).
5018 bool isWithinInactiveUnionMember(FieldDecl *Field,
5019 IndirectFieldDecl *Indirect) {
5020 if (!Indirect)
5021 return isInactiveUnionMember(Field);
5022
5023 for (auto *C : Indirect->chain()) {
5024 FieldDecl *Field = dyn_cast<FieldDecl>(C);
5025 if (Field && isInactiveUnionMember(Field))
5026 return true;
5027 }
5028 return false;
5029 }
5030};
5031}
5032
5033/// Determine whether the given type is an incomplete or zero-lenfgth
5034/// array type.
5035static bool isIncompleteOrZeroLengthArrayType(ASTContext &Context, QualType T) {
5036 if (T->isIncompleteArrayType())
5037 return true;
5038
5039 while (const ConstantArrayType *ArrayT = Context.getAsConstantArrayType(T)) {
5040 if (!ArrayT->getSize())
5041 return true;
5042
5043 T = ArrayT->getElementType();
5044 }
5045
5046 return false;
5047}
5048
5049static bool CollectFieldInitializer(Sema &SemaRef, BaseAndFieldInfo &Info,
5050 FieldDecl *Field,
5051 IndirectFieldDecl *Indirect = nullptr) {
5052 if (Field->isInvalidDecl())
5053 return false;
5054
5055 // Overwhelmingly common case: we have a direct initializer for this field.
5056 if (CXXCtorInitializer *Init =
5057 Info.AllBaseFields.lookup(Field->getCanonicalDecl()))
5058 return Info.addFieldInitializer(Init);
5059
5060 // C++11 [class.base.init]p8:
5061 // if the entity is a non-static data member that has a
5062 // brace-or-equal-initializer and either
5063 // -- the constructor's class is a union and no other variant member of that
5064 // union is designated by a mem-initializer-id or
5065 // -- the constructor's class is not a union, and, if the entity is a member
5066 // of an anonymous union, no other member of that union is designated by
5067 // a mem-initializer-id,
5068 // the entity is initialized as specified in [dcl.init].
5069 //
5070 // We also apply the same rules to handle anonymous structs within anonymous
5071 // unions.
5072 if (Info.isWithinInactiveUnionMember(Field, Indirect))
5073 return false;
5074
5075 if (Field->hasInClassInitializer() && !Info.isImplicitCopyOrMove()) {
5076 ExprResult DIE =
5077 SemaRef.BuildCXXDefaultInitExpr(Info.Ctor->getLocation(), Field);
5078 if (DIE.isInvalid())
5079 return true;
5080
5081 auto Entity = InitializedEntity::InitializeMember(Field, nullptr, true);
5082 SemaRef.checkInitializerLifetime(Entity, DIE.get());
5083
5084 CXXCtorInitializer *Init;
5085 if (Indirect)
5086 Init = new (SemaRef.Context)
5087 CXXCtorInitializer(SemaRef.Context, Indirect, SourceLocation(),
5088 SourceLocation(), DIE.get(), SourceLocation());
5089 else
5090 Init = new (SemaRef.Context)
5091 CXXCtorInitializer(SemaRef.Context, Field, SourceLocation(),
5092 SourceLocation(), DIE.get(), SourceLocation());
5093 return Info.addFieldInitializer(Init);
5094 }
5095
5096 // Don't initialize incomplete or zero-length arrays.
5097 if (isIncompleteOrZeroLengthArrayType(SemaRef.Context, Field->getType()))
5098 return false;
5099
5100 // Don't try to build an implicit initializer if there were semantic
5101 // errors in any of the initializers (and therefore we might be
5102 // missing some that the user actually wrote).
5103 if (Info.AnyErrorsInInits)
5104 return false;
5105
5106 CXXCtorInitializer *Init = nullptr;
5107 if (BuildImplicitMemberInitializer(Info.S, Info.Ctor, Info.IIK, Field,
5108 Indirect, Init))
5109 return true;
5110
5111 if (!Init)
5112 return false;
5113
5114 return Info.addFieldInitializer(Init);
5115}
5116
5117bool
5118Sema::SetDelegatingInitializer(CXXConstructorDecl *Constructor,
5119 CXXCtorInitializer *Initializer) {
5120 assert(Initializer->isDelegatingInitializer())(static_cast <bool> (Initializer->isDelegatingInitializer
()) ? void (0) : __assert_fail ("Initializer->isDelegatingInitializer()"
, "clang/lib/Sema/SemaDeclCXX.cpp", 5120, __extension__ __PRETTY_FUNCTION__
))
;
5121 Constructor->setNumCtorInitializers(1);
5122 CXXCtorInitializer **initializer =
5123 new (Context) CXXCtorInitializer*[1];
5124 memcpy(initializer, &Initializer, sizeof (CXXCtorInitializer*));
5125 Constructor->setCtorInitializers(initializer);
5126
5127 if (CXXDestructorDecl *Dtor = LookupDestructor(Constructor->getParent())) {
5128 MarkFunctionReferenced(Initializer->getSourceLocation(), Dtor);
5129 DiagnoseUseOfDecl(Dtor, Initializer->getSourceLocation());
5130 }
5131
5132 DelegatingCtorDecls.push_back(Constructor);
5133
5134 DiagnoseUninitializedFields(*this, Constructor);
5135
5136 return false;
5137}
5138
5139bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
5140 ArrayRef<CXXCtorInitializer *> Initializers) {
5141 if (Constructor->isDependentContext()) {
5142 // Just store the initializers as written, they will be checked during
5143 // instantiation.
5144 if (!Initializers.empty()) {
5145 Constructor->setNumCtorInitializers(Initializers.size());
5146 CXXCtorInitializer **baseOrMemberInitializers =
5147 new (Context) CXXCtorInitializer*[Initializers.size()];
5148 memcpy(baseOrMemberInitializers, Initializers.data(),
5149 Initializers.size() * sizeof(CXXCtorInitializer*));
5150 Constructor->setCtorInitializers(baseOrMemberInitializers);
5151 }
5152
5153 // Let template instantiation know whether we had errors.
5154 if (AnyErrors)
5155 Constructor->setInvalidDecl();
5156
5157 return false;
5158 }
5159
5160 BaseAndFieldInfo Info(*this, Constructor, AnyErrors);
5161
5162 // We need to build the initializer AST according to order of construction
5163 // and not what user specified in the Initializers list.
5164 CXXRecordDecl *ClassDecl = Constructor->getParent()->getDefinition();
5165 if (!ClassDecl)
5166 return true;
5167
5168 bool HadError = false;
5169
5170 for (unsigned i = 0; i < Initializers.size(); i++) {
5171 CXXCtorInitializer *Member = Initializers[i];
5172
5173 if (Member->isBaseInitializer())
5174 Info.AllBaseFields[Member->getBaseClass()->getAs<RecordType>()] = Member;
5175 else {
5176 Info.AllBaseFields[Member->getAnyMember()->getCanonicalDecl()] = Member;
5177
5178 if (IndirectFieldDecl *F = Member->getIndirectMember()) {
5179 for (auto *C : F->chain()) {
5180 FieldDecl *FD = dyn_cast<FieldDecl>(C);
5181 if (FD && FD->getParent()->isUnion())
5182 Info.ActiveUnionMember.insert(std::make_pair(
5183 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
5184 }
5185 } else if (FieldDecl *FD = Member->getMember()) {
5186 if (FD->getParent()->isUnion())
5187 Info.ActiveUnionMember.insert(std::make_pair(
5188 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
5189 }
5190 }
5191 }
5192
5193 // Keep track of the direct virtual bases.
5194 llvm::SmallPtrSet<CXXBaseSpecifier *, 16> DirectVBases;
5195 for (auto &I : ClassDecl->bases()) {
5196 if (I.isVirtual())
5197 DirectVBases.insert(&I);
5198 }
5199
5200 // Push virtual bases before others.
5201 for (auto &VBase : ClassDecl->vbases()) {
5202 if (CXXCtorInitializer *Value
5203 = Info.AllBaseFields.lookup(VBase.getType()->getAs<RecordType>())) {
5204 // [class.base.init]p7, per DR257:
5205 // A mem-initializer where the mem-initializer-id names a virtual base
5206 // class is ignored during execution of a constructor of any class that
5207 // is not the most derived class.
5208 if (ClassDecl->isAbstract()) {
5209 // FIXME: Provide a fixit to remove the base specifier. This requires
5210 // tracking the location of the associated comma for a base specifier.
5211 Diag(Value->getSourceLocation(), diag::warn_abstract_vbase_init_ignored)
5212 << VBase.getType() << ClassDecl;
5213 DiagnoseAbstractType(ClassDecl);
5214 }
5215
5216 Info.AllToInit.push_back(Value);
5217 } else if (!AnyErrors && !ClassDecl->isAbstract()) {
5218 // [class.base.init]p8, per DR257:
5219 // If a given [...] base class is not named by a mem-initializer-id
5220 // [...] and the entity is not a virtual base class of an abstract
5221 // class, then [...] the entity is default-initialized.
5222 bool IsInheritedVirtualBase = !DirectVBases.count(&VBase);
5223 CXXCtorInitializer *CXXBaseInit;
5224 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
5225 &VBase, IsInheritedVirtualBase,
5226 CXXBaseInit)) {
5227 HadError = true;
5228 continue;
5229 }
5230
5231 Info.AllToInit.push_back(CXXBaseInit);
5232 }
5233 }
5234
5235 // Non-virtual bases.
5236 for (auto &Base : ClassDecl->bases()) {
5237 // Virtuals are in the virtual base list and already constructed.
5238 if (Base.isVirtual())
5239 continue;
5240
5241 if (CXXCtorInitializer *Value
5242 = Info.AllBaseFields.lookup(Base.getType()->getAs<RecordType>())) {
5243 Info.AllToInit.push_back(Value);
5244 } else if (!AnyErrors) {
5245 CXXCtorInitializer *CXXBaseInit;
5246 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
5247 &Base, /*IsInheritedVirtualBase=*/false,
5248 CXXBaseInit)) {
5249 HadError = true;
5250 continue;
5251 }
5252
5253 Info.AllToInit.push_back(CXXBaseInit);
5254 }
5255 }
5256
5257 // Fields.
5258 for (auto *Mem : ClassDecl->decls()) {
5259 if (auto *F = dyn_cast<FieldDecl>(Mem)) {
5260 // C++ [class.bit]p2:
5261 // A declaration for a bit-field that omits the identifier declares an
5262 // unnamed bit-field. Unnamed bit-fields are not members and cannot be
5263 // initialized.
5264 if (F->isUnnamedBitfield())
5265 continue;
5266
5267 // If we're not generating the implicit copy/move constructor, then we'll
5268 // handle anonymous struct/union fields based on their individual
5269 // indirect fields.
5270 if (F->isAnonymousStructOrUnion() && !Info.isImplicitCopyOrMove())
5271 continue;
5272
5273 if (CollectFieldInitializer(*this, Info, F))
5274 HadError = true;
5275 continue;
5276 }
5277
5278 // Beyond this point, we only consider default initialization.
5279 if (Info.isImplicitCopyOrMove())
5280 continue;
5281
5282 if (auto *F = dyn_cast<IndirectFieldDecl>(Mem)) {
5283 if (F->getType()->isIncompleteArrayType()) {
5284 assert(ClassDecl->hasFlexibleArrayMember() &&(static_cast <bool> (ClassDecl->hasFlexibleArrayMember
() && "Incomplete array type is not valid") ? void (0
) : __assert_fail ("ClassDecl->hasFlexibleArrayMember() && \"Incomplete array type is not valid\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 5285, __extension__ __PRETTY_FUNCTION__
))
5285 "Incomplete array type is not valid")(static_cast <bool> (ClassDecl->hasFlexibleArrayMember
() && "Incomplete array type is not valid") ? void (0
) : __assert_fail ("ClassDecl->hasFlexibleArrayMember() && \"Incomplete array type is not valid\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 5285, __extension__ __PRETTY_FUNCTION__
))
;
5286 continue;
5287 }
5288
5289 // Initialize each field of an anonymous struct individually.
5290 if (CollectFieldInitializer(*this, Info, F->getAnonField(), F))
5291 HadError = true;
5292
5293 continue;
5294 }
5295 }
5296
5297 unsigned NumInitializers = Info.AllToInit.size();
5298 if (NumInitializers > 0) {
5299 Constructor->setNumCtorInitializers(NumInitializers);
5300 CXXCtorInitializer **baseOrMemberInitializers =
5301 new (Context) CXXCtorInitializer*[NumInitializers];
5302 memcpy(baseOrMemberInitializers, Info.AllToInit.data(),
5303 NumInitializers * sizeof(CXXCtorInitializer*));
5304 Constructor->setCtorInitializers(baseOrMemberInitializers);
5305
5306 // Constructors implicitly reference the base and member
5307 // destructors.
5308 MarkBaseAndMemberDestructorsReferenced(Constructor->getLocation(),
5309 Constructor->getParent());
5310 }
5311
5312 return HadError;
5313}
5314
5315static void PopulateKeysForFields(FieldDecl *Field, SmallVectorImpl<const void*> &IdealInits) {
5316 if (const RecordType *RT = Field->getType()->getAs<RecordType>()) {
5317 const RecordDecl *RD = RT->getDecl();
5318 if (RD->isAnonymousStructOrUnion()) {
5319 for (auto *Field : RD->fields())
5320 PopulateKeysForFields(Field, IdealInits);
5321 return;
5322 }
5323 }
5324 IdealInits.push_back(Field->getCanonicalDecl());
5325}
5326
5327static const void *GetKeyForBase(ASTContext &Context, QualType BaseType) {
5328 return Context.getCanonicalType(BaseType).getTypePtr();
5329}
5330
5331static const void *GetKeyForMember(ASTContext &Context,
5332 CXXCtorInitializer *Member) {
5333 if (!Member->isAnyMemberInitializer())
5334 return GetKeyForBase(Context, QualType(Member->getBaseClass(), 0));
5335
5336 return Member->getAnyMember()->getCanonicalDecl();
5337}
5338
5339static void AddInitializerToDiag(const Sema::SemaDiagnosticBuilder &Diag,
5340 const CXXCtorInitializer *Previous,
5341 const CXXCtorInitializer *Current) {
5342 if (Previous->isAnyMemberInitializer())
5343 Diag << 0 << Previous->getAnyMember();
5344 else
5345 Diag << 1 << Previous->getTypeSourceInfo()->getType();
5346
5347 if (Current->isAnyMemberInitializer())
5348 Diag << 0 << Current->getAnyMember();
5349 else
5350 Diag << 1 << Current->getTypeSourceInfo()->getType();
5351}
5352
5353static void DiagnoseBaseOrMemInitializerOrder(
5354 Sema &SemaRef, const CXXConstructorDecl *Constructor,
5355 ArrayRef<CXXCtorInitializer *> Inits) {
5356 if (Constructor->getDeclContext()->isDependentContext())
5357 return;
5358
5359 // Don't check initializers order unless the warning is enabled at the
5360 // location of at least one initializer.
5361 bool ShouldCheckOrder = false;
5362 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
5363 CXXCtorInitializer *Init = Inits[InitIndex];
5364 if (!SemaRef.Diags.isIgnored(diag::warn_initializer_out_of_order,
5365 Init->getSourceLocation())) {
5366 ShouldCheckOrder = true;
5367 break;
5368 }
5369 }
5370 if (!ShouldCheckOrder)
5371 return;
5372
5373 // Build the list of bases and members in the order that they'll
5374 // actually be initialized. The explicit initializers should be in
5375 // this same order but may be missing things.
5376 SmallVector<const void*, 32> IdealInitKeys;
5377
5378 const CXXRecordDecl *ClassDecl = Constructor->getParent();
5379
5380 // 1. Virtual bases.
5381 for (const auto &VBase : ClassDecl->vbases())
5382 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, VBase.getType()));
5383
5384 // 2. Non-virtual bases.
5385 for (const auto &Base : ClassDecl->bases()) {
5386 if (Base.isVirtual())
5387 continue;
5388 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, Base.getType()));
5389 }
5390
5391 // 3. Direct fields.
5392 for (auto *Field : ClassDecl->fields()) {
5393 if (Field->isUnnamedBitfield())
5394 continue;
5395
5396 PopulateKeysForFields(Field, IdealInitKeys);
5397 }
5398
5399 unsigned NumIdealInits = IdealInitKeys.size();
5400 unsigned IdealIndex = 0;
5401
5402 // Track initializers that are in an incorrect order for either a warning or
5403 // note if multiple ones occur.
5404 SmallVector<unsigned> WarnIndexes;
5405 // Correlates the index of an initializer in the init-list to the index of
5406 // the field/base in the class.
5407 SmallVector<std::pair<unsigned, unsigned>, 32> CorrelatedInitOrder;
5408
5409 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
5410 const void *InitKey = GetKeyForMember(SemaRef.Context, Inits[InitIndex]);
5411
5412 // Scan forward to try to find this initializer in the idealized
5413 // initializers list.
5414 for (; IdealIndex != NumIdealInits; ++IdealIndex)
5415 if (InitKey == IdealInitKeys[IdealIndex])
5416 break;
5417
5418 // If we didn't find this initializer, it must be because we
5419 // scanned past it on a previous iteration. That can only
5420 // happen if we're out of order; emit a warning.
5421 if (IdealIndex == NumIdealInits && InitIndex) {
5422 WarnIndexes.push_back(InitIndex);
5423
5424 // Move back to the initializer's location in the ideal list.
5425 for (IdealIndex = 0; IdealIndex != NumIdealInits; ++IdealIndex)
5426 if (InitKey == IdealInitKeys[IdealIndex])
5427 break;
5428
5429 assert(IdealIndex < NumIdealInits &&(static_cast <bool> (IdealIndex < NumIdealInits &&
"initializer not found in initializer list") ? void (0) : __assert_fail
("IdealIndex < NumIdealInits && \"initializer not found in initializer list\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 5430, __extension__ __PRETTY_FUNCTION__
))
5430 "initializer not found in initializer list")(static_cast <bool> (IdealIndex < NumIdealInits &&
"initializer not found in initializer list") ? void (0) : __assert_fail
("IdealIndex < NumIdealInits && \"initializer not found in initializer list\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 5430, __extension__ __PRETTY_FUNCTION__
))
;
5431 }
5432 CorrelatedInitOrder.emplace_back(IdealIndex, InitIndex);
5433 }
5434
5435 if (WarnIndexes.empty())
5436 return;
5437
5438 // Sort based on the ideal order, first in the pair.
5439 llvm::sort(CorrelatedInitOrder, llvm::less_first());
5440
5441 // Introduce a new scope as SemaDiagnosticBuilder needs to be destroyed to
5442 // emit the diagnostic before we can try adding notes.
5443 {
5444 Sema::SemaDiagnosticBuilder D = SemaRef.Diag(
5445 Inits[WarnIndexes.front() - 1]->getSourceLocation(),
5446 WarnIndexes.size() == 1 ? diag::warn_initializer_out_of_order
5447 : diag::warn_some_initializers_out_of_order);
5448
5449 for (unsigned I = 0; I < CorrelatedInitOrder.size(); ++I) {
5450 if (CorrelatedInitOrder[I].second == I)
5451 continue;
5452 // Ideally we would be using InsertFromRange here, but clang doesn't
5453 // appear to handle InsertFromRange correctly when the source range is
5454 // modified by another fix-it.
5455 D << FixItHint::CreateReplacement(
5456 Inits[I]->getSourceRange(),
5457 Lexer::getSourceText(
5458 CharSourceRange::getTokenRange(
5459 Inits[CorrelatedInitOrder[I].second]->getSourceRange()),
5460 SemaRef.getSourceManager(), SemaRef.getLangOpts()));
5461 }
5462
5463 // If there is only 1 item out of order, the warning expects the name and
5464 // type of each being added to it.
5465 if (WarnIndexes.size() == 1) {
5466 AddInitializerToDiag(D, Inits[WarnIndexes.front() - 1],
5467 Inits[WarnIndexes.front()]);
5468 return;
5469 }
5470 }
5471 // More than 1 item to warn, create notes letting the user know which ones
5472 // are bad.
5473 for (unsigned WarnIndex : WarnIndexes) {
5474 const clang::CXXCtorInitializer *PrevInit = Inits[WarnIndex - 1];
5475 auto D = SemaRef.Diag(PrevInit->getSourceLocation(),
5476 diag::note_initializer_out_of_order);
5477 AddInitializerToDiag(D, PrevInit, Inits[WarnIndex]);
5478 D << PrevInit->getSourceRange();
5479 }
5480}
5481
5482namespace {
5483bool CheckRedundantInit(Sema &S,
5484 CXXCtorInitializer *Init,
5485 CXXCtorInitializer *&PrevInit) {
5486 if (!PrevInit) {
5487 PrevInit = Init;
5488 return false;
5489 }
5490
5491 if (FieldDecl *Field = Init->getAnyMember())
5492 S.Diag(Init->getSourceLocation(),
5493 diag::err_multiple_mem_initialization)
5494 << Field->getDeclName()
5495 << Init->getSourceRange();
5496 else {
5497 const Type *BaseClass = Init->getBaseClass();
5498 assert(BaseClass && "neither field nor base")(static_cast <bool> (BaseClass && "neither field nor base"
) ? void (0) : __assert_fail ("BaseClass && \"neither field nor base\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 5498, __extension__ __PRETTY_FUNCTION__
))
;
5499 S.Diag(Init->getSourceLocation(),
5500 diag::err_multiple_base_initialization)
5501 << QualType(BaseClass, 0)
5502 << Init->getSourceRange();
5503 }
5504 S.Diag(PrevInit->getSourceLocation(), diag::note_previous_initializer)
5505 << 0 << PrevInit->getSourceRange();
5506
5507 return true;
5508}
5509
5510typedef std::pair<NamedDecl *, CXXCtorInitializer *> UnionEntry;
5511typedef llvm::DenseMap<RecordDecl*, UnionEntry> RedundantUnionMap;
5512
5513bool CheckRedundantUnionInit(Sema &S,
5514 CXXCtorInitializer *Init,
5515 RedundantUnionMap &Unions) {
5516 FieldDecl *Field = Init->getAnyMember();
5517 RecordDecl *Parent = Field->getParent();
5518 NamedDecl *Child = Field;
5519
5520 while (Parent->isAnonymousStructOrUnion() || Parent->isUnion()) {
5521 if (Parent->isUnion()) {
5522 UnionEntry &En = Unions[Parent];
5523 if (En.first && En.first != Child) {
5524 S.Diag(Init->getSourceLocation(),
5525 diag::err_multiple_mem_union_initialization)
5526 << Field->getDeclName()
5527 << Init->getSourceRange();
5528 S.Diag(En.second->getSourceLocation(), diag::note_previous_initializer)
5529 << 0 << En.second->getSourceRange();
5530 return true;
5531 }
5532 if (!En.first) {
5533 En.first = Child;
5534 En.second = Init;
5535 }
5536 if (!Parent->isAnonymousStructOrUnion())
5537 return false;
5538 }
5539
5540 Child = Parent;
5541 Parent = cast<RecordDecl>(Parent->getDeclContext());
5542 }
5543
5544 return false;
5545}
5546} // namespace
5547
5548/// ActOnMemInitializers - Handle the member initializers for a constructor.
5549void Sema::ActOnMemInitializers(Decl *ConstructorDecl,
5550 SourceLocation ColonLoc,
5551 ArrayRef<CXXCtorInitializer*> MemInits,
5552 bool AnyErrors) {
5553 if (!ConstructorDecl)
5554 return;
5555
5556 AdjustDeclIfTemplate(ConstructorDecl);
5557
5558 CXXConstructorDecl *Constructor
5559 = dyn_cast<CXXConstructorDecl>(ConstructorDecl);
5560
5561 if (!Constructor) {
5562 Diag(ColonLoc, diag::err_only_constructors_take_base_inits);
5563 return;
5564 }
5565
5566 // Mapping for the duplicate initializers check.
5567 // For member initializers, this is keyed with a FieldDecl*.
5568 // For base initializers, this is keyed with a Type*.
5569 llvm::DenseMap<const void *, CXXCtorInitializer *> Members;
5570
5571 // Mapping for the inconsistent anonymous-union initializers check.
5572 RedundantUnionMap MemberUnions;
5573
5574 bool HadError = false;
5575 for (unsigned i = 0; i < MemInits.size(); i++) {
5576 CXXCtorInitializer *Init = MemInits[i];
5577
5578 // Set the source order index.
5579 Init->setSourceOrder(i);
5580
5581 if (Init->isAnyMemberInitializer()) {
5582 const void *Key = GetKeyForMember(Context, Init);
5583 if (CheckRedundantInit(*this, Init, Members[Key]) ||
5584 CheckRedundantUnionInit(*this, Init, MemberUnions))
5585 HadError = true;
5586 } else if (Init->isBaseInitializer()) {
5587 const void *Key = GetKeyForMember(Context, Init);
5588 if (CheckRedundantInit(*this, Init, Members[Key]))
5589 HadError = true;
5590 } else {
5591 assert(Init->isDelegatingInitializer())(static_cast <bool> (Init->isDelegatingInitializer()
) ? void (0) : __assert_fail ("Init->isDelegatingInitializer()"
, "clang/lib/Sema/SemaDeclCXX.cpp", 5591, __extension__ __PRETTY_FUNCTION__
))
;
5592 // This must be the only initializer
5593 if (MemInits.size() != 1) {
5594 Diag(Init->getSourceLocation(),
5595 diag::err_delegating_initializer_alone)
5596 << Init->getSourceRange() << MemInits[i ? 0 : 1]->getSourceRange();
5597 // We will treat this as being the only initializer.
5598 }
5599 SetDelegatingInitializer(Constructor, MemInits[i]);
5600 // Return immediately as the initializer is set.
5601 return;
5602 }
5603 }
5604
5605 if (HadError)
5606 return;
5607
5608 DiagnoseBaseOrMemInitializerOrder(*this, Constructor, MemInits);
5609
5610 SetCtorInitializers(Constructor, AnyErrors, MemInits);
5611
5612 DiagnoseUninitializedFields(*this, Constructor);
5613}
5614
5615void
5616Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
5617 CXXRecordDecl *ClassDecl) {
5618 // Ignore dependent contexts. Also ignore unions, since their members never
5619 // have destructors implicitly called.
5620 if (ClassDecl->isDependentContext() || ClassDecl->isUnion())
5621 return;
5622
5623 // FIXME: all the access-control diagnostics are positioned on the
5624 // field/base declaration. That's probably good; that said, the
5625 // user might reasonably want to know why the destructor is being
5626 // emitted, and we currently don't say.
5627
5628 // Non-static data members.
5629 for (auto *Field : ClassDecl->fields()) {
5630 if (Field->isInvalidDecl())
5631 continue;
5632
5633 // Don't destroy incomplete or zero-length arrays.
5634 if (isIncompleteOrZeroLengthArrayType(Context, Field->getType()))
5635 continue;
5636
5637 QualType FieldType = Context.getBaseElementType(Field->getType());
5638
5639 const RecordType* RT = FieldType->getAs<RecordType>();
5640 if (!RT)
5641 continue;
5642
5643 CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5644 if (FieldClassDecl->isInvalidDecl())
5645 continue;
5646 if (FieldClassDecl->hasIrrelevantDestructor())
5647 continue;
5648 // The destructor for an implicit anonymous union member is never invoked.
5649 if (FieldClassDecl->isUnion() && FieldClassDecl->isAnonymousStructOrUnion())
5650 continue;
5651
5652 CXXDestructorDecl *Dtor = LookupDestructor(FieldClassDecl);
5653 assert(Dtor && "No dtor found for FieldClassDecl!")(static_cast <bool> (Dtor && "No dtor found for FieldClassDecl!"
) ? void (0) : __assert_fail ("Dtor && \"No dtor found for FieldClassDecl!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 5653, __extension__ __PRETTY_FUNCTION__
))
;
5654 CheckDestructorAccess(Field->getLocation(), Dtor,
5655 PDiag(diag::err_access_dtor_field)
5656 << Field->getDeclName()
5657 << FieldType);
5658
5659 MarkFunctionReferenced(Location, Dtor);
5660 DiagnoseUseOfDecl(Dtor, Location);
5661 }
5662
5663 // We only potentially invoke the destructors of potentially constructed
5664 // subobjects.
5665 bool VisitVirtualBases = !ClassDecl->isAbstract();
5666
5667 // If the destructor exists and has already been marked used in the MS ABI,
5668 // then virtual base destructors have already been checked and marked used.
5669 // Skip checking them again to avoid duplicate diagnostics.
5670 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
5671 CXXDestructorDecl *Dtor = ClassDecl->getDestructor();
5672 if (Dtor && Dtor->isUsed())
5673 VisitVirtualBases = false;
5674 }
5675
5676 llvm::SmallPtrSet<const RecordType *, 8> DirectVirtualBases;
5677
5678 // Bases.
5679 for (const auto &Base : ClassDecl->bases()) {
5680 const RecordType *RT = Base.getType()->getAs<RecordType>();
5681 if (!RT)
5682 continue;
5683
5684 // Remember direct virtual bases.
5685 if (Base.isVirtual()) {
5686 if (!VisitVirtualBases)
5687 continue;
5688 DirectVirtualBases.insert(RT);
5689 }
5690
5691 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5692 // If our base class is invalid, we probably can't get its dtor anyway.
5693 if (BaseClassDecl->isInvalidDecl())
5694 continue;
5695 if (BaseClassDecl->hasIrrelevantDestructor())
5696 continue;
5697
5698 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5699 assert(Dtor && "No dtor found for BaseClassDecl!")(static_cast <bool> (Dtor && "No dtor found for BaseClassDecl!"
) ? void (0) : __assert_fail ("Dtor && \"No dtor found for BaseClassDecl!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 5699, __extension__ __PRETTY_FUNCTION__
))
;
5700
5701 // FIXME: caret should be on the start of the class name
5702 CheckDestructorAccess(Base.getBeginLoc(), Dtor,
5703 PDiag(diag::err_access_dtor_base)
5704 << Base.getType() << Base.getSourceRange(),
5705 Context.getTypeDeclType(ClassDecl));
5706
5707 MarkFunctionReferenced(Location, Dtor);
5708 DiagnoseUseOfDecl(Dtor, Location);
5709 }
5710
5711 if (VisitVirtualBases)
5712 MarkVirtualBaseDestructorsReferenced(Location, ClassDecl,
5713 &DirectVirtualBases);
5714}
5715
5716void Sema::MarkVirtualBaseDestructorsReferenced(
5717 SourceLocation Location, CXXRecordDecl *ClassDecl,
5718 llvm::SmallPtrSetImpl<const RecordType *> *DirectVirtualBases) {
5719 // Virtual bases.
5720 for (const auto &VBase : ClassDecl->vbases()) {
5721 // Bases are always records in a well-formed non-dependent class.
5722 const RecordType *RT = VBase.getType()->castAs<RecordType>();
5723
5724 // Ignore already visited direct virtual bases.
5725 if (DirectVirtualBases && DirectVirtualBases->count(RT))
5726 continue;
5727
5728 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5729 // If our base class is invalid, we probably can't get its dtor anyway.
5730 if (BaseClassDecl->isInvalidDecl())
5731 continue;
5732 if (BaseClassDecl->hasIrrelevantDestructor())
5733 continue;
5734
5735 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5736 assert(Dtor && "No dtor found for BaseClassDecl!")(static_cast <bool> (Dtor && "No dtor found for BaseClassDecl!"
) ? void (0) : __assert_fail ("Dtor && \"No dtor found for BaseClassDecl!\""
, "clang/lib/Sema/SemaDeclCXX.cpp", 5736, __extension__ __PRETTY_FUNCTION__
))
;
5737 if (CheckDestructorAccess(
5738 ClassDecl->getLocation(), Dtor,
5739 PDiag(diag::err_access_dtor_vbase)
5740 << Context.getTypeDeclType(ClassDecl) << VBase.getType(),
5741 Context.getTypeDeclType(ClassDecl)) ==
5742 AR_accessible) {
5743 CheckDerivedToBaseConversion(
5744 Context.getTypeDeclType(ClassDecl), VBase.getType(),
5745 diag::err_access_dtor_vbase, 0, ClassDecl->getLocation(),
5746 SourceRange(), DeclarationName(), nullptr);
5747 }
5748
5749 MarkFunctionReferenced(Location, Dtor);
5750 DiagnoseUseOfDecl(Dtor, Location);
5751 }
5752}
5753
5754void Sema::ActOnDefaultCtorInitializers(Decl *CDtorDecl) {
5755 if (!CDtorDecl)
5756 return;
5757
5758 if (CXXConstructorDecl *Constructor
5759 = dyn_cast<CXXConstructorDecl>(CDtorDecl)) {
5760 SetCtorInitializers(Constructor, /*AnyErrors=*/false);
5761 DiagnoseUninitializedFields(*this, Constructor);
5762 }
5763}
5764
5765bool Sema::isAbstractType(SourceLocation Loc, QualType T) {
5766 if (!getLangOpts().CPlusPlus)
5767 return false;
5768
5769 const auto *RD = Context.getBaseElementType(T)->getAsCXXRecordDecl();
5770 if (!RD)
5771 return false;
5772
5773 // FIXME: Per [temp.inst]p1, we are supposed to trigger instantiation of a
5774 // class template specialization here, but doing so breaks a lot of code.
5775
5776 // We can't answer whether something is abstract until it has a
5777 // definition. If it's currently being defined, we'll walk back
5778 // over all the declarations when we have a full definition.
5779 const CXXRecordDecl *Def = RD->getDefinition();
5780 if (!Def || Def->isBeingDefined())
5781 return false;
5782
5783 return RD->isAbstract();
5784}
5785
5786bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T,
5787 TypeDiagnoser &Diagnoser) {
5788 if (!isAbstractType(Loc, T))
5789 return false;
5790
5791 T = Context.getBaseElementType(T);
5792 Diagnoser.diagnose(*this, Loc, T);
5793 DiagnoseAbstractType(T->getAsCXXRecordDecl());
5794 return true;
5795}
5796
5797void Sema::DiagnoseAbstractType(const CXXRecordDecl *RD) {
5798 // Check if we've already emitted the list of pure virtual functions
5799 // for this class.
5800 if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD))
5801 return;
5802
5803 // If the diagnostic is suppressed, don't emit the notes. We're only
5804 // going to emit them once, so try to attach them to a diagnostic we're
5805 // actually going to show.
5806 if (Diags.isLastDiagnosticIgnored())
5807 return;
5808
5809 CXXFinalOverriderMap FinalOverriders;
5810 RD->getFinalOverriders(FinalOverriders);
5811
5812 // Keep a set of seen pure methods so we won't diagnose the same method
5813 // more than once.
5814 llvm::SmallPtrSet<const CXXMethodDecl *, 8> SeenPureMethods;
5815
5816 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
5817 MEnd = FinalOverriders.end();
5818 M != MEnd;
5819 ++M) {
5820 for (OverridingMethods::iterator SO = M->second.begin(),
5821 SOEnd = M->second.end();
5822 SO != SOEnd; ++SO) {
5823 // C++ [class.abstract]p4:
5824 // A class is abstract if it contains or inherits at least one
5825 // pure virtual function for which the final overrider is pure
5826 // virtual.
5827
5828 //
5829 if (SO->second.size() != 1)
5830 continue;
5831
5832 if (!SO->second.front().Method->isPure())
5833 continue;
5834
5835 if (!SeenPureMethods.insert(SO->second.front().Method).second)
5836 continue;
5837
5838 Diag(SO->second.front().Method->getLocation(),
5839 diag::note_pure_virtual_function)
5840 << SO->second.front().Method->getDeclName() << RD->getDeclName();
5841 }
5842 }
5843
5844 if (!PureVirtualClassDiagSet)
5845 PureVirtualClassDiagSet.reset(new RecordDeclSetTy);
5846 PureVirtualClassDiagSet->insert(RD);
5847}
5848
5849namespace {
5850struct AbstractUsageInfo {
5851 Sema &S;
5852 CXXRecordDecl *Record;
5853 CanQualType AbstractType;
5854 bool Invalid;
5855
5856 AbstractUsageInfo(Sema &S, CXXRecordDecl *Record)
5857 : S(S), Record(Record),
5858 AbstractType(S.Context.getCanonicalType(
5859 S.Context.getTypeDeclType(Record))),
5860 Invalid(false) {}
5861
5862 void DiagnoseAbstractType() {
5863 if (Invalid) return;
5864 S.DiagnoseAbstractType(Record);
5865 Invalid = true;
5866 }
5867
5868 void CheckType(const NamedDecl *D, TypeLoc TL, Sema::AbstractDiagSelID Sel);
5869};
5870
5871struct CheckAbstractUsage {
5872 AbstractUsageInfo &Info;
5873 const NamedDecl *Ctx;
5874
5875 CheckAbstractUsage(AbstractUsageInfo &Info, const NamedDecl *Ctx)
5876 : Info(Info), Ctx(Ctx) {}
5877
5878 void Visit(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
5879 switch (TL.getTypeLocClass()) {
5880#define ABSTRACT_TYPELOC(CLASS, PARENT)
5881#define TYPELOC(CLASS, PARENT) \
5882 case TypeLoc::CLASS: Check(TL.castAs<CLASS##TypeLoc>(), Sel); break;
5883#include "clang/AST/TypeLocNodes.def"
5884 }
5885 }
5886
5887 void Check(FunctionProtoTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5888 Visit(TL.getReturnLoc(), Sema::AbstractReturnType);
5889 for (unsigned I = 0, E = TL.getNumParams(); I != E; ++I) {
5890 if (!TL.getParam(I))
5891 continue;
5892
5893 TypeSourceInfo *TSI = TL.getParam(I)->getTypeSourceInfo();
5894 if (TSI) Visit(TSI->getTypeLoc(), Sema::AbstractParamType);
5895 }
5896 }
5897
5898 void Check(ArrayTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5899 Visit(TL.getElementLoc(), Sema::AbstractArrayType);
5900 }
5901
5902 void Check(TemplateSpecializationTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5903 // Visit the type parameters from a permissive context.
5904 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) {
5905 TemplateArgumentLoc TAL = TL.getArgLoc(I);
5906 if (TAL.getArgument().getKind() == TemplateArgument::Type)
5907 if (TypeSourceInfo *TSI = TAL.getTypeSourceInfo())
5908 Visit(TSI->getTypeLoc(), Sema::AbstractNone);
5909 // TODO: other template argument types?
5910 }
5911 }
5912
5913 // Visit pointee types from a permissive context.
5914#define CheckPolymorphic(Type)void Check(Type TL, Sema::AbstractDiagSelID Sel) { Visit(TL.getNextTypeLoc
(), Sema::AbstractNone); }
\
5915 void Check(Type TL, Sema::AbstractDiagSelID Sel) { \
5916 Visit(TL.getNextTypeLoc(), Sema::AbstractNone); \
5917 }
5918 CheckPolymorphic(PointerTypeLoc)void Check(PointerTypeLoc TL, Sema::AbstractDiagSelID Sel) { Visit
(TL.getNextTypeLoc(), Sema::AbstractNone); }
5919 CheckPolymorphic(ReferenceTypeLoc)void Check(ReferenceTypeLoc TL, Sema::AbstractDiagSelID Sel) {
Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5920 CheckPolymorphic(MemberPointerTypeLoc)void Check(MemberPointerTypeLoc TL, Sema::AbstractDiagSelID Sel
) { Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5921 CheckPolymorphic(BlockPointerTypeLoc)void Check(BlockPointerTypeLoc TL, Sema::AbstractDiagSelID Sel
) { Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5922 CheckPolymorphic(AtomicTypeLoc)void Check(AtomicTypeLoc TL, Sema::AbstractDiagSelID Sel) { Visit
(TL.getNextTypeLoc(), Sema::AbstractNone); }
5923
5924 /// Handle all the types we haven't given a more specific
5925 /// implementation for above.
5926 void Check(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
5927 // Every other kind of type that we haven't called out already
5928 // that has an inner type is either (1) sugar or (2) contains that
5929 // inner type in some way as a subobject.
5930 if (TypeLoc Next = TL.getNextTypeLoc())
5931 return Visit(Next, Sel);
5932
5933 // If there's no inner type and we're in a permissive context,
5934 // don't diagnose.
5935 if (Sel == Sema::AbstractNone) return;
5936
5937 // Check whether the type matches the abstract type.
5938 QualType T = TL.getType();
5939 if (T->isArrayType()) {
5940 Sel = Sema::AbstractArrayType;
5941 T = Info.S.Context.getBaseElementType(T);
5942 }
5943 CanQualType CT = T->getCanonicalTypeUnqualified().getUnqualifiedType();
5944 if (CT != Info.AbstractType) return;
5945
5946 // It matched; do some magic.
5947 // FIXME: These should be at most warnings. See P0929R2, CWG1640, CWG1646.
5948 if (Sel == Sema::AbstractArrayType) {
5949 Info.S.Diag(Ctx->getLocation(), diag::err_array_of_abstract_type)
5950 << T << TL.getSourceRange();
5951 } else {
5952 Info.S.Diag(Ctx->getLocation(), diag::err_abstract_type_in_decl)
5953 << Sel << T << TL.getSourceRange();
5954 }
5955 Info.DiagnoseAbstractType();
5956 }
5957};
5958
5959void AbstractUsageInfo::CheckType(const NamedDecl *D, TypeLoc TL,
5960 Sema::AbstractDiagSelID Sel) {
5961 CheckAbstractUsage(*this, D).Visit(TL, Sel);