Bug Summary

File:clang/lib/Sema/SemaDeclCXX.cpp
Warning:line 15404, column 10
Called C++ object pointer is null

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaDeclCXX.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Sema -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/Sema -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/llvm/include -D 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-14/lib/clang/14.0.0/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 -O2 -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 -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-09-04-040900-46481-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/Sema/SemaDeclCXX.cpp

/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/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/EvaluatedExprVisitor.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/AST/RecordLayout.h"
23#include "clang/AST/RecursiveASTVisitor.h"
24#include "clang/AST/StmtVisitor.h"
25#include "clang/AST/TypeLoc.h"
26#include "clang/AST/TypeOrdering.h"
27#include "clang/Basic/AttributeCommonInfo.h"
28#include "clang/Basic/PartialDiagnostic.h"
29#include "clang/Basic/TargetInfo.h"
30#include "clang/Lex/LiteralSupport.h"
31#include "clang/Lex/Preprocessor.h"
32#include "clang/Sema/CXXFieldCollector.h"
33#include "clang/Sema/DeclSpec.h"
34#include "clang/Sema/Initialization.h"
35#include "clang/Sema/Lookup.h"
36#include "clang/Sema/ParsedTemplate.h"
37#include "clang/Sema/Scope.h"
38#include "clang/Sema/ScopeInfo.h"
39#include "clang/Sema/SemaInternal.h"
40#include "clang/Sema/Template.h"
41#include "llvm/ADT/ScopeExit.h"
42#include "llvm/ADT/SmallString.h"
43#include "llvm/ADT/STLExtras.h"
44#include "llvm/ADT/StringExtras.h"
45#include <map>
46#include <set>
47
48using namespace clang;
49
50//===----------------------------------------------------------------------===//
51// CheckDefaultArgumentVisitor
52//===----------------------------------------------------------------------===//
53
54namespace {
55/// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses
56/// the default argument of a parameter to determine whether it
57/// contains any ill-formed subexpressions. For example, this will
58/// diagnose the use of local variables or parameters within the
59/// default argument expression.
60class CheckDefaultArgumentVisitor
61 : public ConstStmtVisitor<CheckDefaultArgumentVisitor, bool> {
62 Sema &S;
63 const Expr *DefaultArg;
64
65public:
66 CheckDefaultArgumentVisitor(Sema &S, const Expr *DefaultArg)
67 : S(S), DefaultArg(DefaultArg) {}
68
69 bool VisitExpr(const Expr *Node);
70 bool VisitDeclRefExpr(const DeclRefExpr *DRE);
71 bool VisitCXXThisExpr(const CXXThisExpr *ThisE);
72 bool VisitLambdaExpr(const LambdaExpr *Lambda);
73 bool VisitPseudoObjectExpr(const PseudoObjectExpr *POE);
74};
75
76/// VisitExpr - Visit all of the children of this expression.
77bool CheckDefaultArgumentVisitor::VisitExpr(const Expr *Node) {
78 bool IsInvalid = false;
79 for (const Stmt *SubStmt : Node->children())
80 IsInvalid |= Visit(SubStmt);
81 return IsInvalid;
82}
83
84/// VisitDeclRefExpr - Visit a reference to a declaration, to
85/// determine whether this declaration can be used in the default
86/// argument expression.
87bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(const DeclRefExpr *DRE) {
88 const NamedDecl *Decl = DRE->getDecl();
89 if (const auto *Param = dyn_cast<ParmVarDecl>(Decl)) {
90 // C++ [dcl.fct.default]p9:
91 // [...] parameters of a function shall not be used in default
92 // argument expressions, even if they are not evaluated. [...]
93 //
94 // C++17 [dcl.fct.default]p9 (by CWG 2082):
95 // [...] A parameter shall not appear as a potentially-evaluated
96 // expression in a default argument. [...]
97 //
98 if (DRE->isNonOdrUse() != NOUR_Unevaluated)
99 return S.Diag(DRE->getBeginLoc(),
100 diag::err_param_default_argument_references_param)
101 << Param->getDeclName() << DefaultArg->getSourceRange();
102 } else if (const auto *VDecl = dyn_cast<VarDecl>(Decl)) {
103 // C++ [dcl.fct.default]p7:
104 // Local variables shall not be used in default argument
105 // expressions.
106 //
107 // C++17 [dcl.fct.default]p7 (by CWG 2082):
108 // A local variable shall not appear as a potentially-evaluated
109 // expression in a default argument.
110 //
111 // C++20 [dcl.fct.default]p7 (DR as part of P0588R1, see also CWG 2346):
112 // Note: A local variable cannot be odr-used (6.3) in a default argument.
113 //
114 if (VDecl->isLocalVarDecl() && !DRE->isNonOdrUse())
115 return S.Diag(DRE->getBeginLoc(),
116 diag::err_param_default_argument_references_local)
117 << VDecl->getDeclName() << DefaultArg->getSourceRange();
118 }
119
120 return false;
121}
122
123/// VisitCXXThisExpr - Visit a C++ "this" expression.
124bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(const CXXThisExpr *ThisE) {
125 // C++ [dcl.fct.default]p8:
126 // The keyword this shall not be used in a default argument of a
127 // member function.
128 return S.Diag(ThisE->getBeginLoc(),
129 diag::err_param_default_argument_references_this)
130 << ThisE->getSourceRange();
131}
132
133bool CheckDefaultArgumentVisitor::VisitPseudoObjectExpr(
134 const PseudoObjectExpr *POE) {
135 bool Invalid = false;
136 for (const Expr *E : POE->semantics()) {
137 // Look through bindings.
138 if (const auto *OVE = dyn_cast<OpaqueValueExpr>(E)) {
139 E = OVE->getSourceExpr();
140 assert(E && "pseudo-object binding without source expression?")(static_cast<void> (0));
141 }
142
143 Invalid |= Visit(E);
144 }
145 return Invalid;
146}
147
148bool CheckDefaultArgumentVisitor::VisitLambdaExpr(const LambdaExpr *Lambda) {
149 // C++11 [expr.lambda.prim]p13:
150 // A lambda-expression appearing in a default argument shall not
151 // implicitly or explicitly capture any entity.
152 if (Lambda->capture_begin() == Lambda->capture_end())
153 return false;
154
155 return S.Diag(Lambda->getBeginLoc(), diag::err_lambda_capture_default_arg);
156}
157} // namespace
158
159void
160Sema::ImplicitExceptionSpecification::CalledDecl(SourceLocation CallLoc,
161 const CXXMethodDecl *Method) {
162 // If we have an MSAny spec already, don't bother.
163 if (!Method || ComputedEST == EST_MSAny)
164 return;
165
166 const FunctionProtoType *Proto
167 = Method->getType()->getAs<FunctionProtoType>();
168 Proto = Self->ResolveExceptionSpec(CallLoc, Proto);
169 if (!Proto)
170 return;
171
172 ExceptionSpecificationType EST = Proto->getExceptionSpecType();
173
174 // If we have a throw-all spec at this point, ignore the function.
175 if (ComputedEST == EST_None)
176 return;
177
178 if (EST == EST_None && Method->hasAttr<NoThrowAttr>())
179 EST = EST_BasicNoexcept;
180
181 switch (EST) {
182 case EST_Unparsed:
183 case EST_Uninstantiated:
184 case EST_Unevaluated:
185 llvm_unreachable("should not see unresolved exception specs here")__builtin_unreachable();
186
187 // If this function can throw any exceptions, make a note of that.
188 case EST_MSAny:
189 case EST_None:
190 // FIXME: Whichever we see last of MSAny and None determines our result.
191 // We should make a consistent, order-independent choice here.
192 ClearExceptions();
193 ComputedEST = EST;
194 return;
195 case EST_NoexceptFalse:
196 ClearExceptions();
197 ComputedEST = EST_None;
198 return;
199 // FIXME: If the call to this decl is using any of its default arguments, we
200 // need to search them for potentially-throwing calls.
201 // If this function has a basic noexcept, it doesn't affect the outcome.
202 case EST_BasicNoexcept:
203 case EST_NoexceptTrue:
204 case EST_NoThrow:
205 return;
206 // If we're still at noexcept(true) and there's a throw() callee,
207 // change to that specification.
208 case EST_DynamicNone:
209 if (ComputedEST == EST_BasicNoexcept)
210 ComputedEST = EST_DynamicNone;
211 return;
212 case EST_DependentNoexcept:
213 llvm_unreachable(__builtin_unreachable()
214 "should not generate implicit declarations for dependent cases")__builtin_unreachable();
215 case EST_Dynamic:
216 break;
217 }
218 assert(EST == EST_Dynamic && "EST case not considered earlier.")(static_cast<void> (0));
219 assert(ComputedEST != EST_None &&(static_cast<void> (0))
220 "Shouldn't collect exceptions when throw-all is guaranteed.")(static_cast<void> (0));
221 ComputedEST = EST_Dynamic;
222 // Record the exceptions in this function's exception specification.
223 for (const auto &E : Proto->exceptions())
224 if (ExceptionsSeen.insert(Self->Context.getCanonicalType(E)).second)
225 Exceptions.push_back(E);
226}
227
228void Sema::ImplicitExceptionSpecification::CalledStmt(Stmt *S) {
229 if (!S || ComputedEST == EST_MSAny)
230 return;
231
232 // FIXME:
233 //
234 // C++0x [except.spec]p14:
235 // [An] implicit exception-specification specifies the type-id T if and
236 // only if T is allowed by the exception-specification of a function directly
237 // invoked by f's implicit definition; f shall allow all exceptions if any
238 // function it directly invokes allows all exceptions, and f shall allow no
239 // exceptions if every function it directly invokes allows no exceptions.
240 //
241 // Note in particular that if an implicit exception-specification is generated
242 // for a function containing a throw-expression, that specification can still
243 // be noexcept(true).
244 //
245 // Note also that 'directly invoked' is not defined in the standard, and there
246 // is no indication that we should only consider potentially-evaluated calls.
247 //
248 // Ultimately we should implement the intent of the standard: the exception
249 // specification should be the set of exceptions which can be thrown by the
250 // implicit definition. For now, we assume that any non-nothrow expression can
251 // throw any exception.
252
253 if (Self->canThrow(S))
254 ComputedEST = EST_None;
255}
256
257ExprResult Sema::ConvertParamDefaultArgument(ParmVarDecl *Param, Expr *Arg,
258 SourceLocation EqualLoc) {
259 if (RequireCompleteType(Param->getLocation(), Param->getType(),
260 diag::err_typecheck_decl_incomplete_type))
261 return true;
262
263 // C++ [dcl.fct.default]p5
264 // A default argument expression is implicitly converted (clause
265 // 4) to the parameter type. The default argument expression has
266 // the same semantic constraints as the initializer expression in
267 // a declaration of a variable of the parameter type, using the
268 // copy-initialization semantics (8.5).
269 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
270 Param);
271 InitializationKind Kind = InitializationKind::CreateCopy(Param->getLocation(),
272 EqualLoc);
273 InitializationSequence InitSeq(*this, Entity, Kind, Arg);
274 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Arg);
275 if (Result.isInvalid())
276 return true;
277 Arg = Result.getAs<Expr>();
278
279 CheckCompletedExpr(Arg, EqualLoc);
280 Arg = MaybeCreateExprWithCleanups(Arg);
281
282 return Arg;
283}
284
285void Sema::SetParamDefaultArgument(ParmVarDecl *Param, Expr *Arg,
286 SourceLocation EqualLoc) {
287 // Add the default argument to the parameter
288 Param->setDefaultArg(Arg);
289
290 // We have already instantiated this parameter; provide each of the
291 // instantiations with the uninstantiated default argument.
292 UnparsedDefaultArgInstantiationsMap::iterator InstPos
293 = UnparsedDefaultArgInstantiations.find(Param);
294 if (InstPos != UnparsedDefaultArgInstantiations.end()) {
295 for (unsigned I = 0, N = InstPos->second.size(); I != N; ++I)
296 InstPos->second[I]->setUninstantiatedDefaultArg(Arg);
297
298 // We're done tracking this parameter's instantiations.
299 UnparsedDefaultArgInstantiations.erase(InstPos);
300 }
301}
302
303/// ActOnParamDefaultArgument - Check whether the default argument
304/// provided for a function parameter is well-formed. If so, attach it
305/// to the parameter declaration.
306void
307Sema::ActOnParamDefaultArgument(Decl *param, SourceLocation EqualLoc,
308 Expr *DefaultArg) {
309 if (!param || !DefaultArg)
310 return;
311
312 ParmVarDecl *Param = cast<ParmVarDecl>(param);
313 UnparsedDefaultArgLocs.erase(Param);
314
315 auto Fail = [&] {
316 Param->setInvalidDecl();
317 Param->setDefaultArg(new (Context) OpaqueValueExpr(
318 EqualLoc, Param->getType().getNonReferenceType(), VK_PRValue));
319 };
320
321 // Default arguments are only permitted in C++
322 if (!getLangOpts().CPlusPlus) {
323 Diag(EqualLoc, diag::err_param_default_argument)
324 << DefaultArg->getSourceRange();
325 return Fail();
326 }
327
328 // Check for unexpanded parameter packs.
329 if (DiagnoseUnexpandedParameterPack(DefaultArg, UPPC_DefaultArgument)) {
330 return Fail();
331 }
332
333 // C++11 [dcl.fct.default]p3
334 // A default argument expression [...] shall not be specified for a
335 // parameter pack.
336 if (Param->isParameterPack()) {
337 Diag(EqualLoc, diag::err_param_default_argument_on_parameter_pack)
338 << DefaultArg->getSourceRange();
339 // Recover by discarding the default argument.
340 Param->setDefaultArg(nullptr);
341 return;
342 }
343
344 ExprResult Result = ConvertParamDefaultArgument(Param, DefaultArg, EqualLoc);
345 if (Result.isInvalid())
346 return Fail();
347
348 DefaultArg = Result.getAs<Expr>();
349
350 // Check that the default argument is well-formed
351 CheckDefaultArgumentVisitor DefaultArgChecker(*this, DefaultArg);
352 if (DefaultArgChecker.Visit(DefaultArg))
353 return Fail();
354
355 SetParamDefaultArgument(Param, DefaultArg, EqualLoc);
356}
357
358/// ActOnParamUnparsedDefaultArgument - We've seen a default
359/// argument for a function parameter, but we can't parse it yet
360/// because we're inside a class definition. Note that this default
361/// argument will be parsed later.
362void Sema::ActOnParamUnparsedDefaultArgument(Decl *param,
363 SourceLocation EqualLoc,
364 SourceLocation ArgLoc) {
365 if (!param)
366 return;
367
368 ParmVarDecl *Param = cast<ParmVarDecl>(param);
369 Param->setUnparsedDefaultArg();
370 UnparsedDefaultArgLocs[Param] = ArgLoc;
371}
372
373/// ActOnParamDefaultArgumentError - Parsing or semantic analysis of
374/// the default argument for the parameter param failed.
375void Sema::ActOnParamDefaultArgumentError(Decl *param,
376 SourceLocation EqualLoc) {
377 if (!param)
378 return;
379
380 ParmVarDecl *Param = cast<ParmVarDecl>(param);
381 Param->setInvalidDecl();
382 UnparsedDefaultArgLocs.erase(Param);
383 Param->setDefaultArg(new (Context) OpaqueValueExpr(
384 EqualLoc, Param->getType().getNonReferenceType(), VK_PRValue));
385}
386
387/// CheckExtraCXXDefaultArguments - Check for any extra default
388/// arguments in the declarator, which is not a function declaration
389/// or definition and therefore is not permitted to have default
390/// arguments. This routine should be invoked for every declarator
391/// that is not a function declaration or definition.
392void Sema::CheckExtraCXXDefaultArguments(Declarator &D) {
393 // C++ [dcl.fct.default]p3
394 // A default argument expression shall be specified only in the
395 // parameter-declaration-clause of a function declaration or in a
396 // template-parameter (14.1). It shall not be specified for a
397 // parameter pack. If it is specified in a
398 // parameter-declaration-clause, it shall not occur within a
399 // declarator or abstract-declarator of a parameter-declaration.
400 bool MightBeFunction = D.isFunctionDeclarationContext();
401 for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
402 DeclaratorChunk &chunk = D.getTypeObject(i);
403 if (chunk.Kind == DeclaratorChunk::Function) {
404 if (MightBeFunction) {
405 // This is a function declaration. It can have default arguments, but
406 // keep looking in case its return type is a function type with default
407 // arguments.
408 MightBeFunction = false;
409 continue;
410 }
411 for (unsigned argIdx = 0, e = chunk.Fun.NumParams; argIdx != e;
412 ++argIdx) {
413 ParmVarDecl *Param = cast<ParmVarDecl>(chunk.Fun.Params[argIdx].Param);
414 if (Param->hasUnparsedDefaultArg()) {
415 std::unique_ptr<CachedTokens> Toks =
416 std::move(chunk.Fun.Params[argIdx].DefaultArgTokens);
417 SourceRange SR;
418 if (Toks->size() > 1)
419 SR = SourceRange((*Toks)[1].getLocation(),
420 Toks->back().getLocation());
421 else
422 SR = UnparsedDefaultArgLocs[Param];
423 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
424 << SR;
425 } else if (Param->getDefaultArg()) {
426 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
427 << Param->getDefaultArg()->getSourceRange();
428 Param->setDefaultArg(nullptr);
429 }
430 }
431 } else if (chunk.Kind != DeclaratorChunk::Paren) {
432 MightBeFunction = false;
433 }
434 }
435}
436
437static bool functionDeclHasDefaultArgument(const FunctionDecl *FD) {
438 return std::any_of(FD->param_begin(), FD->param_end(), [](ParmVarDecl *P) {
439 return P->hasDefaultArg() && !P->hasInheritedDefaultArg();
440 });
441}
442
443/// MergeCXXFunctionDecl - Merge two declarations of the same C++
444/// function, once we already know that they have the same
445/// type. Subroutine of MergeFunctionDecl. Returns true if there was an
446/// error, false otherwise.
447bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old,
448 Scope *S) {
449 bool Invalid = false;
450
451 // The declaration context corresponding to the scope is the semantic
452 // parent, unless this is a local function declaration, in which case
453 // it is that surrounding function.
454 DeclContext *ScopeDC = New->isLocalExternDecl()
455 ? New->getLexicalDeclContext()
456 : New->getDeclContext();
457
458 // Find the previous declaration for the purpose of default arguments.
459 FunctionDecl *PrevForDefaultArgs = Old;
460 for (/**/; PrevForDefaultArgs;
461 // Don't bother looking back past the latest decl if this is a local
462 // extern declaration; nothing else could work.
463 PrevForDefaultArgs = New->isLocalExternDecl()
464 ? nullptr
465 : PrevForDefaultArgs->getPreviousDecl()) {
466 // Ignore hidden declarations.
467 if (!LookupResult::isVisible(*this, PrevForDefaultArgs))
468 continue;
469
470 if (S && !isDeclInScope(PrevForDefaultArgs, ScopeDC, S) &&
471 !New->isCXXClassMember()) {
472 // Ignore default arguments of old decl if they are not in
473 // the same scope and this is not an out-of-line definition of
474 // a member function.
475 continue;
476 }
477
478 if (PrevForDefaultArgs->isLocalExternDecl() != New->isLocalExternDecl()) {
479 // If only one of these is a local function declaration, then they are
480 // declared in different scopes, even though isDeclInScope may think
481 // they're in the same scope. (If both are local, the scope check is
482 // sufficient, and if neither is local, then they are in the same scope.)
483 continue;
484 }
485
486 // We found the right previous declaration.
487 break;
488 }
489
490 // C++ [dcl.fct.default]p4:
491 // For non-template functions, default arguments can be added in
492 // later declarations of a function in the same
493 // scope. Declarations in different scopes have completely
494 // distinct sets of default arguments. That is, declarations in
495 // inner scopes do not acquire default arguments from
496 // declarations in outer scopes, and vice versa. In a given
497 // function declaration, all parameters subsequent to a
498 // parameter with a default argument shall have default
499 // arguments supplied in this or previous declarations. A
500 // default argument shall not be redefined by a later
501 // declaration (not even to the same value).
502 //
503 // C++ [dcl.fct.default]p6:
504 // Except for member functions of class templates, the default arguments
505 // in a member function definition that appears outside of the class
506 // definition are added to the set of default arguments provided by the
507 // member function declaration in the class definition.
508 for (unsigned p = 0, NumParams = PrevForDefaultArgs
509 ? PrevForDefaultArgs->getNumParams()
510 : 0;
511 p < NumParams; ++p) {
512 ParmVarDecl *OldParam = PrevForDefaultArgs->getParamDecl(p);
513 ParmVarDecl *NewParam = New->getParamDecl(p);
514
515 bool OldParamHasDfl = OldParam ? OldParam->hasDefaultArg() : false;
516 bool NewParamHasDfl = NewParam->hasDefaultArg();
517
518 if (OldParamHasDfl && NewParamHasDfl) {
519 unsigned DiagDefaultParamID =
520 diag::err_param_default_argument_redefinition;
521
522 // MSVC accepts that default parameters be redefined for member functions
523 // of template class. The new default parameter's value is ignored.
524 Invalid = true;
525 if (getLangOpts().MicrosoftExt) {
526 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(New);
527 if (MD && MD->getParent()->getDescribedClassTemplate()) {
528 // Merge the old default argument into the new parameter.
529 NewParam->setHasInheritedDefaultArg();
530 if (OldParam->hasUninstantiatedDefaultArg())
531 NewParam->setUninstantiatedDefaultArg(
532 OldParam->getUninstantiatedDefaultArg());
533 else
534 NewParam->setDefaultArg(OldParam->getInit());
535 DiagDefaultParamID = diag::ext_param_default_argument_redefinition;
536 Invalid = false;
537 }
538 }
539
540 // FIXME: If we knew where the '=' was, we could easily provide a fix-it
541 // hint here. Alternatively, we could walk the type-source information
542 // for NewParam to find the last source location in the type... but it
543 // isn't worth the effort right now. This is the kind of test case that
544 // is hard to get right:
545 // int f(int);
546 // void g(int (*fp)(int) = f);
547 // void g(int (*fp)(int) = &f);
548 Diag(NewParam->getLocation(), DiagDefaultParamID)
549 << NewParam->getDefaultArgRange();
550
551 // Look for the function declaration where the default argument was
552 // actually written, which may be a declaration prior to Old.
553 for (auto Older = PrevForDefaultArgs;
554 OldParam->hasInheritedDefaultArg(); /**/) {
555 Older = Older->getPreviousDecl();
556 OldParam = Older->getParamDecl(p);
557 }
558
559 Diag(OldParam->getLocation(), diag::note_previous_definition)
560 << OldParam->getDefaultArgRange();
561 } else if (OldParamHasDfl) {
562 // Merge the old default argument into the new parameter unless the new
563 // function is a friend declaration in a template class. In the latter
564 // case the default arguments will be inherited when the friend
565 // declaration will be instantiated.
566 if (New->getFriendObjectKind() == Decl::FOK_None ||
567 !New->getLexicalDeclContext()->isDependentContext()) {
568 // It's important to use getInit() here; getDefaultArg()
569 // strips off any top-level ExprWithCleanups.
570 NewParam->setHasInheritedDefaultArg();
571 if (OldParam->hasUnparsedDefaultArg())
572 NewParam->setUnparsedDefaultArg();
573 else if (OldParam->hasUninstantiatedDefaultArg())
574 NewParam->setUninstantiatedDefaultArg(
575 OldParam->getUninstantiatedDefaultArg());
576 else
577 NewParam->setDefaultArg(OldParam->getInit());
578 }
579 } else if (NewParamHasDfl) {
580 if (New->getDescribedFunctionTemplate()) {
581 // Paragraph 4, quoted above, only applies to non-template functions.
582 Diag(NewParam->getLocation(),
583 diag::err_param_default_argument_template_redecl)
584 << NewParam->getDefaultArgRange();
585 Diag(PrevForDefaultArgs->getLocation(),
586 diag::note_template_prev_declaration)
587 << false;
588 } else if (New->getTemplateSpecializationKind()
589 != TSK_ImplicitInstantiation &&
590 New->getTemplateSpecializationKind() != TSK_Undeclared) {
591 // C++ [temp.expr.spec]p21:
592 // Default function arguments shall not be specified in a declaration
593 // or a definition for one of the following explicit specializations:
594 // - the explicit specialization of a function template;
595 // - the explicit specialization of a member function template;
596 // - the explicit specialization of a member function of a class
597 // template where the class template specialization to which the
598 // member function specialization belongs is implicitly
599 // instantiated.
600 Diag(NewParam->getLocation(), diag::err_template_spec_default_arg)
601 << (New->getTemplateSpecializationKind() ==TSK_ExplicitSpecialization)
602 << New->getDeclName()
603 << NewParam->getDefaultArgRange();
604 } else if (New->getDeclContext()->isDependentContext()) {
605 // C++ [dcl.fct.default]p6 (DR217):
606 // Default arguments for a member function of a class template shall
607 // be specified on the initial declaration of the member function
608 // within the class template.
609 //
610 // Reading the tea leaves a bit in DR217 and its reference to DR205
611 // leads me to the conclusion that one cannot add default function
612 // arguments for an out-of-line definition of a member function of a
613 // dependent type.
614 int WhichKind = 2;
615 if (CXXRecordDecl *Record
616 = dyn_cast<CXXRecordDecl>(New->getDeclContext())) {
617 if (Record->getDescribedClassTemplate())
618 WhichKind = 0;
619 else if (isa<ClassTemplatePartialSpecializationDecl>(Record))
620 WhichKind = 1;
621 else
622 WhichKind = 2;
623 }
624
625 Diag(NewParam->getLocation(),
626 diag::err_param_default_argument_member_template_redecl)
627 << WhichKind
628 << NewParam->getDefaultArgRange();
629 }
630 }
631 }
632
633 // DR1344: If a default argument is added outside a class definition and that
634 // default argument makes the function a special member function, the program
635 // is ill-formed. This can only happen for constructors.
636 if (isa<CXXConstructorDecl>(New) &&
637 New->getMinRequiredArguments() < Old->getMinRequiredArguments()) {
638 CXXSpecialMember NewSM = getSpecialMember(cast<CXXMethodDecl>(New)),
639 OldSM = getSpecialMember(cast<CXXMethodDecl>(Old));
640 if (NewSM != OldSM) {
641 ParmVarDecl *NewParam = New->getParamDecl(New->getMinRequiredArguments());
642 assert(NewParam->hasDefaultArg())(static_cast<void> (0));
643 Diag(NewParam->getLocation(), diag::err_default_arg_makes_ctor_special)
644 << NewParam->getDefaultArgRange() << NewSM;
645 Diag(Old->getLocation(), diag::note_previous_declaration);
646 }
647 }
648
649 const FunctionDecl *Def;
650 // C++11 [dcl.constexpr]p1: If any declaration of a function or function
651 // template has a constexpr specifier then all its declarations shall
652 // contain the constexpr specifier.
653 if (New->getConstexprKind() != Old->getConstexprKind()) {
654 Diag(New->getLocation(), diag::err_constexpr_redecl_mismatch)
655 << New << static_cast<int>(New->getConstexprKind())
656 << static_cast<int>(Old->getConstexprKind());
657 Diag(Old->getLocation(), diag::note_previous_declaration);
658 Invalid = true;
659 } else if (!Old->getMostRecentDecl()->isInlined() && New->isInlined() &&
660 Old->isDefined(Def) &&
661 // If a friend function is inlined but does not have 'inline'
662 // specifier, it is a definition. Do not report attribute conflict
663 // in this case, redefinition will be diagnosed later.
664 (New->isInlineSpecified() ||
665 New->getFriendObjectKind() == Decl::FOK_None)) {
666 // C++11 [dcl.fcn.spec]p4:
667 // If the definition of a function appears in a translation unit before its
668 // first declaration as inline, the program is ill-formed.
669 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
670 Diag(Def->getLocation(), diag::note_previous_definition);
671 Invalid = true;
672 }
673
674 // C++17 [temp.deduct.guide]p3:
675 // Two deduction guide declarations in the same translation unit
676 // for the same class template shall not have equivalent
677 // parameter-declaration-clauses.
678 if (isa<CXXDeductionGuideDecl>(New) &&
679 !New->isFunctionTemplateSpecialization() && isVisible(Old)) {
680 Diag(New->getLocation(), diag::err_deduction_guide_redeclared);
681 Diag(Old->getLocation(), diag::note_previous_declaration);
682 }
683
684 // C++11 [dcl.fct.default]p4: If a friend declaration specifies a default
685 // argument expression, that declaration shall be a definition and shall be
686 // the only declaration of the function or function template in the
687 // translation unit.
688 if (Old->getFriendObjectKind() == Decl::FOK_Undeclared &&
689 functionDeclHasDefaultArgument(Old)) {
690 Diag(New->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
691 Diag(Old->getLocation(), diag::note_previous_declaration);
692 Invalid = true;
693 }
694
695 // C++11 [temp.friend]p4 (DR329):
696 // When a function is defined in a friend function declaration in a class
697 // template, the function is instantiated when the function is odr-used.
698 // The same restrictions on multiple declarations and definitions that
699 // apply to non-template function declarations and definitions also apply
700 // to these implicit definitions.
701 const FunctionDecl *OldDefinition = nullptr;
702 if (New->isThisDeclarationInstantiatedFromAFriendDefinition() &&
703 Old->isDefined(OldDefinition, true))
704 CheckForFunctionRedefinition(New, OldDefinition);
705
706 return Invalid;
707}
708
709NamedDecl *
710Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
711 MultiTemplateParamsArg TemplateParamLists) {
712 assert(D.isDecompositionDeclarator())(static_cast<void> (0));
713 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
714
715 // The syntax only allows a decomposition declarator as a simple-declaration,
716 // a for-range-declaration, or a condition in Clang, but we parse it in more
717 // cases than that.
718 if (!D.mayHaveDecompositionDeclarator()) {
719 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
720 << Decomp.getSourceRange();
721 return nullptr;
722 }
723
724 if (!TemplateParamLists.empty()) {
725 // FIXME: There's no rule against this, but there are also no rules that
726 // would actually make it usable, so we reject it for now.
727 Diag(TemplateParamLists.front()->getTemplateLoc(),
728 diag::err_decomp_decl_template);
729 return nullptr;
730 }
731
732 Diag(Decomp.getLSquareLoc(),
733 !getLangOpts().CPlusPlus17
734 ? diag::ext_decomp_decl
735 : D.getContext() == DeclaratorContext::Condition
736 ? diag::ext_decomp_decl_cond
737 : diag::warn_cxx14_compat_decomp_decl)
738 << Decomp.getSourceRange();
739
740 // The semantic context is always just the current context.
741 DeclContext *const DC = CurContext;
742
743 // C++17 [dcl.dcl]/8:
744 // The decl-specifier-seq shall contain only the type-specifier auto
745 // and cv-qualifiers.
746 // C++2a [dcl.dcl]/8:
747 // If decl-specifier-seq contains any decl-specifier other than static,
748 // thread_local, auto, or cv-qualifiers, the program is ill-formed.
749 auto &DS = D.getDeclSpec();
750 {
751 SmallVector<StringRef, 8> BadSpecifiers;
752 SmallVector<SourceLocation, 8> BadSpecifierLocs;
753 SmallVector<StringRef, 8> CPlusPlus20Specifiers;
754 SmallVector<SourceLocation, 8> CPlusPlus20SpecifierLocs;
755 if (auto SCS = DS.getStorageClassSpec()) {
756 if (SCS == DeclSpec::SCS_static) {
757 CPlusPlus20Specifiers.push_back(DeclSpec::getSpecifierName(SCS));
758 CPlusPlus20SpecifierLocs.push_back(DS.getStorageClassSpecLoc());
759 } else {
760 BadSpecifiers.push_back(DeclSpec::getSpecifierName(SCS));
761 BadSpecifierLocs.push_back(DS.getStorageClassSpecLoc());
762 }
763 }
764 if (auto TSCS = DS.getThreadStorageClassSpec()) {
765 CPlusPlus20Specifiers.push_back(DeclSpec::getSpecifierName(TSCS));
766 CPlusPlus20SpecifierLocs.push_back(DS.getThreadStorageClassSpecLoc());
767 }
768 if (DS.hasConstexprSpecifier()) {
769 BadSpecifiers.push_back(
770 DeclSpec::getSpecifierName(DS.getConstexprSpecifier()));
771 BadSpecifierLocs.push_back(DS.getConstexprSpecLoc());
772 }
773 if (DS.isInlineSpecified()) {
774 BadSpecifiers.push_back("inline");
775 BadSpecifierLocs.push_back(DS.getInlineSpecLoc());
776 }
777 if (!BadSpecifiers.empty()) {
778 auto &&Err = Diag(BadSpecifierLocs.front(), diag::err_decomp_decl_spec);
779 Err << (int)BadSpecifiers.size()
780 << llvm::join(BadSpecifiers.begin(), BadSpecifiers.end(), " ");
781 // Don't add FixItHints to remove the specifiers; we do still respect
782 // them when building the underlying variable.
783 for (auto Loc : BadSpecifierLocs)
784 Err << SourceRange(Loc, Loc);
785 } else if (!CPlusPlus20Specifiers.empty()) {
786 auto &&Warn = Diag(CPlusPlus20SpecifierLocs.front(),
787 getLangOpts().CPlusPlus20
788 ? diag::warn_cxx17_compat_decomp_decl_spec
789 : diag::ext_decomp_decl_spec);
790 Warn << (int)CPlusPlus20Specifiers.size()
791 << llvm::join(CPlusPlus20Specifiers.begin(),
792 CPlusPlus20Specifiers.end(), " ");
793 for (auto Loc : CPlusPlus20SpecifierLocs)
794 Warn << SourceRange(Loc, Loc);
795 }
796 // We can't recover from it being declared as a typedef.
797 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
798 return nullptr;
799 }
800
801 // C++2a [dcl.struct.bind]p1:
802 // A cv that includes volatile is deprecated
803 if ((DS.getTypeQualifiers() & DeclSpec::TQ_volatile) &&
804 getLangOpts().CPlusPlus20)
805 Diag(DS.getVolatileSpecLoc(),
806 diag::warn_deprecated_volatile_structured_binding);
807
808 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
809 QualType R = TInfo->getType();
810
811 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
812 UPPC_DeclarationType))
813 D.setInvalidType();
814
815 // The syntax only allows a single ref-qualifier prior to the decomposition
816 // declarator. No other declarator chunks are permitted. Also check the type
817 // specifier here.
818 if (DS.getTypeSpecType() != DeclSpec::TST_auto ||
819 D.hasGroupingParens() || D.getNumTypeObjects() > 1 ||
820 (D.getNumTypeObjects() == 1 &&
821 D.getTypeObject(0).Kind != DeclaratorChunk::Reference)) {
822 Diag(Decomp.getLSquareLoc(),
823 (D.hasGroupingParens() ||
824 (D.getNumTypeObjects() &&
825 D.getTypeObject(0).Kind == DeclaratorChunk::Paren))
826 ? diag::err_decomp_decl_parens
827 : diag::err_decomp_decl_type)
828 << R;
829
830 // In most cases, there's no actual problem with an explicitly-specified
831 // type, but a function type won't work here, and ActOnVariableDeclarator
832 // shouldn't be called for such a type.
833 if (R->isFunctionType())
834 D.setInvalidType();
835 }
836
837 // Build the BindingDecls.
838 SmallVector<BindingDecl*, 8> Bindings;
839
840 // Build the BindingDecls.
841 for (auto &B : D.getDecompositionDeclarator().bindings()) {
842 // Check for name conflicts.
843 DeclarationNameInfo NameInfo(B.Name, B.NameLoc);
844 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
845 ForVisibleRedeclaration);
846 LookupName(Previous, S,
847 /*CreateBuiltins*/DC->getRedeclContext()->isTranslationUnit());
848
849 // It's not permitted to shadow a template parameter name.
850 if (Previous.isSingleResult() &&
851 Previous.getFoundDecl()->isTemplateParameter()) {
852 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
853 Previous.getFoundDecl());
854 Previous.clear();
855 }
856
857 auto *BD = BindingDecl::Create(Context, DC, B.NameLoc, B.Name);
858
859 // Find the shadowed declaration before filtering for scope.
860 NamedDecl *ShadowedDecl = D.getCXXScopeSpec().isEmpty()
861 ? getShadowedDeclaration(BD, Previous)
862 : nullptr;
863
864 bool ConsiderLinkage = DC->isFunctionOrMethod() &&
865 DS.getStorageClassSpec() == DeclSpec::SCS_extern;
866 FilterLookupForScope(Previous, DC, S, ConsiderLinkage,
867 /*AllowInlineNamespace*/false);
868
869 if (!Previous.empty()) {
870 auto *Old = Previous.getRepresentativeDecl();
871 Diag(B.NameLoc, diag::err_redefinition) << B.Name;
872 Diag(Old->getLocation(), diag::note_previous_definition);
873 } else if (ShadowedDecl && !D.isRedeclaration()) {
874 CheckShadow(BD, ShadowedDecl, Previous);
875 }
876 PushOnScopeChains(BD, S, true);
877 Bindings.push_back(BD);
878 ParsingInitForAutoVars.insert(BD);
879 }
880
881 // There are no prior lookup results for the variable itself, because it
882 // is unnamed.
883 DeclarationNameInfo NameInfo((IdentifierInfo *)nullptr,
884 Decomp.getLSquareLoc());
885 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
886 ForVisibleRedeclaration);
887
888 // Build the variable that holds the non-decomposed object.
889 bool AddToScope = true;
890 NamedDecl *New =
891 ActOnVariableDeclarator(S, D, DC, TInfo, Previous,
892 MultiTemplateParamsArg(), AddToScope, Bindings);
893 if (AddToScope) {
894 S->AddDecl(New);
895 CurContext->addHiddenDecl(New);
896 }
897
898 if (isInOpenMPDeclareTargetContext())
899 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
900
901 return New;
902}
903
904static bool checkSimpleDecomposition(
905 Sema &S, ArrayRef<BindingDecl *> Bindings, ValueDecl *Src,
906 QualType DecompType, const llvm::APSInt &NumElems, QualType ElemType,
907 llvm::function_ref<ExprResult(SourceLocation, Expr *, unsigned)> GetInit) {
908 if ((int64_t)Bindings.size() != NumElems) {
909 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
910 << DecompType << (unsigned)Bindings.size()
911 << (unsigned)NumElems.getLimitedValue(UINT_MAX(2147483647 *2U +1U))
912 << toString(NumElems, 10) << (NumElems < Bindings.size());
913 return true;
914 }
915
916 unsigned I = 0;
917 for (auto *B : Bindings) {
918 SourceLocation Loc = B->getLocation();
919 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
920 if (E.isInvalid())
921 return true;
922 E = GetInit(Loc, E.get(), I++);
923 if (E.isInvalid())
924 return true;
925 B->setBinding(ElemType, E.get());
926 }
927
928 return false;
929}
930
931static bool checkArrayLikeDecomposition(Sema &S,
932 ArrayRef<BindingDecl *> Bindings,
933 ValueDecl *Src, QualType DecompType,
934 const llvm::APSInt &NumElems,
935 QualType ElemType) {
936 return checkSimpleDecomposition(
937 S, Bindings, Src, DecompType, NumElems, ElemType,
938 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
939 ExprResult E = S.ActOnIntegerConstant(Loc, I);
940 if (E.isInvalid())
941 return ExprError();
942 return S.CreateBuiltinArraySubscriptExpr(Base, Loc, E.get(), Loc);
943 });
944}
945
946static bool checkArrayDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
947 ValueDecl *Src, QualType DecompType,
948 const ConstantArrayType *CAT) {
949 return checkArrayLikeDecomposition(S, Bindings, Src, DecompType,
950 llvm::APSInt(CAT->getSize()),
951 CAT->getElementType());
952}
953
954static bool checkVectorDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
955 ValueDecl *Src, QualType DecompType,
956 const VectorType *VT) {
957 return checkArrayLikeDecomposition(
958 S, Bindings, Src, DecompType, llvm::APSInt::get(VT->getNumElements()),
959 S.Context.getQualifiedType(VT->getElementType(),
960 DecompType.getQualifiers()));
961}
962
963static bool checkComplexDecomposition(Sema &S,
964 ArrayRef<BindingDecl *> Bindings,
965 ValueDecl *Src, QualType DecompType,
966 const ComplexType *CT) {
967 return checkSimpleDecomposition(
968 S, Bindings, Src, DecompType, llvm::APSInt::get(2),
969 S.Context.getQualifiedType(CT->getElementType(),
970 DecompType.getQualifiers()),
971 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
972 return S.CreateBuiltinUnaryOp(Loc, I ? UO_Imag : UO_Real, Base);
973 });
974}
975
976static std::string printTemplateArgs(const PrintingPolicy &PrintingPolicy,
977 TemplateArgumentListInfo &Args,
978 const TemplateParameterList *Params) {
979 SmallString<128> SS;
980 llvm::raw_svector_ostream OS(SS);
981 bool First = true;
982 unsigned I = 0;
983 for (auto &Arg : Args.arguments()) {
984 if (!First)
985 OS << ", ";
986 Arg.getArgument().print(
987 PrintingPolicy, OS,
988 TemplateParameterList::shouldIncludeTypeForArgument(Params, I));
989 First = false;
990 I++;
991 }
992 return std::string(OS.str());
993}
994
995static bool lookupStdTypeTraitMember(Sema &S, LookupResult &TraitMemberLookup,
996 SourceLocation Loc, StringRef Trait,
997 TemplateArgumentListInfo &Args,
998 unsigned DiagID) {
999 auto DiagnoseMissing = [&] {
1000 if (DiagID)
1001 S.Diag(Loc, DiagID) << printTemplateArgs(S.Context.getPrintingPolicy(),
1002 Args, /*Params*/ nullptr);
1003 return true;
1004 };
1005
1006 // FIXME: Factor out duplication with lookupPromiseType in SemaCoroutine.
1007 NamespaceDecl *Std = S.getStdNamespace();
1008 if (!Std)
1009 return DiagnoseMissing();
1010
1011 // Look up the trait itself, within namespace std. We can diagnose various
1012 // problems with this lookup even if we've been asked to not diagnose a
1013 // missing specialization, because this can only fail if the user has been
1014 // declaring their own names in namespace std or we don't support the
1015 // standard library implementation in use.
1016 LookupResult Result(S, &S.PP.getIdentifierTable().get(Trait),
1017 Loc, Sema::LookupOrdinaryName);
1018 if (!S.LookupQualifiedName(Result, Std))
1019 return DiagnoseMissing();
1020 if (Result.isAmbiguous())
1021 return true;
1022
1023 ClassTemplateDecl *TraitTD = Result.getAsSingle<ClassTemplateDecl>();
1024 if (!TraitTD) {
1025 Result.suppressDiagnostics();
1026 NamedDecl *Found = *Result.begin();
1027 S.Diag(Loc, diag::err_std_type_trait_not_class_template) << Trait;
1028 S.Diag(Found->getLocation(), diag::note_declared_at);
1029 return true;
1030 }
1031
1032 // Build the template-id.
1033 QualType TraitTy = S.CheckTemplateIdType(TemplateName(TraitTD), Loc, Args);
1034 if (TraitTy.isNull())
1035 return true;
1036 if (!S.isCompleteType(Loc, TraitTy)) {
1037 if (DiagID)
1038 S.RequireCompleteType(
1039 Loc, TraitTy, DiagID,
1040 printTemplateArgs(S.Context.getPrintingPolicy(), Args,
1041 TraitTD->getTemplateParameters()));
1042 return true;
1043 }
1044
1045 CXXRecordDecl *RD = TraitTy->getAsCXXRecordDecl();
1046 assert(RD && "specialization of class template is not a class?")(static_cast<void> (0));
1047
1048 // Look up the member of the trait type.
1049 S.LookupQualifiedName(TraitMemberLookup, RD);
1050 return TraitMemberLookup.isAmbiguous();
1051}
1052
1053static TemplateArgumentLoc
1054getTrivialIntegralTemplateArgument(Sema &S, SourceLocation Loc, QualType T,
1055 uint64_t I) {
1056 TemplateArgument Arg(S.Context, S.Context.MakeIntValue(I, T), T);
1057 return S.getTrivialTemplateArgumentLoc(Arg, T, Loc);
1058}
1059
1060static TemplateArgumentLoc
1061getTrivialTypeTemplateArgument(Sema &S, SourceLocation Loc, QualType T) {
1062 return S.getTrivialTemplateArgumentLoc(TemplateArgument(T), QualType(), Loc);
1063}
1064
1065namespace { enum class IsTupleLike { TupleLike, NotTupleLike, Error }; }
1066
1067static IsTupleLike isTupleLike(Sema &S, SourceLocation Loc, QualType T,
1068 llvm::APSInt &Size) {
1069 EnterExpressionEvaluationContext ContextRAII(
1070 S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
1071
1072 DeclarationName Value = S.PP.getIdentifierInfo("value");
1073 LookupResult R(S, Value, Loc, Sema::LookupOrdinaryName);
1074
1075 // Form template argument list for tuple_size<T>.
1076 TemplateArgumentListInfo Args(Loc, Loc);
1077 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
1078
1079 // If there's no tuple_size specialization or the lookup of 'value' is empty,
1080 // it's not tuple-like.
1081 if (lookupStdTypeTraitMember(S, R, Loc, "tuple_size", Args, /*DiagID*/ 0) ||
1082 R.empty())
1083 return IsTupleLike::NotTupleLike;
1084
1085 // If we get this far, we've committed to the tuple interpretation, but
1086 // we can still fail if there actually isn't a usable ::value.
1087
1088 struct ICEDiagnoser : Sema::VerifyICEDiagnoser {
1089 LookupResult &R;
1090 TemplateArgumentListInfo &Args;
1091 ICEDiagnoser(LookupResult &R, TemplateArgumentListInfo &Args)
1092 : R(R), Args(Args) {}
1093 Sema::SemaDiagnosticBuilder diagnoseNotICE(Sema &S,
1094 SourceLocation Loc) override {
1095 return S.Diag(Loc, diag::err_decomp_decl_std_tuple_size_not_constant)
1096 << printTemplateArgs(S.Context.getPrintingPolicy(), Args,
1097 /*Params*/ nullptr);
1098 }
1099 } Diagnoser(R, Args);
1100
1101 ExprResult E =
1102 S.BuildDeclarationNameExpr(CXXScopeSpec(), R, /*NeedsADL*/false);
1103 if (E.isInvalid())
1104 return IsTupleLike::Error;
1105
1106 E = S.VerifyIntegerConstantExpression(E.get(), &Size, Diagnoser);
1107 if (E.isInvalid())
1108 return IsTupleLike::Error;
1109
1110 return IsTupleLike::TupleLike;
1111}
1112
1113/// \return std::tuple_element<I, T>::type.
1114static QualType getTupleLikeElementType(Sema &S, SourceLocation Loc,
1115 unsigned I, QualType T) {
1116 // Form template argument list for tuple_element<I, T>.
1117 TemplateArgumentListInfo Args(Loc, Loc);
1118 Args.addArgument(
1119 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1120 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
1121
1122 DeclarationName TypeDN = S.PP.getIdentifierInfo("type");
1123 LookupResult R(S, TypeDN, Loc, Sema::LookupOrdinaryName);
1124 if (lookupStdTypeTraitMember(
1125 S, R, Loc, "tuple_element", Args,
1126 diag::err_decomp_decl_std_tuple_element_not_specialized))
1127 return QualType();
1128
1129 auto *TD = R.getAsSingle<TypeDecl>();
1130 if (!TD) {
1131 R.suppressDiagnostics();
1132 S.Diag(Loc, diag::err_decomp_decl_std_tuple_element_not_specialized)
1133 << printTemplateArgs(S.Context.getPrintingPolicy(), Args,
1134 /*Params*/ nullptr);
1135 if (!R.empty())
1136 S.Diag(R.getRepresentativeDecl()->getLocation(), diag::note_declared_at);
1137 return QualType();
1138 }
1139
1140 return S.Context.getTypeDeclType(TD);
1141}
1142
1143namespace {
1144struct InitializingBinding {
1145 Sema &S;
1146 InitializingBinding(Sema &S, BindingDecl *BD) : S(S) {
1147 Sema::CodeSynthesisContext Ctx;
1148 Ctx.Kind = Sema::CodeSynthesisContext::InitializingStructuredBinding;
1149 Ctx.PointOfInstantiation = BD->getLocation();
1150 Ctx.Entity = BD;
1151 S.pushCodeSynthesisContext(Ctx);
1152 }
1153 ~InitializingBinding() {
1154 S.popCodeSynthesisContext();
1155 }
1156};
1157}
1158
1159static bool checkTupleLikeDecomposition(Sema &S,
1160 ArrayRef<BindingDecl *> Bindings,
1161 VarDecl *Src, QualType DecompType,
1162 const llvm::APSInt &TupleSize) {
1163 if ((int64_t)Bindings.size() != TupleSize) {
1164 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1165 << DecompType << (unsigned)Bindings.size()
1166 << (unsigned)TupleSize.getLimitedValue(UINT_MAX(2147483647 *2U +1U))
1167 << toString(TupleSize, 10) << (TupleSize < Bindings.size());
1168 return true;
1169 }
1170
1171 if (Bindings.empty())
1172 return false;
1173
1174 DeclarationName GetDN = S.PP.getIdentifierInfo("get");
1175
1176 // [dcl.decomp]p3:
1177 // The unqualified-id get is looked up in the scope of E by class member
1178 // access lookup ...
1179 LookupResult MemberGet(S, GetDN, Src->getLocation(), Sema::LookupMemberName);
1180 bool UseMemberGet = false;
1181 if (S.isCompleteType(Src->getLocation(), DecompType)) {
1182 if (auto *RD = DecompType->getAsCXXRecordDecl())
1183 S.LookupQualifiedName(MemberGet, RD);
1184 if (MemberGet.isAmbiguous())
1185 return true;
1186 // ... and if that finds at least one declaration that is a function
1187 // template whose first template parameter is a non-type parameter ...
1188 for (NamedDecl *D : MemberGet) {
1189 if (FunctionTemplateDecl *FTD =
1190 dyn_cast<FunctionTemplateDecl>(D->getUnderlyingDecl())) {
1191 TemplateParameterList *TPL = FTD->getTemplateParameters();
1192 if (TPL->size() != 0 &&
1193 isa<NonTypeTemplateParmDecl>(TPL->getParam(0))) {
1194 // ... the initializer is e.get<i>().
1195 UseMemberGet = true;
1196 break;
1197 }
1198 }
1199 }
1200 }
1201
1202 unsigned I = 0;
1203 for (auto *B : Bindings) {
1204 InitializingBinding InitContext(S, B);
1205 SourceLocation Loc = B->getLocation();
1206
1207 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1208 if (E.isInvalid())
1209 return true;
1210
1211 // e is an lvalue if the type of the entity is an lvalue reference and
1212 // an xvalue otherwise
1213 if (!Src->getType()->isLValueReferenceType())
1214 E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), CK_NoOp,
1215 E.get(), nullptr, VK_XValue,
1216 FPOptionsOverride());
1217
1218 TemplateArgumentListInfo Args(Loc, Loc);
1219 Args.addArgument(
1220 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1221
1222 if (UseMemberGet) {
1223 // if [lookup of member get] finds at least one declaration, the
1224 // initializer is e.get<i-1>().
1225 E = S.BuildMemberReferenceExpr(E.get(), DecompType, Loc, false,
1226 CXXScopeSpec(), SourceLocation(), nullptr,
1227 MemberGet, &Args, nullptr);
1228 if (E.isInvalid())
1229 return true;
1230
1231 E = S.BuildCallExpr(nullptr, E.get(), Loc, None, Loc);
1232 } else {
1233 // Otherwise, the initializer is get<i-1>(e), where get is looked up
1234 // in the associated namespaces.
1235 Expr *Get = UnresolvedLookupExpr::Create(
1236 S.Context, nullptr, NestedNameSpecifierLoc(), SourceLocation(),
1237 DeclarationNameInfo(GetDN, Loc), /*RequiresADL*/true, &Args,
1238 UnresolvedSetIterator(), UnresolvedSetIterator());
1239
1240 Expr *Arg = E.get();
1241 E = S.BuildCallExpr(nullptr, Get, Loc, Arg, Loc);
1242 }
1243 if (E.isInvalid())
1244 return true;
1245 Expr *Init = E.get();
1246
1247 // Given the type T designated by std::tuple_element<i - 1, E>::type,
1248 QualType T = getTupleLikeElementType(S, Loc, I, DecompType);
1249 if (T.isNull())
1250 return true;
1251
1252 // each vi is a variable of type "reference to T" initialized with the
1253 // initializer, where the reference is an lvalue reference if the
1254 // initializer is an lvalue and an rvalue reference otherwise
1255 QualType RefType =
1256 S.BuildReferenceType(T, E.get()->isLValue(), Loc, B->getDeclName());
1257 if (RefType.isNull())
1258 return true;
1259 auto *RefVD = VarDecl::Create(
1260 S.Context, Src->getDeclContext(), Loc, Loc,
1261 B->getDeclName().getAsIdentifierInfo(), RefType,
1262 S.Context.getTrivialTypeSourceInfo(T, Loc), Src->getStorageClass());
1263 RefVD->setLexicalDeclContext(Src->getLexicalDeclContext());
1264 RefVD->setTSCSpec(Src->getTSCSpec());
1265 RefVD->setImplicit();
1266 if (Src->isInlineSpecified())
1267 RefVD->setInlineSpecified();
1268 RefVD->getLexicalDeclContext()->addHiddenDecl(RefVD);
1269
1270 InitializedEntity Entity = InitializedEntity::InitializeBinding(RefVD);
1271 InitializationKind Kind = InitializationKind::CreateCopy(Loc, Loc);
1272 InitializationSequence Seq(S, Entity, Kind, Init);
1273 E = Seq.Perform(S, Entity, Kind, Init);
1274 if (E.isInvalid())
1275 return true;
1276 E = S.ActOnFinishFullExpr(E.get(), Loc, /*DiscardedValue*/ false);
1277 if (E.isInvalid())
1278 return true;
1279 RefVD->setInit(E.get());
1280 S.CheckCompleteVariableDeclaration(RefVD);
1281
1282 E = S.BuildDeclarationNameExpr(CXXScopeSpec(),
1283 DeclarationNameInfo(B->getDeclName(), Loc),
1284 RefVD);
1285 if (E.isInvalid())
1286 return true;
1287
1288 B->setBinding(T, E.get());
1289 I++;
1290 }
1291
1292 return false;
1293}
1294
1295/// Find the base class to decompose in a built-in decomposition of a class type.
1296/// This base class search is, unfortunately, not quite like any other that we
1297/// perform anywhere else in C++.
1298static DeclAccessPair findDecomposableBaseClass(Sema &S, SourceLocation Loc,
1299 const CXXRecordDecl *RD,
1300 CXXCastPath &BasePath) {
1301 auto BaseHasFields = [](const CXXBaseSpecifier *Specifier,
1302 CXXBasePath &Path) {
1303 return Specifier->getType()->getAsCXXRecordDecl()->hasDirectFields();
1304 };
1305
1306 const CXXRecordDecl *ClassWithFields = nullptr;
1307 AccessSpecifier AS = AS_public;
1308 if (RD->hasDirectFields())
1309 // [dcl.decomp]p4:
1310 // Otherwise, all of E's non-static data members shall be public direct
1311 // members of E ...
1312 ClassWithFields = RD;
1313 else {
1314 // ... or of ...
1315 CXXBasePaths Paths;
1316 Paths.setOrigin(const_cast<CXXRecordDecl*>(RD));
1317 if (!RD->lookupInBases(BaseHasFields, Paths)) {
1318 // If no classes have fields, just decompose RD itself. (This will work
1319 // if and only if zero bindings were provided.)
1320 return DeclAccessPair::make(const_cast<CXXRecordDecl*>(RD), AS_public);
1321 }
1322
1323 CXXBasePath *BestPath = nullptr;
1324 for (auto &P : Paths) {
1325 if (!BestPath)
1326 BestPath = &P;
1327 else if (!S.Context.hasSameType(P.back().Base->getType(),
1328 BestPath->back().Base->getType())) {
1329 // ... the same ...
1330 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1331 << false << RD << BestPath->back().Base->getType()
1332 << P.back().Base->getType();
1333 return DeclAccessPair();
1334 } else if (P.Access < BestPath->Access) {
1335 BestPath = &P;
1336 }
1337 }
1338
1339 // ... unambiguous ...
1340 QualType BaseType = BestPath->back().Base->getType();
1341 if (Paths.isAmbiguous(S.Context.getCanonicalType(BaseType))) {
1342 S.Diag(Loc, diag::err_decomp_decl_ambiguous_base)
1343 << RD << BaseType << S.getAmbiguousPathsDisplayString(Paths);
1344 return DeclAccessPair();
1345 }
1346
1347 // ... [accessible, implied by other rules] base class of E.
1348 S.CheckBaseClassAccess(Loc, BaseType, S.Context.getRecordType(RD),
1349 *BestPath, diag::err_decomp_decl_inaccessible_base);
1350 AS = BestPath->Access;
1351
1352 ClassWithFields = BaseType->getAsCXXRecordDecl();
1353 S.BuildBasePathArray(Paths, BasePath);
1354 }
1355
1356 // The above search did not check whether the selected class itself has base
1357 // classes with fields, so check that now.
1358 CXXBasePaths Paths;
1359 if (ClassWithFields->lookupInBases(BaseHasFields, Paths)) {
1360 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1361 << (ClassWithFields == RD) << RD << ClassWithFields
1362 << Paths.front().back().Base->getType();
1363 return DeclAccessPair();
1364 }
1365
1366 return DeclAccessPair::make(const_cast<CXXRecordDecl*>(ClassWithFields), AS);
1367}
1368
1369static bool checkMemberDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
1370 ValueDecl *Src, QualType DecompType,
1371 const CXXRecordDecl *OrigRD) {
1372 if (S.RequireCompleteType(Src->getLocation(), DecompType,
1373 diag::err_incomplete_type))
1374 return true;
1375
1376 CXXCastPath BasePath;
1377 DeclAccessPair BasePair =
1378 findDecomposableBaseClass(S, Src->getLocation(), OrigRD, BasePath);
1379 const CXXRecordDecl *RD = cast_or_null<CXXRecordDecl>(BasePair.getDecl());
1380 if (!RD)
1381 return true;
1382 QualType BaseType = S.Context.getQualifiedType(S.Context.getRecordType(RD),
1383 DecompType.getQualifiers());
1384
1385 auto DiagnoseBadNumberOfBindings = [&]() -> bool {
1386 unsigned NumFields =
1387 std::count_if(RD->field_begin(), RD->field_end(),
1388 [](FieldDecl *FD) { return !FD->isUnnamedBitfield(); });
1389 assert(Bindings.size() != NumFields)(static_cast<void> (0));
1390 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1391 << DecompType << (unsigned)Bindings.size() << NumFields << NumFields
1392 << (NumFields < Bindings.size());
1393 return true;
1394 };
1395
1396 // all of E's non-static data members shall be [...] well-formed
1397 // when named as e.name in the context of the structured binding,
1398 // E shall not have an anonymous union member, ...
1399 unsigned I = 0;
1400 for (auto *FD : RD->fields()) {
1401 if (FD->isUnnamedBitfield())
1402 continue;
1403
1404 // All the non-static data members are required to be nameable, so they
1405 // must all have names.
1406 if (!FD->getDeclName()) {
1407 if (RD->isLambda()) {
1408 S.Diag(Src->getLocation(), diag::err_decomp_decl_lambda);
1409 S.Diag(RD->getLocation(), diag::note_lambda_decl);
1410 return true;
1411 }
1412
1413 if (FD->isAnonymousStructOrUnion()) {
1414 S.Diag(Src->getLocation(), diag::err_decomp_decl_anon_union_member)
1415 << DecompType << FD->getType()->isUnionType();
1416 S.Diag(FD->getLocation(), diag::note_declared_at);
1417 return true;
1418 }
1419
1420 // FIXME: Are there any other ways we could have an anonymous member?
1421 }
1422
1423 // We have a real field to bind.
1424 if (I >= Bindings.size())
1425 return DiagnoseBadNumberOfBindings();
1426 auto *B = Bindings[I++];
1427 SourceLocation Loc = B->getLocation();
1428
1429 // The field must be accessible in the context of the structured binding.
1430 // We already checked that the base class is accessible.
1431 // FIXME: Add 'const' to AccessedEntity's classes so we can remove the
1432 // const_cast here.
1433 S.CheckStructuredBindingMemberAccess(
1434 Loc, const_cast<CXXRecordDecl *>(OrigRD),
1435 DeclAccessPair::make(FD, CXXRecordDecl::MergeAccess(
1436 BasePair.getAccess(), FD->getAccess())));
1437
1438 // Initialize the binding to Src.FD.
1439 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1440 if (E.isInvalid())
1441 return true;
1442 E = S.ImpCastExprToType(E.get(), BaseType, CK_UncheckedDerivedToBase,
1443 VK_LValue, &BasePath);
1444 if (E.isInvalid())
1445 return true;
1446 E = S.BuildFieldReferenceExpr(E.get(), /*IsArrow*/ false, Loc,
1447 CXXScopeSpec(), FD,
1448 DeclAccessPair::make(FD, FD->getAccess()),
1449 DeclarationNameInfo(FD->getDeclName(), Loc));
1450 if (E.isInvalid())
1451 return true;
1452
1453 // If the type of the member is T, the referenced type is cv T, where cv is
1454 // the cv-qualification of the decomposition expression.
1455 //
1456 // FIXME: We resolve a defect here: if the field is mutable, we do not add
1457 // 'const' to the type of the field.
1458 Qualifiers Q = DecompType.getQualifiers();
1459 if (FD->isMutable())
1460 Q.removeConst();
1461 B->setBinding(S.BuildQualifiedType(FD->getType(), Loc, Q), E.get());
1462 }
1463
1464 if (I != Bindings.size())
1465 return DiagnoseBadNumberOfBindings();
1466
1467 return false;
1468}
1469
1470void Sema::CheckCompleteDecompositionDeclaration(DecompositionDecl *DD) {
1471 QualType DecompType = DD->getType();
1472
1473 // If the type of the decomposition is dependent, then so is the type of
1474 // each binding.
1475 if (DecompType->isDependentType()) {
1476 for (auto *B : DD->bindings())
1477 B->setType(Context.DependentTy);
1478 return;
1479 }
1480
1481 DecompType = DecompType.getNonReferenceType();
1482 ArrayRef<BindingDecl*> Bindings = DD->bindings();
1483
1484 // C++1z [dcl.decomp]/2:
1485 // If E is an array type [...]
1486 // As an extension, we also support decomposition of built-in complex and
1487 // vector types.
1488 if (auto *CAT = Context.getAsConstantArrayType(DecompType)) {
1489 if (checkArrayDecomposition(*this, Bindings, DD, DecompType, CAT))
1490 DD->setInvalidDecl();
1491 return;
1492 }
1493 if (auto *VT = DecompType->getAs<VectorType>()) {
1494 if (checkVectorDecomposition(*this, Bindings, DD, DecompType, VT))
1495 DD->setInvalidDecl();
1496 return;
1497 }
1498 if (auto *CT = DecompType->getAs<ComplexType>()) {
1499 if (checkComplexDecomposition(*this, Bindings, DD, DecompType, CT))
1500 DD->setInvalidDecl();
1501 return;
1502 }
1503
1504 // C++1z [dcl.decomp]/3:
1505 // if the expression std::tuple_size<E>::value is a well-formed integral
1506 // constant expression, [...]
1507 llvm::APSInt TupleSize(32);
1508 switch (isTupleLike(*this, DD->getLocation(), DecompType, TupleSize)) {
1509 case IsTupleLike::Error:
1510 DD->setInvalidDecl();
1511 return;
1512
1513 case IsTupleLike::TupleLike:
1514 if (checkTupleLikeDecomposition(*this, Bindings, DD, DecompType, TupleSize))
1515 DD->setInvalidDecl();
1516 return;
1517
1518 case IsTupleLike::NotTupleLike:
1519 break;
1520 }
1521
1522 // C++1z [dcl.dcl]/8:
1523 // [E shall be of array or non-union class type]
1524 CXXRecordDecl *RD = DecompType->getAsCXXRecordDecl();
1525 if (!RD || RD->isUnion()) {
1526 Diag(DD->getLocation(), diag::err_decomp_decl_unbindable_type)
1527 << DD << !RD << DecompType;
1528 DD->setInvalidDecl();
1529 return;
1530 }
1531
1532 // C++1z [dcl.decomp]/4:
1533 // all of E's non-static data members shall be [...] direct members of
1534 // E or of the same unambiguous public base class of E, ...
1535 if (checkMemberDecomposition(*this, Bindings, DD, DecompType, RD))
1536 DD->setInvalidDecl();
1537}
1538
1539/// Merge the exception specifications of two variable declarations.
1540///
1541/// This is called when there's a redeclaration of a VarDecl. The function
1542/// checks if the redeclaration might have an exception specification and
1543/// validates compatibility and merges the specs if necessary.
1544void Sema::MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old) {
1545 // Shortcut if exceptions are disabled.
1546 if (!getLangOpts().CXXExceptions)
1547 return;
1548
1549 assert(Context.hasSameType(New->getType(), Old->getType()) &&(static_cast<void> (0))
1550 "Should only be called if types are otherwise the same.")(static_cast<void> (0));
1551
1552 QualType NewType = New->getType();
1553 QualType OldType = Old->getType();
1554
1555 // We're only interested in pointers and references to functions, as well
1556 // as pointers to member functions.
1557 if (const ReferenceType *R = NewType->getAs<ReferenceType>()) {
1558 NewType = R->getPointeeType();
1559 OldType = OldType->castAs<ReferenceType>()->getPointeeType();
1560 } else if (const PointerType *P = NewType->getAs<PointerType>()) {
1561 NewType = P->getPointeeType();
1562 OldType = OldType->castAs<PointerType>()->getPointeeType();
1563 } else if (const MemberPointerType *M = NewType->getAs<MemberPointerType>()) {
1564 NewType = M->getPointeeType();
1565 OldType = OldType->castAs<MemberPointerType>()->getPointeeType();
1566 }
1567
1568 if (!NewType->isFunctionProtoType())
1569 return;
1570
1571 // There's lots of special cases for functions. For function pointers, system
1572 // libraries are hopefully not as broken so that we don't need these
1573 // workarounds.
1574 if (CheckEquivalentExceptionSpec(
1575 OldType->getAs<FunctionProtoType>(), Old->getLocation(),
1576 NewType->getAs<FunctionProtoType>(), New->getLocation())) {
1577 New->setInvalidDecl();
1578 }
1579}
1580
1581/// CheckCXXDefaultArguments - Verify that the default arguments for a
1582/// function declaration are well-formed according to C++
1583/// [dcl.fct.default].
1584void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) {
1585 unsigned NumParams = FD->getNumParams();
1586 unsigned ParamIdx = 0;
1587
1588 // This checking doesn't make sense for explicit specializations; their
1589 // default arguments are determined by the declaration we're specializing,
1590 // not by FD.
1591 if (FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
1592 return;
1593 if (auto *FTD = FD->getDescribedFunctionTemplate())
1594 if (FTD->isMemberSpecialization())
1595 return;
1596
1597 // Find first parameter with a default argument
1598 for (; ParamIdx < NumParams; ++ParamIdx) {
1599 ParmVarDecl *Param = FD->getParamDecl(ParamIdx);
1600 if (Param->hasDefaultArg())
1601 break;
1602 }
1603
1604 // C++20 [dcl.fct.default]p4:
1605 // In a given function declaration, each parameter subsequent to a parameter
1606 // with a default argument shall have a default argument supplied in this or
1607 // a previous declaration, unless the parameter was expanded from a
1608 // parameter pack, or shall be a function parameter pack.
1609 for (; ParamIdx < NumParams; ++ParamIdx) {
1610 ParmVarDecl *Param = FD->getParamDecl(ParamIdx);
1611 if (!Param->hasDefaultArg() && !Param->isParameterPack() &&
1612 !(CurrentInstantiationScope &&
1613 CurrentInstantiationScope->isLocalPackExpansion(Param))) {
1614 if (Param->isInvalidDecl())
1615 /* We already complained about this parameter. */;
1616 else if (Param->getIdentifier())
1617 Diag(Param->getLocation(),
1618 diag::err_param_default_argument_missing_name)
1619 << Param->getIdentifier();
1620 else
1621 Diag(Param->getLocation(),
1622 diag::err_param_default_argument_missing);
1623 }
1624 }
1625}
1626
1627/// Check that the given type is a literal type. Issue a diagnostic if not,
1628/// if Kind is Diagnose.
1629/// \return \c true if a problem has been found (and optionally diagnosed).
1630template <typename... Ts>
1631static bool CheckLiteralType(Sema &SemaRef, Sema::CheckConstexprKind Kind,
1632 SourceLocation Loc, QualType T, unsigned DiagID,
1633 Ts &&...DiagArgs) {
1634 if (T->isDependentType())
1635 return false;
1636
1637 switch (Kind) {
1638 case Sema::CheckConstexprKind::Diagnose:
1639 return SemaRef.RequireLiteralType(Loc, T, DiagID,
1640 std::forward<Ts>(DiagArgs)...);
1641
1642 case Sema::CheckConstexprKind::CheckValid:
1643 return !T->isLiteralType(SemaRef.Context);
1644 }
1645
1646 llvm_unreachable("unknown CheckConstexprKind")__builtin_unreachable();
1647}
1648
1649/// Determine whether a destructor cannot be constexpr due to
1650static bool CheckConstexprDestructorSubobjects(Sema &SemaRef,
1651 const CXXDestructorDecl *DD,
1652 Sema::CheckConstexprKind Kind) {
1653 auto Check = [&](SourceLocation Loc, QualType T, const FieldDecl *FD) {
1654 const CXXRecordDecl *RD =
1655 T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
1656 if (!RD || RD->hasConstexprDestructor())
1657 return true;
1658
1659 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1660 SemaRef.Diag(DD->getLocation(), diag::err_constexpr_dtor_subobject)
1661 << static_cast<int>(DD->getConstexprKind()) << !FD
1662 << (FD ? FD->getDeclName() : DeclarationName()) << T;
1663 SemaRef.Diag(Loc, diag::note_constexpr_dtor_subobject)
1664 << !FD << (FD ? FD->getDeclName() : DeclarationName()) << T;
1665 }
1666 return false;
1667 };
1668
1669 const CXXRecordDecl *RD = DD->getParent();
1670 for (const CXXBaseSpecifier &B : RD->bases())
1671 if (!Check(B.getBaseTypeLoc(), B.getType(), nullptr))
1672 return false;
1673 for (const FieldDecl *FD : RD->fields())
1674 if (!Check(FD->getLocation(), FD->getType(), FD))
1675 return false;
1676 return true;
1677}
1678
1679/// Check whether a function's parameter types are all literal types. If so,
1680/// return true. If not, produce a suitable diagnostic and return false.
1681static bool CheckConstexprParameterTypes(Sema &SemaRef,
1682 const FunctionDecl *FD,
1683 Sema::CheckConstexprKind Kind) {
1684 unsigned ArgIndex = 0;
1685 const auto *FT = FD->getType()->castAs<FunctionProtoType>();
1686 for (FunctionProtoType::param_type_iterator i = FT->param_type_begin(),
1687 e = FT->param_type_end();
1688 i != e; ++i, ++ArgIndex) {
1689 const ParmVarDecl *PD = FD->getParamDecl(ArgIndex);
1690 SourceLocation ParamLoc = PD->getLocation();
1691 if (CheckLiteralType(SemaRef, Kind, ParamLoc, *i,
1692 diag::err_constexpr_non_literal_param, ArgIndex + 1,
1693 PD->getSourceRange(), isa<CXXConstructorDecl>(FD),
1694 FD->isConsteval()))
1695 return false;
1696 }
1697 return true;
1698}
1699
1700/// Check whether a function's return type is a literal type. If so, return
1701/// true. If not, produce a suitable diagnostic and return false.
1702static bool CheckConstexprReturnType(Sema &SemaRef, const FunctionDecl *FD,
1703 Sema::CheckConstexprKind Kind) {
1704 if (CheckLiteralType(SemaRef, Kind, FD->getLocation(), FD->getReturnType(),
1705 diag::err_constexpr_non_literal_return,
1706 FD->isConsteval()))
1707 return false;
1708 return true;
1709}
1710
1711/// Get diagnostic %select index for tag kind for
1712/// record diagnostic message.
1713/// WARNING: Indexes apply to particular diagnostics only!
1714///
1715/// \returns diagnostic %select index.
1716static unsigned getRecordDiagFromTagKind(TagTypeKind Tag) {
1717 switch (Tag) {
1718 case TTK_Struct: return 0;
1719 case TTK_Interface: return 1;
1720 case TTK_Class: return 2;
1721 default: llvm_unreachable("Invalid tag kind for record diagnostic!")__builtin_unreachable();
1722 }
1723}
1724
1725static bool CheckConstexprFunctionBody(Sema &SemaRef, const FunctionDecl *Dcl,
1726 Stmt *Body,
1727 Sema::CheckConstexprKind Kind);
1728
1729// Check whether a function declaration satisfies the requirements of a
1730// constexpr function definition or a constexpr constructor definition. If so,
1731// return true. If not, produce appropriate diagnostics (unless asked not to by
1732// Kind) and return false.
1733//
1734// This implements C++11 [dcl.constexpr]p3,4, as amended by DR1360.
1735bool Sema::CheckConstexprFunctionDefinition(const FunctionDecl *NewFD,
1736 CheckConstexprKind Kind) {
1737 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
1738 if (MD && MD->isInstance()) {
1739 // C++11 [dcl.constexpr]p4:
1740 // The definition of a constexpr constructor shall satisfy the following
1741 // constraints:
1742 // - the class shall not have any virtual base classes;
1743 //
1744 // FIXME: This only applies to constructors and destructors, not arbitrary
1745 // member functions.
1746 const CXXRecordDecl *RD = MD->getParent();
1747 if (RD->getNumVBases()) {
1748 if (Kind == CheckConstexprKind::CheckValid)
1749 return false;
1750
1751 Diag(NewFD->getLocation(), diag::err_constexpr_virtual_base)
1752 << isa<CXXConstructorDecl>(NewFD)
1753 << getRecordDiagFromTagKind(RD->getTagKind()) << RD->getNumVBases();
1754 for (const auto &I : RD->vbases())
1755 Diag(I.getBeginLoc(), diag::note_constexpr_virtual_base_here)
1756 << I.getSourceRange();
1757 return false;
1758 }
1759 }
1760
1761 if (!isa<CXXConstructorDecl>(NewFD)) {
1762 // C++11 [dcl.constexpr]p3:
1763 // The definition of a constexpr function shall satisfy the following
1764 // constraints:
1765 // - it shall not be virtual; (removed in C++20)
1766 const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD);
1767 if (Method && Method->isVirtual()) {
1768 if (getLangOpts().CPlusPlus20) {
1769 if (Kind == CheckConstexprKind::Diagnose)
1770 Diag(Method->getLocation(), diag::warn_cxx17_compat_constexpr_virtual);
1771 } else {
1772 if (Kind == CheckConstexprKind::CheckValid)
1773 return false;
1774
1775 Method = Method->getCanonicalDecl();
1776 Diag(Method->getLocation(), diag::err_constexpr_virtual);
1777
1778 // If it's not obvious why this function is virtual, find an overridden
1779 // function which uses the 'virtual' keyword.
1780 const CXXMethodDecl *WrittenVirtual = Method;
1781 while (!WrittenVirtual->isVirtualAsWritten())
1782 WrittenVirtual = *WrittenVirtual->begin_overridden_methods();
1783 if (WrittenVirtual != Method)
1784 Diag(WrittenVirtual->getLocation(),
1785 diag::note_overridden_virtual_function);
1786 return false;
1787 }
1788 }
1789
1790 // - its return type shall be a literal type;
1791 if (!CheckConstexprReturnType(*this, NewFD, Kind))
1792 return false;
1793 }
1794
1795 if (auto *Dtor = dyn_cast<CXXDestructorDecl>(NewFD)) {
1796 // A destructor can be constexpr only if the defaulted destructor could be;
1797 // we don't need to check the members and bases if we already know they all
1798 // have constexpr destructors.
1799 if (!Dtor->getParent()->defaultedDestructorIsConstexpr()) {
1800 if (Kind == CheckConstexprKind::CheckValid)
1801 return false;
1802 if (!CheckConstexprDestructorSubobjects(*this, Dtor, Kind))
1803 return false;
1804 }
1805 }
1806
1807 // - each of its parameter types shall be a literal type;
1808 if (!CheckConstexprParameterTypes(*this, NewFD, Kind))
1809 return false;
1810
1811 Stmt *Body = NewFD->getBody();
1812 assert(Body &&(static_cast<void> (0))
1813 "CheckConstexprFunctionDefinition called on function with no body")(static_cast<void> (0));
1814 return CheckConstexprFunctionBody(*this, NewFD, Body, Kind);
1815}
1816
1817/// Check the given declaration statement is legal within a constexpr function
1818/// body. C++11 [dcl.constexpr]p3,p4, and C++1y [dcl.constexpr]p3.
1819///
1820/// \return true if the body is OK (maybe only as an extension), false if we
1821/// have diagnosed a problem.
1822static bool CheckConstexprDeclStmt(Sema &SemaRef, const FunctionDecl *Dcl,
1823 DeclStmt *DS, SourceLocation &Cxx1yLoc,
1824 Sema::CheckConstexprKind Kind) {
1825 // C++11 [dcl.constexpr]p3 and p4:
1826 // The definition of a constexpr function(p3) or constructor(p4) [...] shall
1827 // contain only
1828 for (const auto *DclIt : DS->decls()) {
1829 switch (DclIt->getKind()) {
1830 case Decl::StaticAssert:
1831 case Decl::Using:
1832 case Decl::UsingShadow:
1833 case Decl::UsingDirective:
1834 case Decl::UnresolvedUsingTypename:
1835 case Decl::UnresolvedUsingValue:
1836 case Decl::UsingEnum:
1837 // - static_assert-declarations
1838 // - using-declarations,
1839 // - using-directives,
1840 // - using-enum-declaration
1841 continue;
1842
1843 case Decl::Typedef:
1844 case Decl::TypeAlias: {
1845 // - typedef declarations and alias-declarations that do not define
1846 // classes or enumerations,
1847 const auto *TN = cast<TypedefNameDecl>(DclIt);
1848 if (TN->getUnderlyingType()->isVariablyModifiedType()) {
1849 // Don't allow variably-modified types in constexpr functions.
1850 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1851 TypeLoc TL = TN->getTypeSourceInfo()->getTypeLoc();
1852 SemaRef.Diag(TL.getBeginLoc(), diag::err_constexpr_vla)
1853 << TL.getSourceRange() << TL.getType()
1854 << isa<CXXConstructorDecl>(Dcl);
1855 }
1856 return false;
1857 }
1858 continue;
1859 }
1860
1861 case Decl::Enum:
1862 case Decl::CXXRecord:
1863 // C++1y allows types to be defined, not just declared.
1864 if (cast<TagDecl>(DclIt)->isThisDeclarationADefinition()) {
1865 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1866 SemaRef.Diag(DS->getBeginLoc(),
1867 SemaRef.getLangOpts().CPlusPlus14
1868 ? diag::warn_cxx11_compat_constexpr_type_definition
1869 : diag::ext_constexpr_type_definition)
1870 << isa<CXXConstructorDecl>(Dcl);
1871 } else if (!SemaRef.getLangOpts().CPlusPlus14) {
1872 return false;
1873 }
1874 }
1875 continue;
1876
1877 case Decl::EnumConstant:
1878 case Decl::IndirectField:
1879 case Decl::ParmVar:
1880 // These can only appear with other declarations which are banned in
1881 // C++11 and permitted in C++1y, so ignore them.
1882 continue;
1883
1884 case Decl::Var:
1885 case Decl::Decomposition: {
1886 // C++1y [dcl.constexpr]p3 allows anything except:
1887 // a definition of a variable of non-literal type or of static or
1888 // thread storage duration or [before C++2a] for which no
1889 // initialization is performed.
1890 const auto *VD = cast<VarDecl>(DclIt);
1891 if (VD->isThisDeclarationADefinition()) {
1892 if (VD->isStaticLocal()) {
1893 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1894 SemaRef.Diag(VD->getLocation(),
1895 diag::err_constexpr_local_var_static)
1896 << isa<CXXConstructorDecl>(Dcl)
1897 << (VD->getTLSKind() == VarDecl::TLS_Dynamic);
1898 }
1899 return false;
1900 }
1901 if (CheckLiteralType(SemaRef, Kind, VD->getLocation(), VD->getType(),
1902 diag::err_constexpr_local_var_non_literal_type,
1903 isa<CXXConstructorDecl>(Dcl)))
1904 return false;
1905 if (!VD->getType()->isDependentType() &&
1906 !VD->hasInit() && !VD->isCXXForRangeDecl()) {
1907 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1908 SemaRef.Diag(
1909 VD->getLocation(),
1910 SemaRef.getLangOpts().CPlusPlus20
1911 ? diag::warn_cxx17_compat_constexpr_local_var_no_init
1912 : diag::ext_constexpr_local_var_no_init)
1913 << isa<CXXConstructorDecl>(Dcl);
1914 } else if (!SemaRef.getLangOpts().CPlusPlus20) {
1915 return false;
1916 }
1917 continue;
1918 }
1919 }
1920 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1921 SemaRef.Diag(VD->getLocation(),
1922 SemaRef.getLangOpts().CPlusPlus14
1923 ? diag::warn_cxx11_compat_constexpr_local_var
1924 : diag::ext_constexpr_local_var)
1925 << isa<CXXConstructorDecl>(Dcl);
1926 } else if (!SemaRef.getLangOpts().CPlusPlus14) {
1927 return false;
1928 }
1929 continue;
1930 }
1931
1932 case Decl::NamespaceAlias:
1933 case Decl::Function:
1934 // These are disallowed in C++11 and permitted in C++1y. Allow them
1935 // everywhere as an extension.
1936 if (!Cxx1yLoc.isValid())
1937 Cxx1yLoc = DS->getBeginLoc();
1938 continue;
1939
1940 default:
1941 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1942 SemaRef.Diag(DS->getBeginLoc(), diag::err_constexpr_body_invalid_stmt)
1943 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
1944 }
1945 return false;
1946 }
1947 }
1948
1949 return true;
1950}
1951
1952/// Check that the given field is initialized within a constexpr constructor.
1953///
1954/// \param Dcl The constexpr constructor being checked.
1955/// \param Field The field being checked. This may be a member of an anonymous
1956/// struct or union nested within the class being checked.
1957/// \param Inits All declarations, including anonymous struct/union members and
1958/// indirect members, for which any initialization was provided.
1959/// \param Diagnosed Whether we've emitted the error message yet. Used to attach
1960/// multiple notes for different members to the same error.
1961/// \param Kind Whether we're diagnosing a constructor as written or determining
1962/// whether the formal requirements are satisfied.
1963/// \return \c false if we're checking for validity and the constructor does
1964/// not satisfy the requirements on a constexpr constructor.
1965static bool CheckConstexprCtorInitializer(Sema &SemaRef,
1966 const FunctionDecl *Dcl,
1967 FieldDecl *Field,
1968 llvm::SmallSet<Decl*, 16> &Inits,
1969 bool &Diagnosed,
1970 Sema::CheckConstexprKind Kind) {
1971 // In C++20 onwards, there's nothing to check for validity.
1972 if (Kind == Sema::CheckConstexprKind::CheckValid &&
1973 SemaRef.getLangOpts().CPlusPlus20)
1974 return true;
1975
1976 if (Field->isInvalidDecl())
1977 return true;
1978
1979 if (Field->isUnnamedBitfield())
1980 return true;
1981
1982 // Anonymous unions with no variant members and empty anonymous structs do not
1983 // need to be explicitly initialized. FIXME: Anonymous structs that contain no
1984 // indirect fields don't need initializing.
1985 if (Field->isAnonymousStructOrUnion() &&
1986 (Field->getType()->isUnionType()
1987 ? !Field->getType()->getAsCXXRecordDecl()->hasVariantMembers()
1988 : Field->getType()->getAsCXXRecordDecl()->isEmpty()))
1989 return true;
1990
1991 if (!Inits.count(Field)) {
1992 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1993 if (!Diagnosed) {
1994 SemaRef.Diag(Dcl->getLocation(),
1995 SemaRef.getLangOpts().CPlusPlus20
1996 ? diag::warn_cxx17_compat_constexpr_ctor_missing_init
1997 : diag::ext_constexpr_ctor_missing_init);
1998 Diagnosed = true;
1999 }
2000 SemaRef.Diag(Field->getLocation(),
2001 diag::note_constexpr_ctor_missing_init);
2002 } else if (!SemaRef.getLangOpts().CPlusPlus20) {
2003 return false;
2004 }
2005 } else if (Field->isAnonymousStructOrUnion()) {
2006 const RecordDecl *RD = Field->getType()->castAs<RecordType>()->getDecl();
2007 for (auto *I : RD->fields())
2008 // If an anonymous union contains an anonymous struct of which any member
2009 // is initialized, all members must be initialized.
2010 if (!RD->isUnion() || Inits.count(I))
2011 if (!CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed,
2012 Kind))
2013 return false;
2014 }
2015 return true;
2016}
2017
2018/// Check the provided statement is allowed in a constexpr function
2019/// definition.
2020static bool
2021CheckConstexprFunctionStmt(Sema &SemaRef, const FunctionDecl *Dcl, Stmt *S,
2022 SmallVectorImpl<SourceLocation> &ReturnStmts,
2023 SourceLocation &Cxx1yLoc, SourceLocation &Cxx2aLoc,
2024 Sema::CheckConstexprKind Kind) {
2025 // - its function-body shall be [...] a compound-statement that contains only
2026 switch (S->getStmtClass()) {
2027 case Stmt::NullStmtClass:
2028 // - null statements,
2029 return true;
2030
2031 case Stmt::DeclStmtClass:
2032 // - static_assert-declarations
2033 // - using-declarations,
2034 // - using-directives,
2035 // - typedef declarations and alias-declarations that do not define
2036 // classes or enumerations,
2037 if (!CheckConstexprDeclStmt(SemaRef, Dcl, cast<DeclStmt>(S), Cxx1yLoc, Kind))
2038 return false;
2039 return true;
2040
2041 case Stmt::ReturnStmtClass:
2042 // - and exactly one return statement;
2043 if (isa<CXXConstructorDecl>(Dcl)) {
2044 // C++1y allows return statements in constexpr constructors.
2045 if (!Cxx1yLoc.isValid())
2046 Cxx1yLoc = S->getBeginLoc();
2047 return true;
2048 }
2049
2050 ReturnStmts.push_back(S->getBeginLoc());
2051 return true;
2052
2053 case Stmt::CompoundStmtClass: {
2054 // C++1y allows compound-statements.
2055 if (!Cxx1yLoc.isValid())
2056 Cxx1yLoc = S->getBeginLoc();
2057
2058 CompoundStmt *CompStmt = cast<CompoundStmt>(S);
2059 for (auto *BodyIt : CompStmt->body()) {
2060 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, BodyIt, ReturnStmts,
2061 Cxx1yLoc, Cxx2aLoc, Kind))
2062 return false;
2063 }
2064 return true;
2065 }
2066
2067 case Stmt::AttributedStmtClass:
2068 if (!Cxx1yLoc.isValid())
2069 Cxx1yLoc = S->getBeginLoc();
2070 return true;
2071
2072 case Stmt::IfStmtClass: {
2073 // C++1y allows if-statements.
2074 if (!Cxx1yLoc.isValid())
2075 Cxx1yLoc = S->getBeginLoc();
2076
2077 IfStmt *If = cast<IfStmt>(S);
2078 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, If->getThen(), ReturnStmts,
2079 Cxx1yLoc, Cxx2aLoc, Kind))
2080 return false;
2081 if (If->getElse() &&
2082 !CheckConstexprFunctionStmt(SemaRef, Dcl, If->getElse(), ReturnStmts,
2083 Cxx1yLoc, Cxx2aLoc, Kind))
2084 return false;
2085 return true;
2086 }
2087
2088 case Stmt::WhileStmtClass:
2089 case Stmt::DoStmtClass:
2090 case Stmt::ForStmtClass:
2091 case Stmt::CXXForRangeStmtClass:
2092 case Stmt::ContinueStmtClass:
2093 // C++1y allows all of these. We don't allow them as extensions in C++11,
2094 // because they don't make sense without variable mutation.
2095 if (!SemaRef.getLangOpts().CPlusPlus14)
2096 break;
2097 if (!Cxx1yLoc.isValid())
2098 Cxx1yLoc = S->getBeginLoc();
2099 for (Stmt *SubStmt : S->children())
2100 if (SubStmt &&
2101 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2102 Cxx1yLoc, Cxx2aLoc, Kind))
2103 return false;
2104 return true;
2105
2106 case Stmt::SwitchStmtClass:
2107 case Stmt::CaseStmtClass:
2108 case Stmt::DefaultStmtClass:
2109 case Stmt::BreakStmtClass:
2110 // C++1y allows switch-statements, and since they don't need variable
2111 // mutation, we can reasonably allow them in C++11 as an extension.
2112 if (!Cxx1yLoc.isValid())
2113 Cxx1yLoc = S->getBeginLoc();
2114 for (Stmt *SubStmt : S->children())
2115 if (SubStmt &&
2116 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2117 Cxx1yLoc, Cxx2aLoc, Kind))
2118 return false;
2119 return true;
2120
2121 case Stmt::GCCAsmStmtClass:
2122 case Stmt::MSAsmStmtClass:
2123 // C++2a allows inline assembly statements.
2124 case Stmt::CXXTryStmtClass:
2125 if (Cxx2aLoc.isInvalid())
2126 Cxx2aLoc = S->getBeginLoc();
2127 for (Stmt *SubStmt : S->children()) {
2128 if (SubStmt &&
2129 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2130 Cxx1yLoc, Cxx2aLoc, Kind))
2131 return false;
2132 }
2133 return true;
2134
2135 case Stmt::CXXCatchStmtClass:
2136 // Do not bother checking the language mode (already covered by the
2137 // try block check).
2138 if (!CheckConstexprFunctionStmt(SemaRef, Dcl,
2139 cast<CXXCatchStmt>(S)->getHandlerBlock(),
2140 ReturnStmts, Cxx1yLoc, Cxx2aLoc, Kind))
2141 return false;
2142 return true;
2143
2144 default:
2145 if (!isa<Expr>(S))
2146 break;
2147
2148 // C++1y allows expression-statements.
2149 if (!Cxx1yLoc.isValid())
2150 Cxx1yLoc = S->getBeginLoc();
2151 return true;
2152 }
2153
2154 if (Kind == Sema::CheckConstexprKind::Diagnose) {
2155 SemaRef.Diag(S->getBeginLoc(), diag::err_constexpr_body_invalid_stmt)
2156 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
2157 }
2158 return false;
2159}
2160
2161/// Check the body for the given constexpr function declaration only contains
2162/// the permitted types of statement. C++11 [dcl.constexpr]p3,p4.
2163///
2164/// \return true if the body is OK, false if we have found or diagnosed a
2165/// problem.
2166static bool CheckConstexprFunctionBody(Sema &SemaRef, const FunctionDecl *Dcl,
2167 Stmt *Body,
2168 Sema::CheckConstexprKind Kind) {
2169 SmallVector<SourceLocation, 4> ReturnStmts;
2170
2171 if (isa<CXXTryStmt>(Body)) {
2172 // C++11 [dcl.constexpr]p3:
2173 // The definition of a constexpr function shall satisfy the following
2174 // constraints: [...]
2175 // - its function-body shall be = delete, = default, or a
2176 // compound-statement
2177 //
2178 // C++11 [dcl.constexpr]p4:
2179 // In the definition of a constexpr constructor, [...]
2180 // - its function-body shall not be a function-try-block;
2181 //
2182 // This restriction is lifted in C++2a, as long as inner statements also
2183 // apply the general constexpr rules.
2184 switch (Kind) {
2185 case Sema::CheckConstexprKind::CheckValid:
2186 if (!SemaRef.getLangOpts().CPlusPlus20)
2187 return false;
2188 break;
2189
2190 case Sema::CheckConstexprKind::Diagnose:
2191 SemaRef.Diag(Body->getBeginLoc(),
2192 !SemaRef.getLangOpts().CPlusPlus20
2193 ? diag::ext_constexpr_function_try_block_cxx20
2194 : diag::warn_cxx17_compat_constexpr_function_try_block)
2195 << isa<CXXConstructorDecl>(Dcl);
2196 break;
2197 }
2198 }
2199
2200 // - its function-body shall be [...] a compound-statement that contains only
2201 // [... list of cases ...]
2202 //
2203 // Note that walking the children here is enough to properly check for
2204 // CompoundStmt and CXXTryStmt body.
2205 SourceLocation Cxx1yLoc, Cxx2aLoc;
2206 for (Stmt *SubStmt : Body->children()) {
2207 if (SubStmt &&
2208 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2209 Cxx1yLoc, Cxx2aLoc, Kind))
2210 return false;
2211 }
2212
2213 if (Kind == Sema::CheckConstexprKind::CheckValid) {
2214 // If this is only valid as an extension, report that we don't satisfy the
2215 // constraints of the current language.
2216 if ((Cxx2aLoc.isValid() && !SemaRef.getLangOpts().CPlusPlus20) ||
2217 (Cxx1yLoc.isValid() && !SemaRef.getLangOpts().CPlusPlus17))
2218 return false;
2219 } else if (Cxx2aLoc.isValid()) {
2220 SemaRef.Diag(Cxx2aLoc,
2221 SemaRef.getLangOpts().CPlusPlus20
2222 ? diag::warn_cxx17_compat_constexpr_body_invalid_stmt
2223 : diag::ext_constexpr_body_invalid_stmt_cxx20)
2224 << isa<CXXConstructorDecl>(Dcl);
2225 } else if (Cxx1yLoc.isValid()) {
2226 SemaRef.Diag(Cxx1yLoc,
2227 SemaRef.getLangOpts().CPlusPlus14
2228 ? diag::warn_cxx11_compat_constexpr_body_invalid_stmt
2229 : diag::ext_constexpr_body_invalid_stmt)
2230 << isa<CXXConstructorDecl>(Dcl);
2231 }
2232
2233 if (const CXXConstructorDecl *Constructor
2234 = dyn_cast<CXXConstructorDecl>(Dcl)) {
2235 const CXXRecordDecl *RD = Constructor->getParent();
2236 // DR1359:
2237 // - every non-variant non-static data member and base class sub-object
2238 // shall be initialized;
2239 // DR1460:
2240 // - if the class is a union having variant members, exactly one of them
2241 // shall be initialized;
2242 if (RD->isUnion()) {
2243 if (Constructor->getNumCtorInitializers() == 0 &&
2244 RD->hasVariantMembers()) {
2245 if (Kind == Sema::CheckConstexprKind::Diagnose) {
2246 SemaRef.Diag(
2247 Dcl->getLocation(),
2248 SemaRef.getLangOpts().CPlusPlus20
2249 ? diag::warn_cxx17_compat_constexpr_union_ctor_no_init
2250 : diag::ext_constexpr_union_ctor_no_init);
2251 } else if (!SemaRef.getLangOpts().CPlusPlus20) {
2252 return false;
2253 }
2254 }
2255 } else if (!Constructor->isDependentContext() &&
2256 !Constructor->isDelegatingConstructor()) {
2257 assert(RD->getNumVBases() == 0 && "constexpr ctor with virtual bases")(static_cast<void> (0));
2258
2259 // Skip detailed checking if we have enough initializers, and we would
2260 // allow at most one initializer per member.
2261 bool AnyAnonStructUnionMembers = false;
2262 unsigned Fields = 0;
2263 for (CXXRecordDecl::field_iterator I = RD->field_begin(),
2264 E = RD->field_end(); I != E; ++I, ++Fields) {
2265 if (I->isAnonymousStructOrUnion()) {
2266 AnyAnonStructUnionMembers = true;
2267 break;
2268 }
2269 }
2270 // DR1460:
2271 // - if the class is a union-like class, but is not a union, for each of
2272 // its anonymous union members having variant members, exactly one of
2273 // them shall be initialized;
2274 if (AnyAnonStructUnionMembers ||
2275 Constructor->getNumCtorInitializers() != RD->getNumBases() + Fields) {
2276 // Check initialization of non-static data members. Base classes are
2277 // always initialized so do not need to be checked. Dependent bases
2278 // might not have initializers in the member initializer list.
2279 llvm::SmallSet<Decl*, 16> Inits;
2280 for (const auto *I: Constructor->inits()) {
2281 if (FieldDecl *FD = I->getMember())
2282 Inits.insert(FD);
2283 else if (IndirectFieldDecl *ID = I->getIndirectMember())
2284 Inits.insert(ID->chain_begin(), ID->chain_end());
2285 }
2286
2287 bool Diagnosed = false;
2288 for (auto *I : RD->fields())
2289 if (!CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed,
2290 Kind))
2291 return false;
2292 }
2293 }
2294 } else {
2295 if (ReturnStmts.empty()) {
2296 // C++1y doesn't require constexpr functions to contain a 'return'
2297 // statement. We still do, unless the return type might be void, because
2298 // otherwise if there's no return statement, the function cannot
2299 // be used in a core constant expression.
2300 bool OK = SemaRef.getLangOpts().CPlusPlus14 &&
2301 (Dcl->getReturnType()->isVoidType() ||
2302 Dcl->getReturnType()->isDependentType());
2303 switch (Kind) {
2304 case Sema::CheckConstexprKind::Diagnose:
2305 SemaRef.Diag(Dcl->getLocation(),
2306 OK ? diag::warn_cxx11_compat_constexpr_body_no_return
2307 : diag::err_constexpr_body_no_return)
2308 << Dcl->isConsteval();
2309 if (!OK)
2310 return false;
2311 break;
2312
2313 case Sema::CheckConstexprKind::CheckValid:
2314 // The formal requirements don't include this rule in C++14, even
2315 // though the "must be able to produce a constant expression" rules
2316 // still imply it in some cases.
2317 if (!SemaRef.getLangOpts().CPlusPlus14)
2318 return false;
2319 break;
2320 }
2321 } else if (ReturnStmts.size() > 1) {
2322 switch (Kind) {
2323 case Sema::CheckConstexprKind::Diagnose:
2324 SemaRef.Diag(
2325 ReturnStmts.back(),
2326 SemaRef.getLangOpts().CPlusPlus14
2327 ? diag::warn_cxx11_compat_constexpr_body_multiple_return
2328 : diag::ext_constexpr_body_multiple_return);
2329 for (unsigned I = 0; I < ReturnStmts.size() - 1; ++I)
2330 SemaRef.Diag(ReturnStmts[I],
2331 diag::note_constexpr_body_previous_return);
2332 break;
2333
2334 case Sema::CheckConstexprKind::CheckValid:
2335 if (!SemaRef.getLangOpts().CPlusPlus14)
2336 return false;
2337 break;
2338 }
2339 }
2340 }
2341
2342 // C++11 [dcl.constexpr]p5:
2343 // if no function argument values exist such that the function invocation
2344 // substitution would produce a constant expression, the program is
2345 // ill-formed; no diagnostic required.
2346 // C++11 [dcl.constexpr]p3:
2347 // - every constructor call and implicit conversion used in initializing the
2348 // return value shall be one of those allowed in a constant expression.
2349 // C++11 [dcl.constexpr]p4:
2350 // - every constructor involved in initializing non-static data members and
2351 // base class sub-objects shall be a constexpr constructor.
2352 //
2353 // Note that this rule is distinct from the "requirements for a constexpr
2354 // function", so is not checked in CheckValid mode.
2355 SmallVector<PartialDiagnosticAt, 8> Diags;
2356 if (Kind == Sema::CheckConstexprKind::Diagnose &&
2357 !Expr::isPotentialConstantExpr(Dcl, Diags)) {
2358 SemaRef.Diag(Dcl->getLocation(),
2359 diag::ext_constexpr_function_never_constant_expr)
2360 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
2361 for (size_t I = 0, N = Diags.size(); I != N; ++I)
2362 SemaRef.Diag(Diags[I].first, Diags[I].second);
2363 // Don't return false here: we allow this for compatibility in
2364 // system headers.
2365 }
2366
2367 return true;
2368}
2369
2370/// Get the class that is directly named by the current context. This is the
2371/// class for which an unqualified-id in this scope could name a constructor
2372/// or destructor.
2373///
2374/// If the scope specifier denotes a class, this will be that class.
2375/// If the scope specifier is empty, this will be the class whose
2376/// member-specification we are currently within. Otherwise, there
2377/// is no such class.
2378CXXRecordDecl *Sema::getCurrentClass(Scope *, const CXXScopeSpec *SS) {
2379 assert(getLangOpts().CPlusPlus && "No class names in C!")(static_cast<void> (0));
2380
2381 if (SS && SS->isInvalid())
2382 return nullptr;
2383
2384 if (SS && SS->isNotEmpty()) {
2385 DeclContext *DC = computeDeclContext(*SS, true);
2386 return dyn_cast_or_null<CXXRecordDecl>(DC);
2387 }
2388
2389 return dyn_cast_or_null<CXXRecordDecl>(CurContext);
2390}
2391
2392/// isCurrentClassName - Determine whether the identifier II is the
2393/// name of the class type currently being defined. In the case of
2394/// nested classes, this will only return true if II is the name of
2395/// the innermost class.
2396bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *S,
2397 const CXXScopeSpec *SS) {
2398 CXXRecordDecl *CurDecl = getCurrentClass(S, SS);
2399 return CurDecl && &II == CurDecl->getIdentifier();
2400}
2401
2402/// Determine whether the identifier II is a typo for the name of
2403/// the class type currently being defined. If so, update it to the identifier
2404/// that should have been used.
2405bool Sema::isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS) {
2406 assert(getLangOpts().CPlusPlus && "No class names in C!")(static_cast<void> (0));
2407
2408 if (!getLangOpts().SpellChecking)
2409 return false;
2410
2411 CXXRecordDecl *CurDecl;
2412 if (SS && SS->isSet() && !SS->isInvalid()) {
2413 DeclContext *DC = computeDeclContext(*SS, true);
2414 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
2415 } else
2416 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
2417
2418 if (CurDecl && CurDecl->getIdentifier() && II != CurDecl->getIdentifier() &&
2419 3 * II->getName().edit_distance(CurDecl->getIdentifier()->getName())
2420 < II->getLength()) {
2421 II = CurDecl->getIdentifier();
2422 return true;
2423 }
2424
2425 return false;
2426}
2427
2428/// Determine whether the given class is a base class of the given
2429/// class, including looking at dependent bases.
2430static bool findCircularInheritance(const CXXRecordDecl *Class,
2431 const CXXRecordDecl *Current) {
2432 SmallVector<const CXXRecordDecl*, 8> Queue;
2433
2434 Class = Class->getCanonicalDecl();
2435 while (true) {
2436 for (const auto &I : Current->bases()) {
2437 CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
2438 if (!Base)
2439 continue;
2440
2441 Base = Base->getDefinition();
2442 if (!Base)
2443 continue;
2444
2445 if (Base->getCanonicalDecl() == Class)
2446 return true;
2447
2448 Queue.push_back(Base);
2449 }
2450
2451 if (Queue.empty())
2452 return false;
2453
2454 Current = Queue.pop_back_val();
2455 }
2456
2457 return false;
2458}
2459
2460/// Check the validity of a C++ base class specifier.
2461///
2462/// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics
2463/// and returns NULL otherwise.
2464CXXBaseSpecifier *
2465Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
2466 SourceRange SpecifierRange,
2467 bool Virtual, AccessSpecifier Access,
2468 TypeSourceInfo *TInfo,
2469 SourceLocation EllipsisLoc) {
2470 QualType BaseType = TInfo->getType();
2471 if (BaseType->containsErrors()) {
2472 // Already emitted a diagnostic when parsing the error type.
2473 return nullptr;
2474 }
2475 // C++ [class.union]p1:
2476 // A union shall not have base classes.
2477 if (Class->isUnion()) {
2478 Diag(Class->getLocation(), diag::err_base_clause_on_union)
2479 << SpecifierRange;
2480 return nullptr;
2481 }
2482
2483 if (EllipsisLoc.isValid() &&
2484 !TInfo->getType()->containsUnexpandedParameterPack()) {
2485 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
2486 << TInfo->getTypeLoc().getSourceRange();
2487 EllipsisLoc = SourceLocation();
2488 }
2489
2490 SourceLocation BaseLoc = TInfo->getTypeLoc().getBeginLoc();
2491
2492 if (BaseType->isDependentType()) {
2493 // Make sure that we don't have circular inheritance among our dependent
2494 // bases. For non-dependent bases, the check for completeness below handles
2495 // this.
2496 if (CXXRecordDecl *BaseDecl = BaseType->getAsCXXRecordDecl()) {
2497 if (BaseDecl->getCanonicalDecl() == Class->getCanonicalDecl() ||
2498 ((BaseDecl = BaseDecl->getDefinition()) &&
2499 findCircularInheritance(Class, BaseDecl))) {
2500 Diag(BaseLoc, diag::err_circular_inheritance)
2501 << BaseType << Context.getTypeDeclType(Class);
2502
2503 if (BaseDecl->getCanonicalDecl() != Class->getCanonicalDecl())
2504 Diag(BaseDecl->getLocation(), diag::note_previous_decl)
2505 << BaseType;
2506
2507 return nullptr;
2508 }
2509 }
2510
2511 // Make sure that we don't make an ill-formed AST where the type of the
2512 // Class is non-dependent and its attached base class specifier is an
2513 // dependent type, which violates invariants in many clang code paths (e.g.
2514 // constexpr evaluator). If this case happens (in errory-recovery mode), we
2515 // explicitly mark the Class decl invalid. The diagnostic was already
2516 // emitted.
2517 if (!Class->getTypeForDecl()->isDependentType())
2518 Class->setInvalidDecl();
2519 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2520 Class->getTagKind() == TTK_Class,
2521 Access, TInfo, EllipsisLoc);
2522 }
2523
2524 // Base specifiers must be record types.
2525 if (!BaseType->isRecordType()) {
2526 Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange;
2527 return nullptr;
2528 }
2529
2530 // C++ [class.union]p1:
2531 // A union shall not be used as a base class.
2532 if (BaseType->isUnionType()) {
2533 Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange;
2534 return nullptr;
2535 }
2536
2537 // For the MS ABI, propagate DLL attributes to base class templates.
2538 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2539 if (Attr *ClassAttr = getDLLAttr(Class)) {
2540 if (auto *BaseTemplate = dyn_cast_or_null<ClassTemplateSpecializationDecl>(
2541 BaseType->getAsCXXRecordDecl())) {
2542 propagateDLLAttrToBaseClassTemplate(Class, ClassAttr, BaseTemplate,
2543 BaseLoc);
2544 }
2545 }
2546 }
2547
2548 // C++ [class.derived]p2:
2549 // The class-name in a base-specifier shall not be an incompletely
2550 // defined class.
2551 if (RequireCompleteType(BaseLoc, BaseType,
2552 diag::err_incomplete_base_class, SpecifierRange)) {
2553 Class->setInvalidDecl();
2554 return nullptr;
2555 }
2556
2557 // If the base class is polymorphic or isn't empty, the new one is/isn't, too.
2558 RecordDecl *BaseDecl = BaseType->castAs<RecordType>()->getDecl();
2559 assert(BaseDecl && "Record type has no declaration")(static_cast<void> (0));
2560 BaseDecl = BaseDecl->getDefinition();
2561 assert(BaseDecl && "Base type is not incomplete, but has no definition")(static_cast<void> (0));
2562 CXXRecordDecl *CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
2563 assert(CXXBaseDecl && "Base type is not a C++ type")(static_cast<void> (0));
2564
2565 // Microsoft docs say:
2566 // "If a base-class has a code_seg attribute, derived classes must have the
2567 // same attribute."
2568 const auto *BaseCSA = CXXBaseDecl->getAttr<CodeSegAttr>();
2569 const auto *DerivedCSA = Class->getAttr<CodeSegAttr>();
2570 if ((DerivedCSA || BaseCSA) &&
2571 (!BaseCSA || !DerivedCSA || BaseCSA->getName() != DerivedCSA->getName())) {
2572 Diag(Class->getLocation(), diag::err_mismatched_code_seg_base);
2573 Diag(CXXBaseDecl->getLocation(), diag::note_base_class_specified_here)
2574 << CXXBaseDecl;
2575 return nullptr;
2576 }
2577
2578 // A class which contains a flexible array member is not suitable for use as a
2579 // base class:
2580 // - If the layout determines that a base comes before another base,
2581 // the flexible array member would index into the subsequent base.
2582 // - If the layout determines that base comes before the derived class,
2583 // the flexible array member would index into the derived class.
2584 if (CXXBaseDecl->hasFlexibleArrayMember()) {
2585 Diag(BaseLoc, diag::err_base_class_has_flexible_array_member)
2586 << CXXBaseDecl->getDeclName();
2587 return nullptr;
2588 }
2589
2590 // C++ [class]p3:
2591 // If a class is marked final and it appears as a base-type-specifier in
2592 // base-clause, the program is ill-formed.
2593 if (FinalAttr *FA = CXXBaseDecl->getAttr<FinalAttr>()) {
2594 Diag(BaseLoc, diag::err_class_marked_final_used_as_base)
2595 << CXXBaseDecl->getDeclName()
2596 << FA->isSpelledAsSealed();
2597 Diag(CXXBaseDecl->getLocation(), diag::note_entity_declared_at)
2598 << CXXBaseDecl->getDeclName() << FA->getRange();
2599 return nullptr;
2600 }
2601
2602 if (BaseDecl->isInvalidDecl())
2603 Class->setInvalidDecl();
2604
2605 // Create the base specifier.
2606 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2607 Class->getTagKind() == TTK_Class,
2608 Access, TInfo, EllipsisLoc);
2609}
2610
2611/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is
2612/// one entry in the base class list of a class specifier, for
2613/// example:
2614/// class foo : public bar, virtual private baz {
2615/// 'public bar' and 'virtual private baz' are each base-specifiers.
2616BaseResult
2617Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
2618 ParsedAttributes &Attributes,
2619 bool Virtual, AccessSpecifier Access,
2620 ParsedType basetype, SourceLocation BaseLoc,
2621 SourceLocation EllipsisLoc) {
2622 if (!classdecl)
2623 return true;
2624
2625 AdjustDeclIfTemplate(classdecl);
2626 CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(classdecl);
2627 if (!Class)
2628 return true;
2629
2630 // We haven't yet attached the base specifiers.
2631 Class->setIsParsingBaseSpecifiers();
2632
2633 // We do not support any C++11 attributes on base-specifiers yet.
2634 // Diagnose any attributes we see.
2635 for (const ParsedAttr &AL : Attributes) {
2636 if (AL.isInvalid() || AL.getKind() == ParsedAttr::IgnoredAttribute)
2637 continue;
2638 Diag(AL.getLoc(), AL.getKind() == ParsedAttr::UnknownAttribute
2639 ? (unsigned)diag::warn_unknown_attribute_ignored
2640 : (unsigned)diag::err_base_specifier_attribute)
2641 << AL << AL.getRange();
2642 }
2643
2644 TypeSourceInfo *TInfo = nullptr;
2645 GetTypeFromParser(basetype, &TInfo);
2646
2647 if (EllipsisLoc.isInvalid() &&
2648 DiagnoseUnexpandedParameterPack(SpecifierRange.getBegin(), TInfo,
2649 UPPC_BaseType))
2650 return true;
2651
2652 if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange,
2653 Virtual, Access, TInfo,
2654 EllipsisLoc))
2655 return BaseSpec;
2656 else
2657 Class->setInvalidDecl();
2658
2659 return true;
2660}
2661
2662/// Use small set to collect indirect bases. As this is only used
2663/// locally, there's no need to abstract the small size parameter.
2664typedef llvm::SmallPtrSet<QualType, 4> IndirectBaseSet;
2665
2666/// Recursively add the bases of Type. Don't add Type itself.
2667static void
2668NoteIndirectBases(ASTContext &Context, IndirectBaseSet &Set,
2669 const QualType &Type)
2670{
2671 // Even though the incoming type is a base, it might not be
2672 // a class -- it could be a template parm, for instance.
2673 if (auto Rec = Type->getAs<RecordType>()) {
2674 auto Decl = Rec->getAsCXXRecordDecl();
2675
2676 // Iterate over its bases.
2677 for (const auto &BaseSpec : Decl->bases()) {
2678 QualType Base = Context.getCanonicalType(BaseSpec.getType())
2679 .getUnqualifiedType();
2680 if (Set.insert(Base).second)
2681 // If we've not already seen it, recurse.
2682 NoteIndirectBases(Context, Set, Base);
2683 }
2684 }
2685}
2686
2687/// Performs the actual work of attaching the given base class
2688/// specifiers to a C++ class.
2689bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class,
2690 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2691 if (Bases.empty())
2692 return false;
2693
2694 // Used to keep track of which base types we have already seen, so
2695 // that we can properly diagnose redundant direct base types. Note
2696 // that the key is always the unqualified canonical type of the base
2697 // class.
2698 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes;
2699
2700 // Used to track indirect bases so we can see if a direct base is
2701 // ambiguous.
2702 IndirectBaseSet IndirectBaseTypes;
2703
2704 // Copy non-redundant base specifiers into permanent storage.
2705 unsigned NumGoodBases = 0;
2706 bool Invalid = false;
2707 for (unsigned idx = 0; idx < Bases.size(); ++idx) {
2708 QualType NewBaseType
2709 = Context.getCanonicalType(Bases[idx]->getType());
2710 NewBaseType = NewBaseType.getLocalUnqualifiedType();
2711
2712 CXXBaseSpecifier *&KnownBase = KnownBaseTypes[NewBaseType];
2713 if (KnownBase) {
2714 // C++ [class.mi]p3:
2715 // A class shall not be specified as a direct base class of a
2716 // derived class more than once.
2717 Diag(Bases[idx]->getBeginLoc(), diag::err_duplicate_base_class)
2718 << KnownBase->getType() << Bases[idx]->getSourceRange();
2719
2720 // Delete the duplicate base class specifier; we're going to
2721 // overwrite its pointer later.
2722 Context.Deallocate(Bases[idx]);
2723
2724 Invalid = true;
2725 } else {
2726 // Okay, add this new base class.
2727 KnownBase = Bases[idx];
2728 Bases[NumGoodBases++] = Bases[idx];
2729
2730 // Note this base's direct & indirect bases, if there could be ambiguity.
2731 if (Bases.size() > 1)
2732 NoteIndirectBases(Context, IndirectBaseTypes, NewBaseType);
2733
2734 if (const RecordType *Record = NewBaseType->getAs<RecordType>()) {
2735 const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
2736 if (Class->isInterface() &&
2737 (!RD->isInterfaceLike() ||
2738 KnownBase->getAccessSpecifier() != AS_public)) {
2739 // The Microsoft extension __interface does not permit bases that
2740 // are not themselves public interfaces.
2741 Diag(KnownBase->getBeginLoc(), diag::err_invalid_base_in_interface)
2742 << getRecordDiagFromTagKind(RD->getTagKind()) << RD
2743 << RD->getSourceRange();
2744 Invalid = true;
2745 }
2746 if (RD->hasAttr<WeakAttr>())
2747 Class->addAttr(WeakAttr::CreateImplicit(Context));
2748 }
2749 }
2750 }
2751
2752 // Attach the remaining base class specifiers to the derived class.
2753 Class->setBases(Bases.data(), NumGoodBases);
2754
2755 // Check that the only base classes that are duplicate are virtual.
2756 for (unsigned idx = 0; idx < NumGoodBases; ++idx) {
2757 // Check whether this direct base is inaccessible due to ambiguity.
2758 QualType BaseType = Bases[idx]->getType();
2759
2760 // Skip all dependent types in templates being used as base specifiers.
2761 // Checks below assume that the base specifier is a CXXRecord.
2762 if (BaseType->isDependentType())
2763 continue;
2764
2765 CanQualType CanonicalBase = Context.getCanonicalType(BaseType)
2766 .getUnqualifiedType();
2767
2768 if (IndirectBaseTypes.count(CanonicalBase)) {
2769 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2770 /*DetectVirtual=*/true);
2771 bool found
2772 = Class->isDerivedFrom(CanonicalBase->getAsCXXRecordDecl(), Paths);
2773 assert(found)(static_cast<void> (0));
2774 (void)found;
2775
2776 if (Paths.isAmbiguous(CanonicalBase))
2777 Diag(Bases[idx]->getBeginLoc(), diag::warn_inaccessible_base_class)
2778 << BaseType << getAmbiguousPathsDisplayString(Paths)
2779 << Bases[idx]->getSourceRange();
2780 else
2781 assert(Bases[idx]->isVirtual())(static_cast<void> (0));
2782 }
2783
2784 // Delete the base class specifier, since its data has been copied
2785 // into the CXXRecordDecl.
2786 Context.Deallocate(Bases[idx]);
2787 }
2788
2789 return Invalid;
2790}
2791
2792/// ActOnBaseSpecifiers - Attach the given base specifiers to the
2793/// class, after checking whether there are any duplicate base
2794/// classes.
2795void Sema::ActOnBaseSpecifiers(Decl *ClassDecl,
2796 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2797 if (!ClassDecl || Bases.empty())
2798 return;
2799
2800 AdjustDeclIfTemplate(ClassDecl);
2801 AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl), Bases);
2802}
2803
2804/// Determine whether the type \p Derived is a C++ class that is
2805/// derived from the type \p Base.
2806bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base) {
2807 if (!getLangOpts().CPlusPlus)
2808 return false;
2809
2810 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2811 if (!DerivedRD)
2812 return false;
2813
2814 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2815 if (!BaseRD)
2816 return false;
2817
2818 // If either the base or the derived type is invalid, don't try to
2819 // check whether one is derived from the other.
2820 if (BaseRD->isInvalidDecl() || DerivedRD->isInvalidDecl())
2821 return false;
2822
2823 // FIXME: In a modules build, do we need the entire path to be visible for us
2824 // to be able to use the inheritance relationship?
2825 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2826 return false;
2827
2828 return DerivedRD->isDerivedFrom(BaseRD);
2829}
2830
2831/// Determine whether the type \p Derived is a C++ class that is
2832/// derived from the type \p Base.
2833bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base,
2834 CXXBasePaths &Paths) {
2835 if (!getLangOpts().CPlusPlus)
2836 return false;
2837
2838 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2839 if (!DerivedRD)
2840 return false;
2841
2842 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2843 if (!BaseRD)
2844 return false;
2845
2846 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2847 return false;
2848
2849 return DerivedRD->isDerivedFrom(BaseRD, Paths);
2850}
2851
2852static void BuildBasePathArray(const CXXBasePath &Path,
2853 CXXCastPath &BasePathArray) {
2854 // We first go backward and check if we have a virtual base.
2855 // FIXME: It would be better if CXXBasePath had the base specifier for
2856 // the nearest virtual base.
2857 unsigned Start = 0;
2858 for (unsigned I = Path.size(); I != 0; --I) {
2859 if (Path[I - 1].Base->isVirtual()) {
2860 Start = I - 1;
2861 break;
2862 }
2863 }
2864
2865 // Now add all bases.
2866 for (unsigned I = Start, E = Path.size(); I != E; ++I)
2867 BasePathArray.push_back(const_cast<CXXBaseSpecifier*>(Path[I].Base));
2868}
2869
2870
2871void Sema::BuildBasePathArray(const CXXBasePaths &Paths,
2872 CXXCastPath &BasePathArray) {
2873 assert(BasePathArray.empty() && "Base path array must be empty!")(static_cast<void> (0));
2874 assert(Paths.isRecordingPaths() && "Must record paths!")(static_cast<void> (0));
2875 return ::BuildBasePathArray(Paths.front(), BasePathArray);
2876}
2877/// CheckDerivedToBaseConversion - Check whether the Derived-to-Base
2878/// conversion (where Derived and Base are class types) is
2879/// well-formed, meaning that the conversion is unambiguous (and
2880/// that all of the base classes are accessible). Returns true
2881/// and emits a diagnostic if the code is ill-formed, returns false
2882/// otherwise. Loc is the location where this routine should point to
2883/// if there is an error, and Range is the source range to highlight
2884/// if there is an error.
2885///
2886/// If either InaccessibleBaseID or AmbiguousBaseConvID are 0, then the
2887/// diagnostic for the respective type of error will be suppressed, but the
2888/// check for ill-formed code will still be performed.
2889bool
2890Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2891 unsigned InaccessibleBaseID,
2892 unsigned AmbiguousBaseConvID,
2893 SourceLocation Loc, SourceRange Range,
2894 DeclarationName Name,
2895 CXXCastPath *BasePath,
2896 bool IgnoreAccess) {
2897 // First, determine whether the path from Derived to Base is
2898 // ambiguous. This is slightly more expensive than checking whether
2899 // the Derived to Base conversion exists, because here we need to
2900 // explore multiple paths to determine if there is an ambiguity.
2901 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2902 /*DetectVirtual=*/false);
2903 bool DerivationOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2904 if (!DerivationOkay)
2905 return true;
2906
2907 const CXXBasePath *Path = nullptr;
2908 if (!Paths.isAmbiguous(Context.getCanonicalType(Base).getUnqualifiedType()))
2909 Path = &Paths.front();
2910
2911 // For MSVC compatibility, check if Derived directly inherits from Base. Clang
2912 // warns about this hierarchy under -Winaccessible-base, but MSVC allows the
2913 // user to access such bases.
2914 if (!Path && getLangOpts().MSVCCompat) {
2915 for (const CXXBasePath &PossiblePath : Paths) {
2916 if (PossiblePath.size() == 1) {
2917 Path = &PossiblePath;
2918 if (AmbiguousBaseConvID)
2919 Diag(Loc, diag::ext_ms_ambiguous_direct_base)
2920 << Base << Derived << Range;
2921 break;
2922 }
2923 }
2924 }
2925
2926 if (Path) {
2927 if (!IgnoreAccess) {
2928 // Check that the base class can be accessed.
2929 switch (
2930 CheckBaseClassAccess(Loc, Base, Derived, *Path, InaccessibleBaseID)) {
2931 case AR_inaccessible:
2932 return true;
2933 case AR_accessible:
2934 case AR_dependent:
2935 case AR_delayed:
2936 break;
2937 }
2938 }
2939
2940 // Build a base path if necessary.
2941 if (BasePath)
2942 ::BuildBasePathArray(*Path, *BasePath);
2943 return false;
2944 }
2945
2946 if (AmbiguousBaseConvID) {
2947 // We know that the derived-to-base conversion is ambiguous, and
2948 // we're going to produce a diagnostic. Perform the derived-to-base
2949 // search just one more time to compute all of the possible paths so
2950 // that we can print them out. This is more expensive than any of
2951 // the previous derived-to-base checks we've done, but at this point
2952 // performance isn't as much of an issue.
2953 Paths.clear();
2954 Paths.setRecordingPaths(true);
2955 bool StillOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2956 assert(StillOkay && "Can only be used with a derived-to-base conversion")(static_cast<void> (0));
2957 (void)StillOkay;
2958
2959 // Build up a textual representation of the ambiguous paths, e.g.,
2960 // D -> B -> A, that will be used to illustrate the ambiguous
2961 // conversions in the diagnostic. We only print one of the paths
2962 // to each base class subobject.
2963 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
2964
2965 Diag(Loc, AmbiguousBaseConvID)
2966 << Derived << Base << PathDisplayStr << Range << Name;
2967 }
2968 return true;
2969}
2970
2971bool
2972Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2973 SourceLocation Loc, SourceRange Range,
2974 CXXCastPath *BasePath,
2975 bool IgnoreAccess) {
2976 return CheckDerivedToBaseConversion(
2977 Derived, Base, diag::err_upcast_to_inaccessible_base,
2978 diag::err_ambiguous_derived_to_base_conv, Loc, Range, DeclarationName(),
2979 BasePath, IgnoreAccess);
2980}
2981
2982
2983/// Builds a string representing ambiguous paths from a
2984/// specific derived class to different subobjects of the same base
2985/// class.
2986///
2987/// This function builds a string that can be used in error messages
2988/// to show the different paths that one can take through the
2989/// inheritance hierarchy to go from the derived class to different
2990/// subobjects of a base class. The result looks something like this:
2991/// @code
2992/// struct D -> struct B -> struct A
2993/// struct D -> struct C -> struct A
2994/// @endcode
2995std::string Sema::getAmbiguousPathsDisplayString(CXXBasePaths &Paths) {
2996 std::string PathDisplayStr;
2997 std::set<unsigned> DisplayedPaths;
2998 for (CXXBasePaths::paths_iterator Path = Paths.begin();
2999 Path != Paths.end(); ++Path) {
3000 if (DisplayedPaths.insert(Path->back().SubobjectNumber).second) {
3001 // We haven't displayed a path to this particular base
3002 // class subobject yet.
3003 PathDisplayStr += "\n ";
3004 PathDisplayStr += Context.getTypeDeclType(Paths.getOrigin()).getAsString();
3005 for (CXXBasePath::const_iterator Element = Path->begin();
3006 Element != Path->end(); ++Element)
3007 PathDisplayStr += " -> " + Element->Base->getType().getAsString();
3008 }
3009 }
3010
3011 return PathDisplayStr;
3012}
3013
3014//===----------------------------------------------------------------------===//
3015// C++ class member Handling
3016//===----------------------------------------------------------------------===//
3017
3018/// ActOnAccessSpecifier - Parsed an access specifier followed by a colon.
3019bool Sema::ActOnAccessSpecifier(AccessSpecifier Access, SourceLocation ASLoc,
3020 SourceLocation ColonLoc,
3021 const ParsedAttributesView &Attrs) {
3022 assert(Access != AS_none && "Invalid kind for syntactic access specifier!")(static_cast<void> (0));
3023 AccessSpecDecl *ASDecl = AccessSpecDecl::Create(Context, Access, CurContext,
3024 ASLoc, ColonLoc);
3025 CurContext->addHiddenDecl(ASDecl);
3026 return ProcessAccessDeclAttributeList(ASDecl, Attrs);
3027}
3028
3029/// CheckOverrideControl - Check C++11 override control semantics.
3030void Sema::CheckOverrideControl(NamedDecl *D) {
3031 if (D->isInvalidDecl())
3032 return;
3033
3034 // We only care about "override" and "final" declarations.
3035 if (!D->hasAttr<OverrideAttr>() && !D->hasAttr<FinalAttr>())
3036 return;
3037
3038 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
3039
3040 // We can't check dependent instance methods.
3041 if (MD && MD->isInstance() &&
3042 (MD->getParent()->hasAnyDependentBases() ||
3043 MD->getType()->isDependentType()))
3044 return;
3045
3046 if (MD && !MD->isVirtual()) {
3047 // If we have a non-virtual method, check if if hides a virtual method.
3048 // (In that case, it's most likely the method has the wrong type.)
3049 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
3050 FindHiddenVirtualMethods(MD, OverloadedMethods);
3051
3052 if (!OverloadedMethods.empty()) {
3053 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
3054 Diag(OA->getLocation(),
3055 diag::override_keyword_hides_virtual_member_function)
3056 << "override" << (OverloadedMethods.size() > 1);
3057 } else if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
3058 Diag(FA->getLocation(),
3059 diag::override_keyword_hides_virtual_member_function)
3060 << (FA->isSpelledAsSealed() ? "sealed" : "final")
3061 << (OverloadedMethods.size() > 1);
3062 }
3063 NoteHiddenVirtualMethods(MD, OverloadedMethods);
3064 MD->setInvalidDecl();
3065 return;
3066 }
3067 // Fall through into the general case diagnostic.
3068 // FIXME: We might want to attempt typo correction here.
3069 }
3070
3071 if (!MD || !MD->isVirtual()) {
3072 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
3073 Diag(OA->getLocation(),
3074 diag::override_keyword_only_allowed_on_virtual_member_functions)
3075 << "override" << FixItHint::CreateRemoval(OA->getLocation());
3076 D->dropAttr<OverrideAttr>();
3077 }
3078 if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
3079 Diag(FA->getLocation(),
3080 diag::override_keyword_only_allowed_on_virtual_member_functions)
3081 << (FA->isSpelledAsSealed() ? "sealed" : "final")
3082 << FixItHint::CreateRemoval(FA->getLocation());
3083 D->dropAttr<FinalAttr>();
3084 }
3085 return;
3086 }
3087
3088 // C++11 [class.virtual]p5:
3089 // If a function is marked with the virt-specifier override and
3090 // does not override a member function of a base class, the program is
3091 // ill-formed.
3092 bool HasOverriddenMethods = MD->size_overridden_methods() != 0;
3093 if (MD->hasAttr<OverrideAttr>() && !HasOverriddenMethods)
3094 Diag(MD->getLocation(), diag::err_function_marked_override_not_overriding)
3095 << MD->getDeclName();
3096}
3097
3098void Sema::DiagnoseAbsenceOfOverrideControl(NamedDecl *D, bool Inconsistent) {
3099 if (D->isInvalidDecl() || D->hasAttr<OverrideAttr>())
3100 return;
3101 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
3102 if (!MD || MD->isImplicit() || MD->hasAttr<FinalAttr>())
3103 return;
3104
3105 SourceLocation Loc = MD->getLocation();
3106 SourceLocation SpellingLoc = Loc;
3107 if (getSourceManager().isMacroArgExpansion(Loc))
3108 SpellingLoc = getSourceManager().getImmediateExpansionRange(Loc).getBegin();
3109 SpellingLoc = getSourceManager().getSpellingLoc(SpellingLoc);
3110 if (SpellingLoc.isValid() && getSourceManager().isInSystemHeader(SpellingLoc))
3111 return;
3112
3113 if (MD->size_overridden_methods() > 0) {
3114 auto EmitDiag = [&](unsigned DiagInconsistent, unsigned DiagSuggest) {
3115 unsigned DiagID =
3116 Inconsistent && !Diags.isIgnored(DiagInconsistent, MD->getLocation())
3117 ? DiagInconsistent
3118 : DiagSuggest;
3119 Diag(MD->getLocation(), DiagID) << MD->getDeclName();
3120 const CXXMethodDecl *OMD = *MD->begin_overridden_methods();
3121 Diag(OMD->getLocation(), diag::note_overridden_virtual_function);
3122 };
3123 if (isa<CXXDestructorDecl>(MD))
3124 EmitDiag(
3125 diag::warn_inconsistent_destructor_marked_not_override_overriding,
3126 diag::warn_suggest_destructor_marked_not_override_overriding);
3127 else
3128 EmitDiag(diag::warn_inconsistent_function_marked_not_override_overriding,
3129 diag::warn_suggest_function_marked_not_override_overriding);
3130 }
3131}
3132
3133/// CheckIfOverriddenFunctionIsMarkedFinal - Checks whether a virtual member
3134/// function overrides a virtual member function marked 'final', according to
3135/// C++11 [class.virtual]p4.
3136bool Sema::CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
3137 const CXXMethodDecl *Old) {
3138 FinalAttr *FA = Old->getAttr<FinalAttr>();
3139 if (!FA)
3140 return false;
3141
3142 Diag(New->getLocation(), diag::err_final_function_overridden)
3143 << New->getDeclName()
3144 << FA->isSpelledAsSealed();
3145 Diag(Old->getLocation(), diag::note_overridden_virtual_function);
3146 return true;
3147}
3148
3149static bool InitializationHasSideEffects(const FieldDecl &FD) {
3150 const Type *T = FD.getType()->getBaseElementTypeUnsafe();
3151 // FIXME: Destruction of ObjC lifetime types has side-effects.
3152 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3153 return !RD->isCompleteDefinition() ||
3154 !RD->hasTrivialDefaultConstructor() ||
3155 !RD->hasTrivialDestructor();
3156 return false;
3157}
3158
3159static const ParsedAttr *getMSPropertyAttr(const ParsedAttributesView &list) {
3160 ParsedAttributesView::const_iterator Itr =
3161 llvm::find_if(list, [](const ParsedAttr &AL) {
3162 return AL.isDeclspecPropertyAttribute();
3163 });
3164 if (Itr != list.end())
3165 return &*Itr;
3166 return nullptr;
3167}
3168
3169// Check if there is a field shadowing.
3170void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,
3171 DeclarationName FieldName,
3172 const CXXRecordDecl *RD,
3173 bool DeclIsField) {
3174 if (Diags.isIgnored(diag::warn_shadow_field, Loc))
3175 return;
3176
3177 // To record a shadowed field in a base
3178 std::map<CXXRecordDecl*, NamedDecl*> Bases;
3179 auto FieldShadowed = [&](const CXXBaseSpecifier *Specifier,
3180 CXXBasePath &Path) {
3181 const auto Base = Specifier->getType()->getAsCXXRecordDecl();
3182 // Record an ambiguous path directly
3183 if (Bases.find(Base) != Bases.end())
3184 return true;
3185 for (const auto Field : Base->lookup(FieldName)) {
3186 if ((isa<FieldDecl>(Field) || isa<IndirectFieldDecl>(Field)) &&
3187 Field->getAccess() != AS_private) {
3188 assert(Field->getAccess() != AS_none)(static_cast<void> (0));
3189 assert(Bases.find(Base) == Bases.end())(static_cast<void> (0));
3190 Bases[Base] = Field;
3191 return true;
3192 }
3193 }
3194 return false;
3195 };
3196
3197 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
3198 /*DetectVirtual=*/true);
3199 if (!RD->lookupInBases(FieldShadowed, Paths))
3200 return;
3201
3202 for (const auto &P : Paths) {
3203 auto Base = P.back().Base->getType()->getAsCXXRecordDecl();
3204 auto It = Bases.find(Base);
3205 // Skip duplicated bases
3206 if (It == Bases.end())
3207 continue;
3208 auto BaseField = It->second;
3209 assert(BaseField->getAccess() != AS_private)(static_cast<void> (0));
3210 if (AS_none !=
3211 CXXRecordDecl::MergeAccess(P.Access, BaseField->getAccess())) {
3212 Diag(Loc, diag::warn_shadow_field)
3213 << FieldName << RD << Base << DeclIsField;
3214 Diag(BaseField->getLocation(), diag::note_shadow_field);
3215 Bases.erase(It);
3216 }
3217 }
3218}
3219
3220/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member
3221/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the
3222/// bitfield width if there is one, 'InitExpr' specifies the initializer if
3223/// one has been parsed, and 'InitStyle' is set if an in-class initializer is
3224/// present (but parsing it has been deferred).
3225NamedDecl *
3226Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D,
3227 MultiTemplateParamsArg TemplateParameterLists,
3228 Expr *BW, const VirtSpecifiers &VS,
3229 InClassInitStyle InitStyle) {
3230 const DeclSpec &DS = D.getDeclSpec();
3231 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
3232 DeclarationName Name = NameInfo.getName();
3233 SourceLocation Loc = NameInfo.getLoc();
3234
3235 // For anonymous bitfields, the location should point to the type.
3236 if (Loc.isInvalid())
3237 Loc = D.getBeginLoc();
3238
3239 Expr *BitWidth = static_cast<Expr*>(BW);
3240
3241 assert(isa<CXXRecordDecl>(CurContext))(static_cast<void> (0));
3242 assert(!DS.isFriendSpecified())(static_cast<void> (0));
3243
3244 bool isFunc = D.isDeclarationOfFunction();
3245 const ParsedAttr *MSPropertyAttr =
3246 getMSPropertyAttr(D.getDeclSpec().getAttributes());
3247
3248 if (cast<CXXRecordDecl>(CurContext)->isInterface()) {
3249 // The Microsoft extension __interface only permits public member functions
3250 // and prohibits constructors, destructors, operators, non-public member
3251 // functions, static methods and data members.
3252 unsigned InvalidDecl;
3253 bool ShowDeclName = true;
3254 if (!isFunc &&
3255 (DS.getStorageClassSpec() == DeclSpec::SCS_typedef || MSPropertyAttr))
3256 InvalidDecl = 0;
3257 else if (!isFunc)
3258 InvalidDecl = 1;
3259 else if (AS != AS_public)
3260 InvalidDecl = 2;
3261 else if (DS.getStorageClassSpec() == DeclSpec::SCS_static)
3262 InvalidDecl = 3;
3263 else switch (Name.getNameKind()) {
3264 case DeclarationName::CXXConstructorName:
3265 InvalidDecl = 4;
3266 ShowDeclName = false;
3267 break;
3268
3269 case DeclarationName::CXXDestructorName:
3270 InvalidDecl = 5;
3271 ShowDeclName = false;
3272 break;
3273
3274 case DeclarationName::CXXOperatorName:
3275 case DeclarationName::CXXConversionFunctionName:
3276 InvalidDecl = 6;
3277 break;
3278
3279 default:
3280 InvalidDecl = 0;
3281 break;
3282 }
3283
3284 if (InvalidDecl) {
3285 if (ShowDeclName)
3286 Diag(Loc, diag::err_invalid_member_in_interface)
3287 << (InvalidDecl-1) << Name;
3288 else
3289 Diag(Loc, diag::err_invalid_member_in_interface)
3290 << (InvalidDecl-1) << "";
3291 return nullptr;
3292 }
3293 }
3294
3295 // C++ 9.2p6: A member shall not be declared to have automatic storage
3296 // duration (auto, register) or with the extern storage-class-specifier.
3297 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class
3298 // data members and cannot be applied to names declared const or static,
3299 // and cannot be applied to reference members.
3300 switch (DS.getStorageClassSpec()) {
3301 case DeclSpec::SCS_unspecified:
3302 case DeclSpec::SCS_typedef:
3303 case DeclSpec::SCS_static:
3304 break;
3305 case DeclSpec::SCS_mutable:
3306 if (isFunc) {
3307 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function);
3308
3309 // FIXME: It would be nicer if the keyword was ignored only for this
3310 // declarator. Otherwise we could get follow-up errors.
3311 D.getMutableDeclSpec().ClearStorageClassSpecs();
3312 }
3313 break;
3314 default:
3315 Diag(DS.getStorageClassSpecLoc(),
3316 diag::err_storageclass_invalid_for_member);
3317 D.getMutableDeclSpec().ClearStorageClassSpecs();
3318 break;
3319 }
3320
3321 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified ||
3322 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) &&
3323 !isFunc);
3324
3325 if (DS.hasConstexprSpecifier() && isInstField) {
3326 SemaDiagnosticBuilder B =
3327 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr_member);
3328 SourceLocation ConstexprLoc = DS.getConstexprSpecLoc();
3329 if (InitStyle == ICIS_NoInit) {
3330 B << 0 << 0;
3331 if (D.getDeclSpec().getTypeQualifiers() & DeclSpec::TQ_const)
3332 B << FixItHint::CreateRemoval(ConstexprLoc);
3333 else {
3334 B << FixItHint::CreateReplacement(ConstexprLoc, "const");
3335 D.getMutableDeclSpec().ClearConstexprSpec();
3336 const char *PrevSpec;
3337 unsigned DiagID;
3338 bool Failed = D.getMutableDeclSpec().SetTypeQual(
3339 DeclSpec::TQ_const, ConstexprLoc, PrevSpec, DiagID, getLangOpts());
3340 (void)Failed;
3341 assert(!Failed && "Making a constexpr member const shouldn't fail")(static_cast<void> (0));
3342 }
3343 } else {
3344 B << 1;
3345 const char *PrevSpec;
3346 unsigned DiagID;
3347 if (D.getMutableDeclSpec().SetStorageClassSpec(
3348 *this, DeclSpec::SCS_static, ConstexprLoc, PrevSpec, DiagID,
3349 Context.getPrintingPolicy())) {
3350 assert(DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&(static_cast<void> (0))
3351 "This is the only DeclSpec that should fail to be applied")(static_cast<void> (0));
3352 B << 1;
3353 } else {
3354 B << 0 << FixItHint::CreateInsertion(ConstexprLoc, "static ");
3355 isInstField = false;
3356 }
3357 }
3358 }
3359
3360 NamedDecl *Member;
3361 if (isInstField) {
3362 CXXScopeSpec &SS = D.getCXXScopeSpec();
3363
3364 // Data members must have identifiers for names.
3365 if (!Name.isIdentifier()) {
3366 Diag(Loc, diag::err_bad_variable_name)
3367 << Name;
3368 return nullptr;
3369 }
3370
3371 IdentifierInfo *II = Name.getAsIdentifierInfo();
3372
3373 // Member field could not be with "template" keyword.
3374 // So TemplateParameterLists should be empty in this case.
3375 if (TemplateParameterLists.size()) {
3376 TemplateParameterList* TemplateParams = TemplateParameterLists[0];
3377 if (TemplateParams->size()) {
3378 // There is no such thing as a member field template.
3379 Diag(D.getIdentifierLoc(), diag::err_template_member)
3380 << II
3381 << SourceRange(TemplateParams->getTemplateLoc(),
3382 TemplateParams->getRAngleLoc());
3383 } else {
3384 // There is an extraneous 'template<>' for this member.
3385 Diag(TemplateParams->getTemplateLoc(),
3386 diag::err_template_member_noparams)
3387 << II
3388 << SourceRange(TemplateParams->getTemplateLoc(),
3389 TemplateParams->getRAngleLoc());
3390 }
3391 return nullptr;
3392 }
3393
3394 if (SS.isSet() && !SS.isInvalid()) {
3395 // The user provided a superfluous scope specifier inside a class
3396 // definition:
3397 //
3398 // class X {
3399 // int X::member;
3400 // };
3401 if (DeclContext *DC = computeDeclContext(SS, false))
3402 diagnoseQualifiedDeclaration(SS, DC, Name, D.getIdentifierLoc(),
3403 D.getName().getKind() ==
3404 UnqualifiedIdKind::IK_TemplateId);
3405 else
3406 Diag(D.getIdentifierLoc(), diag::err_member_qualification)
3407 << Name << SS.getRange();
3408
3409 SS.clear();
3410 }
3411
3412 if (MSPropertyAttr) {
3413 Member = HandleMSProperty(S, cast<CXXRecordDecl>(CurContext), Loc, D,
3414 BitWidth, InitStyle, AS, *MSPropertyAttr);
3415 if (!Member)
3416 return nullptr;
3417 isInstField = false;
3418 } else {
3419 Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D,
3420 BitWidth, InitStyle, AS);
3421 if (!Member)
3422 return nullptr;
3423 }
3424
3425 CheckShadowInheritedFields(Loc, Name, cast<CXXRecordDecl>(CurContext));
3426 } else {
3427 Member = HandleDeclarator(S, D, TemplateParameterLists);
3428 if (!Member)
3429 return nullptr;
3430
3431 // Non-instance-fields can't have a bitfield.
3432 if (BitWidth) {
3433 if (Member->isInvalidDecl()) {
3434 // don't emit another diagnostic.
3435 } else if (isa<VarDecl>(Member) || isa<VarTemplateDecl>(Member)) {
3436 // C++ 9.6p3: A bit-field shall not be a static member.
3437 // "static member 'A' cannot be a bit-field"
3438 Diag(Loc, diag::err_static_not_bitfield)
3439 << Name << BitWidth->getSourceRange();
3440 } else if (isa<TypedefDecl>(Member)) {
3441 // "typedef member 'x' cannot be a bit-field"
3442 Diag(Loc, diag::err_typedef_not_bitfield)
3443 << Name << BitWidth->getSourceRange();
3444 } else {
3445 // A function typedef ("typedef int f(); f a;").
3446 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
3447 Diag(Loc, diag::err_not_integral_type_bitfield)
3448 << Name << cast<ValueDecl>(Member)->getType()
3449 << BitWidth->getSourceRange();
3450 }
3451
3452 BitWidth = nullptr;
3453 Member->setInvalidDecl();
3454 }
3455
3456 NamedDecl *NonTemplateMember = Member;
3457 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Member))
3458 NonTemplateMember = FunTmpl->getTemplatedDecl();
3459 else if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(Member))
3460 NonTemplateMember = VarTmpl->getTemplatedDecl();
3461
3462 Member->setAccess(AS);
3463
3464 // If we have declared a member function template or static data member
3465 // template, set the access of the templated declaration as well.
3466 if (NonTemplateMember != Member)
3467 NonTemplateMember->setAccess(AS);
3468
3469 // C++ [temp.deduct.guide]p3:
3470 // A deduction guide [...] for a member class template [shall be
3471 // declared] with the same access [as the template].
3472 if (auto *DG = dyn_cast<CXXDeductionGuideDecl>(NonTemplateMember)) {
3473 auto *TD = DG->getDeducedTemplate();
3474 // Access specifiers are only meaningful if both the template and the
3475 // deduction guide are from the same scope.
3476 if (AS != TD->getAccess() &&
3477 TD->getDeclContext()->getRedeclContext()->Equals(
3478 DG->getDeclContext()->getRedeclContext())) {
3479 Diag(DG->getBeginLoc(), diag::err_deduction_guide_wrong_access);
3480 Diag(TD->getBeginLoc(), diag::note_deduction_guide_template_access)
3481 << TD->getAccess();
3482 const AccessSpecDecl *LastAccessSpec = nullptr;
3483 for (const auto *D : cast<CXXRecordDecl>(CurContext)->decls()) {
3484 if (const auto *AccessSpec = dyn_cast<AccessSpecDecl>(D))
3485 LastAccessSpec = AccessSpec;
3486 }
3487 assert(LastAccessSpec && "differing access with no access specifier")(static_cast<void> (0));
3488 Diag(LastAccessSpec->getBeginLoc(), diag::note_deduction_guide_access)
3489 << AS;
3490 }
3491 }
3492 }
3493
3494 if (VS.isOverrideSpecified())
3495 Member->addAttr(OverrideAttr::Create(Context, VS.getOverrideLoc(),
3496 AttributeCommonInfo::AS_Keyword));
3497 if (VS.isFinalSpecified())
3498 Member->addAttr(FinalAttr::Create(
3499 Context, VS.getFinalLoc(), AttributeCommonInfo::AS_Keyword,
3500 static_cast<FinalAttr::Spelling>(VS.isFinalSpelledSealed())));
3501
3502 if (VS.getLastLocation().isValid()) {
3503 // Update the end location of a method that has a virt-specifiers.
3504 if (CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Member))
3505 MD->setRangeEnd(VS.getLastLocation());
3506 }
3507
3508 CheckOverrideControl(Member);
3509
3510 assert((Name || isInstField) && "No identifier for non-field ?")(static_cast<void> (0));
3511
3512 if (isInstField) {
3513 FieldDecl *FD = cast<FieldDecl>(Member);
3514 FieldCollector->Add(FD);
3515
3516 if (!Diags.isIgnored(diag::warn_unused_private_field, FD->getLocation())) {
3517 // Remember all explicit private FieldDecls that have a name, no side
3518 // effects and are not part of a dependent type declaration.
3519 if (!FD->isImplicit() && FD->getDeclName() &&
3520 FD->getAccess() == AS_private &&
3521 !FD->hasAttr<UnusedAttr>() &&
3522 !FD->getParent()->isDependentContext() &&
3523 !InitializationHasSideEffects(*FD))
3524 UnusedPrivateFields.insert(FD);
3525 }
3526 }
3527
3528 return Member;
3529}
3530
3531namespace {
3532 class UninitializedFieldVisitor
3533 : public EvaluatedExprVisitor<UninitializedFieldVisitor> {
3534 Sema &S;
3535 // List of Decls to generate a warning on. Also remove Decls that become
3536 // initialized.
3537 llvm::SmallPtrSetImpl<ValueDecl*> &Decls;
3538 // List of base classes of the record. Classes are removed after their
3539 // initializers.
3540 llvm::SmallPtrSetImpl<QualType> &BaseClasses;
3541 // Vector of decls to be removed from the Decl set prior to visiting the
3542 // nodes. These Decls may have been initialized in the prior initializer.
3543 llvm::SmallVector<ValueDecl*, 4> DeclsToRemove;
3544 // If non-null, add a note to the warning pointing back to the constructor.
3545 const CXXConstructorDecl *Constructor;
3546 // Variables to hold state when processing an initializer list. When
3547 // InitList is true, special case initialization of FieldDecls matching
3548 // InitListFieldDecl.
3549 bool InitList;
3550 FieldDecl *InitListFieldDecl;
3551 llvm::SmallVector<unsigned, 4> InitFieldIndex;
3552
3553 public:
3554 typedef EvaluatedExprVisitor<UninitializedFieldVisitor> Inherited;
3555 UninitializedFieldVisitor(Sema &S,
3556 llvm::SmallPtrSetImpl<ValueDecl*> &Decls,
3557 llvm::SmallPtrSetImpl<QualType> &BaseClasses)
3558 : Inherited(S.Context), S(S), Decls(Decls), BaseClasses(BaseClasses),
3559 Constructor(nullptr), InitList(false), InitListFieldDecl(nullptr) {}
3560
3561 // Returns true if the use of ME is not an uninitialized use.
3562 bool IsInitListMemberExprInitialized(MemberExpr *ME,
3563 bool CheckReferenceOnly) {
3564 llvm::SmallVector<FieldDecl*, 4> Fields;
3565 bool ReferenceField = false;
3566 while (ME) {
3567 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
3568 if (!FD)
3569 return false;
3570 Fields.push_back(FD);
3571 if (FD->getType()->isReferenceType())
3572 ReferenceField = true;
3573 ME = dyn_cast<MemberExpr>(ME->getBase()->IgnoreParenImpCasts());
3574 }
3575
3576 // Binding a reference to an uninitialized field is not an
3577 // uninitialized use.
3578 if (CheckReferenceOnly && !ReferenceField)
3579 return true;
3580
3581 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
3582 // Discard the first field since it is the field decl that is being
3583 // initialized.
3584 for (auto I = Fields.rbegin() + 1, E = Fields.rend(); I != E; ++I) {
3585 UsedFieldIndex.push_back((*I)->getFieldIndex());
3586 }
3587
3588 for (auto UsedIter = UsedFieldIndex.begin(),
3589 UsedEnd = UsedFieldIndex.end(),
3590 OrigIter = InitFieldIndex.begin(),
3591 OrigEnd = InitFieldIndex.end();
3592 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
3593 if (*UsedIter < *OrigIter)
3594 return true;
3595 if (*UsedIter > *OrigIter)
3596 break;
3597 }
3598
3599 return false;
3600 }
3601
3602 void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly,
3603 bool AddressOf) {
3604 if (isa<EnumConstantDecl>(ME->getMemberDecl()))
3605 return;
3606
3607 // FieldME is the inner-most MemberExpr that is not an anonymous struct
3608 // or union.
3609 MemberExpr *FieldME = ME;
3610
3611 bool AllPODFields = FieldME->getType().isPODType(S.Context);
3612
3613 Expr *Base = ME;
3614 while (MemberExpr *SubME =
3615 dyn_cast<MemberExpr>(Base->IgnoreParenImpCasts())) {
3616
3617 if (isa<VarDecl>(SubME->getMemberDecl()))
3618 return;
3619
3620 if (FieldDecl *FD = dyn_cast<FieldDecl>(SubME->getMemberDecl()))
3621 if (!FD->isAnonymousStructOrUnion())
3622 FieldME = SubME;
3623
3624 if (!FieldME->getType().isPODType(S.Context))
3625 AllPODFields = false;
3626
3627 Base = SubME->getBase();
3628 }
3629
3630 if (!isa<CXXThisExpr>(Base->IgnoreParenImpCasts())) {
3631 Visit(Base);
3632 return;
3633 }
3634
3635 if (AddressOf && AllPODFields)
3636 return;
3637
3638 ValueDecl* FoundVD = FieldME->getMemberDecl();
3639
3640 if (ImplicitCastExpr *BaseCast = dyn_cast<ImplicitCastExpr>(Base)) {
3641 while (isa<ImplicitCastExpr>(BaseCast->getSubExpr())) {
3642 BaseCast = cast<ImplicitCastExpr>(BaseCast->getSubExpr());
3643 }
3644
3645 if (BaseCast->getCastKind() == CK_UncheckedDerivedToBase) {
3646 QualType T = BaseCast->getType();
3647 if (T->isPointerType() &&
3648 BaseClasses.count(T->getPointeeType())) {
3649 S.Diag(FieldME->getExprLoc(), diag::warn_base_class_is_uninit)
3650 << T->getPointeeType() << FoundVD;
3651 }
3652 }
3653 }
3654
3655 if (!Decls.count(FoundVD))
3656 return;
3657
3658 const bool IsReference = FoundVD->getType()->isReferenceType();
3659
3660 if (InitList && !AddressOf && FoundVD == InitListFieldDecl) {
3661 // Special checking for initializer lists.
3662 if (IsInitListMemberExprInitialized(ME, CheckReferenceOnly)) {
3663 return;
3664 }
3665 } else {
3666 // Prevent double warnings on use of unbounded references.
3667 if (CheckReferenceOnly && !IsReference)
3668 return;
3669 }
3670
3671 unsigned diag = IsReference
3672 ? diag::warn_reference_field_is_uninit
3673 : diag::warn_field_is_uninit;
3674 S.Diag(FieldME->getExprLoc(), diag) << FoundVD;
3675 if (Constructor)
3676 S.Diag(Constructor->getLocation(),
3677 diag::note_uninit_in_this_constructor)
3678 << (Constructor->isDefaultConstructor() && Constructor->isImplicit());
3679
3680 }
3681
3682 void HandleValue(Expr *E, bool AddressOf) {
3683 E = E->IgnoreParens();
3684
3685 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
3686 HandleMemberExpr(ME, false /*CheckReferenceOnly*/,
3687 AddressOf /*AddressOf*/);
3688 return;
3689 }
3690
3691 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
3692 Visit(CO->getCond());
3693 HandleValue(CO->getTrueExpr(), AddressOf);
3694 HandleValue(CO->getFalseExpr(), AddressOf);
3695 return;
3696 }
3697
3698 if (BinaryConditionalOperator *BCO =
3699 dyn_cast<BinaryConditionalOperator>(E)) {
3700 Visit(BCO->getCond());
3701 HandleValue(BCO->getFalseExpr(), AddressOf);
3702 return;
3703 }
3704
3705 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
3706 HandleValue(OVE->getSourceExpr(), AddressOf);
3707 return;
3708 }
3709
3710 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
3711 switch (BO->getOpcode()) {
3712 default:
3713 break;
3714 case(BO_PtrMemD):
3715 case(BO_PtrMemI):
3716 HandleValue(BO->getLHS(), AddressOf);
3717 Visit(BO->getRHS());
3718 return;
3719 case(BO_Comma):
3720 Visit(BO->getLHS());
3721 HandleValue(BO->getRHS(), AddressOf);
3722 return;
3723 }
3724 }
3725
3726 Visit(E);
3727 }
3728
3729 void CheckInitListExpr(InitListExpr *ILE) {
3730 InitFieldIndex.push_back(0);
3731 for (auto Child : ILE->children()) {
3732 if (InitListExpr *SubList = dyn_cast<InitListExpr>(Child)) {
3733 CheckInitListExpr(SubList);
3734 } else {
3735 Visit(Child);
3736 }
3737 ++InitFieldIndex.back();
3738 }
3739 InitFieldIndex.pop_back();
3740 }
3741
3742 void CheckInitializer(Expr *E, const CXXConstructorDecl *FieldConstructor,
3743 FieldDecl *Field, const Type *BaseClass) {
3744 // Remove Decls that may have been initialized in the previous
3745 // initializer.
3746 for (ValueDecl* VD : DeclsToRemove)
3747 Decls.erase(VD);
3748 DeclsToRemove.clear();
3749
3750 Constructor = FieldConstructor;
3751 InitListExpr *ILE = dyn_cast<InitListExpr>(E);
3752
3753 if (ILE && Field) {
3754 InitList = true;
3755 InitListFieldDecl = Field;
3756 InitFieldIndex.clear();
3757 CheckInitListExpr(ILE);
3758 } else {
3759 InitList = false;
3760 Visit(E);
3761 }
3762
3763 if (Field)
3764 Decls.erase(Field);
3765 if (BaseClass)
3766 BaseClasses.erase(BaseClass->getCanonicalTypeInternal());
3767 }
3768
3769 void VisitMemberExpr(MemberExpr *ME) {
3770 // All uses of unbounded reference fields will warn.
3771 HandleMemberExpr(ME, true /*CheckReferenceOnly*/, false /*AddressOf*/);
3772 }
3773
3774 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
3775 if (E->getCastKind() == CK_LValueToRValue) {
3776 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3777 return;
3778 }
3779
3780 Inherited::VisitImplicitCastExpr(E);
3781 }
3782
3783 void VisitCXXConstructExpr(CXXConstructExpr *E) {
3784 if (E->getConstructor()->isCopyConstructor()) {
3785 Expr *ArgExpr = E->getArg(0);
3786 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
3787 if (ILE->getNumInits() == 1)
3788 ArgExpr = ILE->getInit(0);
3789 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
3790 if (ICE->getCastKind() == CK_NoOp)
3791 ArgExpr = ICE->getSubExpr();
3792 HandleValue(ArgExpr, false /*AddressOf*/);
3793 return;
3794 }
3795 Inherited::VisitCXXConstructExpr(E);
3796 }
3797
3798 void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
3799 Expr *Callee = E->getCallee();
3800 if (isa<MemberExpr>(Callee)) {
3801 HandleValue(Callee, false /*AddressOf*/);
3802 for (auto Arg : E->arguments())
3803 Visit(Arg);
3804 return;
3805 }
3806
3807 Inherited::VisitCXXMemberCallExpr(E);
3808 }
3809
3810 void VisitCallExpr(CallExpr *E) {
3811 // Treat std::move as a use.
3812 if (E->isCallToStdMove()) {
3813 HandleValue(E->getArg(0), /*AddressOf=*/false);
3814 return;
3815 }
3816
3817 Inherited::VisitCallExpr(E);
3818 }
3819
3820 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
3821 Expr *Callee = E->getCallee();
3822
3823 if (isa<UnresolvedLookupExpr>(Callee))
3824 return Inherited::VisitCXXOperatorCallExpr(E);
3825
3826 Visit(Callee);
3827 for (auto Arg : E->arguments())
3828 HandleValue(Arg->IgnoreParenImpCasts(), false /*AddressOf*/);
3829 }
3830
3831 void VisitBinaryOperator(BinaryOperator *E) {
3832 // If a field assignment is detected, remove the field from the
3833 // uninitiailized field set.
3834 if (E->getOpcode() == BO_Assign)
3835 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getLHS()))
3836 if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3837 if (!FD->getType()->isReferenceType())
3838 DeclsToRemove.push_back(FD);
3839
3840 if (E->isCompoundAssignmentOp()) {
3841 HandleValue(E->getLHS(), false /*AddressOf*/);
3842 Visit(E->getRHS());
3843 return;
3844 }
3845
3846 Inherited::VisitBinaryOperator(E);
3847 }
3848
3849 void VisitUnaryOperator(UnaryOperator *E) {
3850 if (E->isIncrementDecrementOp()) {
3851 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3852 return;
3853 }
3854 if (E->getOpcode() == UO_AddrOf) {
3855 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getSubExpr())) {
3856 HandleValue(ME->getBase(), true /*AddressOf*/);
3857 return;
3858 }
3859 }
3860
3861 Inherited::VisitUnaryOperator(E);
3862 }
3863 };
3864
3865 // Diagnose value-uses of fields to initialize themselves, e.g.
3866 // foo(foo)
3867 // where foo is not also a parameter to the constructor.
3868 // Also diagnose across field uninitialized use such as
3869 // x(y), y(x)
3870 // TODO: implement -Wuninitialized and fold this into that framework.
3871 static void DiagnoseUninitializedFields(
3872 Sema &SemaRef, const CXXConstructorDecl *Constructor) {
3873
3874 if (SemaRef.getDiagnostics().isIgnored(diag::warn_field_is_uninit,
3875 Constructor->getLocation())) {
3876 return;
3877 }
3878
3879 if (Constructor->isInvalidDecl())
3880 return;
3881
3882 const CXXRecordDecl *RD = Constructor->getParent();
3883
3884 if (RD->isDependentContext())
3885 return;
3886
3887 // Holds fields that are uninitialized.
3888 llvm::SmallPtrSet<ValueDecl*, 4> UninitializedFields;
3889
3890 // At the beginning, all fields are uninitialized.
3891 for (auto *I : RD->decls()) {
3892 if (auto *FD = dyn_cast<FieldDecl>(I)) {
3893 UninitializedFields.insert(FD);
3894 } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(I)) {
3895 UninitializedFields.insert(IFD->getAnonField());
3896 }
3897 }
3898
3899 llvm::SmallPtrSet<QualType, 4> UninitializedBaseClasses;
3900 for (auto I : RD->bases())
3901 UninitializedBaseClasses.insert(I.getType().getCanonicalType());
3902
3903 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3904 return;
3905
3906 UninitializedFieldVisitor UninitializedChecker(SemaRef,
3907 UninitializedFields,
3908 UninitializedBaseClasses);
3909
3910 for (const auto *FieldInit : Constructor->inits()) {
3911 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3912 break;
3913
3914 Expr *InitExpr = FieldInit->getInit();
3915 if (!InitExpr)
3916 continue;
3917
3918 if (CXXDefaultInitExpr *Default =
3919 dyn_cast<CXXDefaultInitExpr>(InitExpr)) {
3920 InitExpr = Default->getExpr();
3921 if (!InitExpr)
3922 continue;
3923 // In class initializers will point to the constructor.
3924 UninitializedChecker.CheckInitializer(InitExpr, Constructor,
3925 FieldInit->getAnyMember(),
3926 FieldInit->getBaseClass());
3927 } else {
3928 UninitializedChecker.CheckInitializer(InitExpr, nullptr,
3929 FieldInit->getAnyMember(),
3930 FieldInit->getBaseClass());
3931 }
3932 }
3933 }
3934} // namespace
3935
3936/// Enter a new C++ default initializer scope. After calling this, the
3937/// caller must call \ref ActOnFinishCXXInClassMemberInitializer, even if
3938/// parsing or instantiating the initializer failed.
3939void Sema::ActOnStartCXXInClassMemberInitializer() {
3940 // Create a synthetic function scope to represent the call to the constructor
3941 // that notionally surrounds a use of this initializer.
3942 PushFunctionScope();
3943}
3944
3945void Sema::ActOnStartTrailingRequiresClause(Scope *S, Declarator &D) {
3946 if (!D.isFunctionDeclarator())
3947 return;
3948 auto &FTI = D.getFunctionTypeInfo();
3949 if (!FTI.Params)
3950 return;
3951 for (auto &Param : ArrayRef<DeclaratorChunk::ParamInfo>(FTI.Params,
3952 FTI.NumParams)) {
3953 auto *ParamDecl = cast<NamedDecl>(Param.Param);
3954 if (ParamDecl->getDeclName())
3955 PushOnScopeChains(ParamDecl, S, /*AddToContext=*/false);
3956 }
3957}
3958
3959ExprResult Sema::ActOnFinishTrailingRequiresClause(ExprResult ConstraintExpr) {
3960 return ActOnRequiresClause(ConstraintExpr);
3961}
3962
3963ExprResult Sema::ActOnRequiresClause(ExprResult ConstraintExpr) {
3964 if (ConstraintExpr.isInvalid())
3965 return ExprError();
3966
3967 ConstraintExpr = CorrectDelayedTyposInExpr(ConstraintExpr);
3968 if (ConstraintExpr.isInvalid())
3969 return ExprError();
3970
3971 if (DiagnoseUnexpandedParameterPack(ConstraintExpr.get(),
3972 UPPC_RequiresClause))
3973 return ExprError();
3974
3975 return ConstraintExpr;
3976}
3977
3978/// This is invoked after parsing an in-class initializer for a
3979/// non-static C++ class member, and after instantiating an in-class initializer
3980/// in a class template. Such actions are deferred until the class is complete.
3981void Sema::ActOnFinishCXXInClassMemberInitializer(Decl *D,
3982 SourceLocation InitLoc,
3983 Expr *InitExpr) {
3984 // Pop the notional constructor scope we created earlier.
3985 PopFunctionScopeInfo(nullptr, D);
3986
3987 FieldDecl *FD = dyn_cast<FieldDecl>(D);
3988 assert((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) &&(static_cast<void> (0))
3989 "must set init style when field is created")(static_cast<void> (0));
3990
3991 if (!InitExpr) {
3992 D->setInvalidDecl();
3993 if (FD)
3994 FD->removeInClassInitializer();
3995 return;
3996 }
3997
3998 if (DiagnoseUnexpandedParameterPack(InitExpr, UPPC_Initializer)) {
3999 FD->setInvalidDecl();
4000 FD->removeInClassInitializer();
4001 return;
4002 }
4003
4004 ExprResult Init = InitExpr;
4005 if (!FD->getType()->isDependentType() && !InitExpr->isTypeDependent()) {
4006 InitializedEntity Entity =
4007 InitializedEntity::InitializeMemberFromDefaultMemberInitializer(FD);
4008 InitializationKind Kind =
4009 FD->getInClassInitStyle() == ICIS_ListInit
4010 ? InitializationKind::CreateDirectList(InitExpr->getBeginLoc(),
4011 InitExpr->getBeginLoc(),
4012 InitExpr->getEndLoc())
4013 : InitializationKind::CreateCopy(InitExpr->getBeginLoc(), InitLoc);
4014 InitializationSequence Seq(*this, Entity, Kind, InitExpr);
4015 Init = Seq.Perform(*this, Entity, Kind, InitExpr);
4016 if (Init.isInvalid()) {
4017 FD->setInvalidDecl();
4018 return;
4019 }
4020 }
4021
4022 // C++11 [class.base.init]p7:
4023 // The initialization of each base and member constitutes a
4024 // full-expression.
4025 Init = ActOnFinishFullExpr(Init.get(), InitLoc, /*DiscardedValue*/ false);
4026 if (Init.isInvalid()) {
4027 FD->setInvalidDecl();
4028 return;
4029 }
4030
4031 InitExpr = Init.get();
4032
4033 FD->setInClassInitializer(InitExpr);
4034}
4035
4036/// Find the direct and/or virtual base specifiers that
4037/// correspond to the given base type, for use in base initialization
4038/// within a constructor.
4039static bool FindBaseInitializer(Sema &SemaRef,
4040 CXXRecordDecl *ClassDecl,
4041 QualType BaseType,
4042 const CXXBaseSpecifier *&DirectBaseSpec,
4043 const CXXBaseSpecifier *&VirtualBaseSpec) {
4044 // First, check for a direct base class.
4045 DirectBaseSpec = nullptr;
4046 for (const auto &Base : ClassDecl->bases()) {
4047 if (SemaRef.Context.hasSameUnqualifiedType(BaseType, Base.getType())) {
4048 // We found a direct base of this type. That's what we're
4049 // initializing.
4050 DirectBaseSpec = &Base;
4051 break;
4052 }
4053 }
4054
4055 // Check for a virtual base class.
4056 // FIXME: We might be able to short-circuit this if we know in advance that
4057 // there are no virtual bases.
4058 VirtualBaseSpec = nullptr;
4059 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) {
4060 // We haven't found a base yet; search the class hierarchy for a
4061 // virtual base class.
4062 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
4063 /*DetectVirtual=*/false);
4064 if (SemaRef.IsDerivedFrom(ClassDecl->getLocation(),
4065 SemaRef.Context.getTypeDeclType(ClassDecl),
4066 BaseType, Paths)) {
4067 for (CXXBasePaths::paths_iterator Path = Paths.begin();
4068 Path != Paths.end(); ++Path) {
4069 if (Path->back().Base->isVirtual()) {
4070 VirtualBaseSpec = Path->back().Base;
4071 break;
4072 }
4073 }
4074 }
4075 }
4076
4077 return DirectBaseSpec || VirtualBaseSpec;
4078}
4079
4080/// Handle a C++ member initializer using braced-init-list syntax.
4081MemInitResult
4082Sema::ActOnMemInitializer(Decl *ConstructorD,
4083 Scope *S,
4084 CXXScopeSpec &SS,
4085 IdentifierInfo *MemberOrBase,
4086 ParsedType TemplateTypeTy,
4087 const DeclSpec &DS,
4088 SourceLocation IdLoc,
4089 Expr *InitList,
4090 SourceLocation EllipsisLoc) {
4091 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
4092 DS, IdLoc, InitList,
4093 EllipsisLoc);
4094}
4095
4096/// Handle a C++ member initializer using parentheses syntax.
4097MemInitResult
4098Sema::ActOnMemInitializer(Decl *ConstructorD,
4099 Scope *S,
4100 CXXScopeSpec &SS,
4101 IdentifierInfo *MemberOrBase,
4102 ParsedType TemplateTypeTy,
4103 const DeclSpec &DS,
4104 SourceLocation IdLoc,
4105 SourceLocation LParenLoc,
4106 ArrayRef<Expr *> Args,
4107 SourceLocation RParenLoc,
4108 SourceLocation EllipsisLoc) {
4109 Expr *List = ParenListExpr::Create(Context, LParenLoc, Args, RParenLoc);
4110 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
4111 DS, IdLoc, List, EllipsisLoc);
4112}
4113
4114namespace {
4115
4116// Callback to only accept typo corrections that can be a valid C++ member
4117// intializer: either a non-static field member or a base class.
4118class MemInitializerValidatorCCC final : public CorrectionCandidateCallback {
4119public:
4120 explicit MemInitializerValidatorCCC(CXXRecordDecl *ClassDecl)
4121 : ClassDecl(ClassDecl) {}
4122
4123 bool ValidateCandidate(const TypoCorrection &candidate) override {
4124 if (NamedDecl *ND = candidate.getCorrectionDecl()) {
4125 if (FieldDecl *Member = dyn_cast<FieldDecl>(ND))
4126 return Member->getDeclContext()->getRedeclContext()->Equals(ClassDecl);
4127 return isa<TypeDecl>(ND);
4128 }
4129 return false;
4130 }
4131
4132 std::unique_ptr<CorrectionCandidateCallback> clone() override {
4133 return std::make_unique<MemInitializerValidatorCCC>(*this);
4134 }
4135
4136private:
4137 CXXRecordDecl *ClassDecl;
4138};
4139
4140}
4141
4142ValueDecl *Sema::tryLookupCtorInitMemberDecl(CXXRecordDecl *ClassDecl,
4143 CXXScopeSpec &SS,
4144 ParsedType TemplateTypeTy,
4145 IdentifierInfo *MemberOrBase) {
4146 if (SS.getScopeRep() || TemplateTypeTy)
4147 return nullptr;
4148 for (auto *D : ClassDecl->lookup(MemberOrBase))
4149 if (isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D))
4150 return cast<ValueDecl>(D);
4151 return nullptr;
4152}
4153
4154/// Handle a C++ member initializer.
4155MemInitResult
4156Sema::BuildMemInitializer(Decl *ConstructorD,
4157 Scope *S,
4158 CXXScopeSpec &SS,
4159 IdentifierInfo *MemberOrBase,
4160 ParsedType TemplateTypeTy,
4161 const DeclSpec &DS,
4162 SourceLocation IdLoc,
4163 Expr *Init,
4164 SourceLocation EllipsisLoc) {
4165 ExprResult Res = CorrectDelayedTyposInExpr(Init, /*InitDecl=*/nullptr,
4166 /*RecoverUncorrectedTypos=*/true);
4167 if (!Res.isUsable())
4168 return true;
4169 Init = Res.get();
4170
4171 if (!ConstructorD)
4172 return true;
4173
4174 AdjustDeclIfTemplate(ConstructorD);
4175
4176 CXXConstructorDecl *Constructor
4177 = dyn_cast<CXXConstructorDecl>(ConstructorD);
4178 if (!Constructor) {
4179 // The user wrote a constructor initializer on a function that is
4180 // not a C++ constructor. Ignore the error for now, because we may
4181 // have more member initializers coming; we'll diagnose it just
4182 // once in ActOnMemInitializers.
4183 return true;
4184 }
4185
4186 CXXRecordDecl *ClassDecl = Constructor->getParent();
4187
4188 // C++ [class.base.init]p2:
4189 // Names in a mem-initializer-id are looked up in the scope of the
4190 // constructor's class and, if not found in that scope, are looked
4191 // up in the scope containing the constructor's definition.
4192 // [Note: if the constructor's class contains a member with the
4193 // same name as a direct or virtual base class of the class, a
4194 // mem-initializer-id naming the member or base class and composed
4195 // of a single identifier refers to the class member. A
4196 // mem-initializer-id for the hidden base class may be specified
4197 // using a qualified name. ]
4198
4199 // Look for a member, first.
4200 if (ValueDecl *Member = tryLookupCtorInitMemberDecl(
4201 ClassDecl, SS, TemplateTypeTy, MemberOrBase)) {
4202 if (EllipsisLoc.isValid())
4203 Diag(EllipsisLoc, diag::err_pack_expansion_member_init)
4204 << MemberOrBase
4205 << SourceRange(IdLoc, Init->getSourceRange().getEnd());
4206
4207 return BuildMemberInitializer(Member, Init, IdLoc);
4208 }
4209 // It didn't name a member, so see if it names a class.
4210 QualType BaseType;
4211 TypeSourceInfo *TInfo = nullptr;
4212
4213 if (TemplateTypeTy) {
4214 BaseType = GetTypeFromParser(TemplateTypeTy, &TInfo);
4215 if (BaseType.isNull())
4216 return true;
4217 } else if (DS.getTypeSpecType() == TST_decltype) {
4218 BaseType = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
4219 } else if (DS.getTypeSpecType() == TST_decltype_auto) {
4220 Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
4221 return true;
4222 } else {
4223 LookupResult R(*this, MemberOrBase, IdLoc, LookupOrdinaryName);
4224 LookupParsedName(R, S, &SS);
4225
4226 TypeDecl *TyD = R.getAsSingle<TypeDecl>();
4227 if (!TyD) {
4228 if (R.isAmbiguous()) return true;
4229
4230 // We don't want access-control diagnostics here.
4231 R.suppressDiagnostics();
4232
4233 if (SS.isSet() && isDependentScopeSpecifier(SS)) {
4234 bool NotUnknownSpecialization = false;
4235 DeclContext *DC = computeDeclContext(SS, false);
4236 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(DC))
4237 NotUnknownSpecialization = !Record->hasAnyDependentBases();
4238
4239 if (!NotUnknownSpecialization) {
4240 // When the scope specifier can refer to a member of an unknown
4241 // specialization, we take it as a type name.
4242 BaseType = CheckTypenameType(ETK_None, SourceLocation(),
4243 SS.getWithLocInContext(Context),
4244 *MemberOrBase, IdLoc);
4245 if (BaseType.isNull())
4246 return true;
4247
4248 TInfo = Context.CreateTypeSourceInfo(BaseType);
4249 DependentNameTypeLoc TL =
4250 TInfo->getTypeLoc().castAs<DependentNameTypeLoc>();
4251 if (!TL.isNull()) {
4252 TL.setNameLoc(IdLoc);
4253 TL.setElaboratedKeywordLoc(SourceLocation());
4254 TL.setQualifierLoc(SS.getWithLocInContext(Context));
4255 }
4256
4257 R.clear();
4258 R.setLookupName(MemberOrBase);
4259 }
4260 }
4261
4262 // If no results were found, try to correct typos.
4263 TypoCorrection Corr;
4264 MemInitializerValidatorCCC CCC(ClassDecl);
4265 if (R.empty() && BaseType.isNull() &&
4266 (Corr = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
4267 CCC, CTK_ErrorRecovery, ClassDecl))) {
4268 if (FieldDecl *Member = Corr.getCorrectionDeclAs<FieldDecl>()) {
4269 // We have found a non-static data member with a similar
4270 // name to what was typed; complain and initialize that
4271 // member.
4272 diagnoseTypo(Corr,
4273 PDiag(diag::err_mem_init_not_member_or_class_suggest)
4274 << MemberOrBase << true);
4275 return BuildMemberInitializer(Member, Init, IdLoc);
4276 } else if (TypeDecl *Type = Corr.getCorrectionDeclAs<TypeDecl>()) {
4277 const CXXBaseSpecifier *DirectBaseSpec;
4278 const CXXBaseSpecifier *VirtualBaseSpec;
4279 if (FindBaseInitializer(*this, ClassDecl,
4280 Context.getTypeDeclType(Type),
4281 DirectBaseSpec, VirtualBaseSpec)) {
4282 // We have found a direct or virtual base class with a
4283 // similar name to what was typed; complain and initialize
4284 // that base class.
4285 diagnoseTypo(Corr,
4286 PDiag(diag::err_mem_init_not_member_or_class_suggest)
4287 << MemberOrBase << false,
4288 PDiag() /*Suppress note, we provide our own.*/);
4289
4290 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec ? DirectBaseSpec
4291 : VirtualBaseSpec;
4292 Diag(BaseSpec->getBeginLoc(), diag::note_base_class_specified_here)
4293 << BaseSpec->getType() << BaseSpec->getSourceRange();
4294
4295 TyD = Type;
4296 }
4297 }
4298 }
4299
4300 if (!TyD && BaseType.isNull()) {
4301 Diag(IdLoc, diag::err_mem_init_not_member_or_class)
4302 << MemberOrBase << SourceRange(IdLoc,Init->getSourceRange().getEnd());
4303 return true;
4304 }
4305 }
4306
4307 if (BaseType.isNull()) {
4308 BaseType = Context.getTypeDeclType(TyD);
4309 MarkAnyDeclReferenced(TyD->getLocation(), TyD, /*OdrUse=*/false);
4310 if (SS.isSet()) {
4311 BaseType = Context.getElaboratedType(ETK_None, SS.getScopeRep(),
4312 BaseType);
4313 TInfo = Context.CreateTypeSourceInfo(BaseType);
4314 ElaboratedTypeLoc TL = TInfo->getTypeLoc().castAs<ElaboratedTypeLoc>();
4315 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
4316 TL.setElaboratedKeywordLoc(SourceLocation());
4317 TL.setQualifierLoc(SS.getWithLocInContext(Context));
4318 }
4319 }
4320 }
4321
4322 if (!TInfo)
4323 TInfo = Context.getTrivialTypeSourceInfo(BaseType, IdLoc);
4324
4325 return BuildBaseInitializer(BaseType, TInfo, Init, ClassDecl, EllipsisLoc);
4326}
4327
4328MemInitResult
4329Sema::BuildMemberInitializer(ValueDecl *Member, Expr *Init,
4330 SourceLocation IdLoc) {
4331 FieldDecl *DirectMember = dyn_cast<FieldDecl>(Member);
4332 IndirectFieldDecl *IndirectMember = dyn_cast<IndirectFieldDecl>(Member);
4333 assert((DirectMember || IndirectMember) &&(static_cast<void> (0))
4334 "Member must be a FieldDecl or IndirectFieldDecl")(static_cast<void> (0));
4335
4336 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
4337 return true;
4338
4339 if (Member->isInvalidDecl())
4340 return true;
4341
4342 MultiExprArg Args;
4343 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4344 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4345 } else if (InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
4346 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
4347 } else {
4348 // Template instantiation doesn't reconstruct ParenListExprs for us.
4349 Args = Init;
4350 }
4351
4352 SourceRange InitRange = Init->getSourceRange();
4353
4354 if (Member->getType()->isDependentType() || Init->isTypeDependent()) {
4355 // Can't check initialization for a member of dependent type or when
4356 // any of the arguments are type-dependent expressions.
4357 DiscardCleanupsInEvaluationContext();
4358 } else {
4359 bool InitList = false;
4360 if (isa<InitListExpr>(Init)) {
4361 InitList = true;
4362 Args = Init;
4363 }
4364
4365 // Initialize the member.
4366 InitializedEntity MemberEntity =
4367 DirectMember ? InitializedEntity::InitializeMember(DirectMember, nullptr)
4368 : InitializedEntity::InitializeMember(IndirectMember,
4369 nullptr);
4370 InitializationKind Kind =
4371 InitList ? InitializationKind::CreateDirectList(
4372 IdLoc, Init->getBeginLoc(), Init->getEndLoc())
4373 : InitializationKind::CreateDirect(IdLoc, InitRange.getBegin(),
4374 InitRange.getEnd());
4375
4376 InitializationSequence InitSeq(*this, MemberEntity, Kind, Args);
4377 ExprResult MemberInit = InitSeq.Perform(*this, MemberEntity, Kind, Args,
4378 nullptr);
4379 if (!MemberInit.isInvalid()) {
4380 // C++11 [class.base.init]p7:
4381 // The initialization of each base and member constitutes a
4382 // full-expression.
4383 MemberInit = ActOnFinishFullExpr(MemberInit.get(), InitRange.getBegin(),
4384 /*DiscardedValue*/ false);
4385 }
4386
4387 if (MemberInit.isInvalid()) {
4388 // Args were sensible expressions but we couldn't initialize the member
4389 // from them. Preserve them in a RecoveryExpr instead.
4390 Init = CreateRecoveryExpr(InitRange.getBegin(), InitRange.getEnd(), Args,
4391 Member->getType())
4392 .get();
4393 if (!Init)
4394 return true;
4395 } else {
4396 Init = MemberInit.get();
4397 }
4398 }
4399
4400 if (DirectMember) {
4401 return new (Context) CXXCtorInitializer(Context, DirectMember, IdLoc,
4402 InitRange.getBegin(), Init,
4403 InitRange.getEnd());
4404 } else {
4405 return new (Context) CXXCtorInitializer(Context, IndirectMember, IdLoc,
4406 InitRange.getBegin(), Init,
4407 InitRange.getEnd());
4408 }
4409}
4410
4411MemInitResult
4412Sema::BuildDelegatingInitializer(TypeSourceInfo *TInfo, Expr *Init,
4413 CXXRecordDecl *ClassDecl) {
4414 SourceLocation NameLoc = TInfo->getTypeLoc().getLocalSourceRange().getBegin();
4415 if (!LangOpts.CPlusPlus11)
4416 return Diag(NameLoc, diag::err_delegating_ctor)
4417 << TInfo->getTypeLoc().getLocalSourceRange();
4418 Diag(NameLoc, diag::warn_cxx98_compat_delegating_ctor);
4419
4420 bool InitList = true;
4421 MultiExprArg Args = Init;
4422 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4423 InitList = false;
4424 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4425 }
4426
4427 SourceRange InitRange = Init->getSourceRange();
4428 // Initialize the object.
4429 InitializedEntity DelegationEntity = InitializedEntity::InitializeDelegation(
4430 QualType(ClassDecl->getTypeForDecl(), 0));
4431 InitializationKind Kind =
4432 InitList ? InitializationKind::CreateDirectList(
4433 NameLoc, Init->getBeginLoc(), Init->getEndLoc())
4434 : InitializationKind::CreateDirect(NameLoc, InitRange.getBegin(),
4435 InitRange.getEnd());
4436 InitializationSequence InitSeq(*this, DelegationEntity, Kind, Args);
4437 ExprResult DelegationInit = InitSeq.Perform(*this, DelegationEntity, Kind,
4438 Args, nullptr);
4439 if (!DelegationInit.isInvalid()) {
4440 assert((DelegationInit.get()->containsErrors() ||(static_cast<void> (0))
4441 cast<CXXConstructExpr>(DelegationInit.get())->getConstructor()) &&(static_cast<void> (0))
4442 "Delegating constructor with no target?")(static_cast<void> (0));
4443
4444 // C++11 [class.base.init]p7:
4445 // The initialization of each base and member constitutes a
4446 // full-expression.
4447 DelegationInit = ActOnFinishFullExpr(
4448 DelegationInit.get(), InitRange.getBegin(), /*DiscardedValue*/ false);
4449 }
4450
4451 if (DelegationInit.isInvalid()) {
4452 DelegationInit =
4453 CreateRecoveryExpr(InitRange.getBegin(), InitRange.getEnd(), Args,
4454 QualType(ClassDecl->getTypeForDecl(), 0));
4455 if (DelegationInit.isInvalid())
4456 return true;
4457 } else {
4458 // If we are in a dependent context, template instantiation will
4459 // perform this type-checking again. Just save the arguments that we
4460 // received in a ParenListExpr.
4461 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4462 // of the information that we have about the base
4463 // initializer. However, deconstructing the ASTs is a dicey process,
4464 // and this approach is far more likely to get the corner cases right.
4465 if (CurContext->isDependentContext())
4466 DelegationInit = Init;
4467 }
4468
4469 return new (Context) CXXCtorInitializer(Context, TInfo, InitRange.getBegin(),
4470 DelegationInit.getAs<Expr>(),
4471 InitRange.getEnd());
4472}
4473
4474MemInitResult
4475Sema::BuildBaseInitializer(QualType BaseType, TypeSourceInfo *BaseTInfo,
4476 Expr *Init, CXXRecordDecl *ClassDecl,
4477 SourceLocation EllipsisLoc) {
4478 SourceLocation BaseLoc
4479 = BaseTInfo->getTypeLoc().getLocalSourceRange().getBegin();
4480
4481 if (!BaseType->isDependentType() && !BaseType->isRecordType())
4482 return Diag(BaseLoc, diag::err_base_init_does_not_name_class)
4483 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
4484
4485 // C++ [class.base.init]p2:
4486 // [...] Unless the mem-initializer-id names a nonstatic data
4487 // member of the constructor's class or a direct or virtual base
4488 // of that class, the mem-initializer is ill-formed. A
4489 // mem-initializer-list can initialize a base class using any
4490 // name that denotes that base class type.
4491
4492 // We can store the initializers in "as-written" form and delay analysis until
4493 // instantiation if the constructor is dependent. But not for dependent
4494 // (broken) code in a non-template! SetCtorInitializers does not expect this.
4495 bool Dependent = CurContext->isDependentContext() &&
4496 (BaseType->isDependentType() || Init->isTypeDependent());
4497
4498 SourceRange InitRange = Init->getSourceRange();
4499 if (EllipsisLoc.isValid()) {
4500 // This is a pack expansion.
4501 if (!BaseType->containsUnexpandedParameterPack()) {
4502 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
4503 << SourceRange(BaseLoc, InitRange.getEnd());
4504
4505 EllipsisLoc = SourceLocation();
4506 }
4507 } else {
4508 // Check for any unexpanded parameter packs.
4509 if (DiagnoseUnexpandedParameterPack(BaseLoc, BaseTInfo, UPPC_Initializer))
4510 return true;
4511
4512 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
4513 return true;
4514 }
4515
4516 // Check for direct and virtual base classes.
4517 const CXXBaseSpecifier *DirectBaseSpec = nullptr;
4518 const CXXBaseSpecifier *VirtualBaseSpec = nullptr;
4519 if (!Dependent) {
4520 if (Context.hasSameUnqualifiedType(QualType(ClassDecl->getTypeForDecl(),0),
4521 BaseType))
4522 return BuildDelegatingInitializer(BaseTInfo, Init, ClassDecl);
4523
4524 FindBaseInitializer(*this, ClassDecl, BaseType, DirectBaseSpec,
4525 VirtualBaseSpec);
4526
4527 // C++ [base.class.init]p2:
4528 // Unless the mem-initializer-id names a nonstatic data member of the
4529 // constructor's class or a direct or virtual base of that class, the
4530 // mem-initializer is ill-formed.
4531 if (!DirectBaseSpec && !VirtualBaseSpec) {
4532 // If the class has any dependent bases, then it's possible that
4533 // one of those types will resolve to the same type as
4534 // BaseType. Therefore, just treat this as a dependent base
4535 // class initialization. FIXME: Should we try to check the
4536 // initialization anyway? It seems odd.
4537 if (ClassDecl->hasAnyDependentBases())
4538 Dependent = true;
4539 else
4540 return Diag(BaseLoc, diag::err_not_direct_base_or_virtual)
4541 << BaseType << Context.getTypeDeclType(ClassDecl)
4542 << BaseTInfo->getTypeLoc().getLocalSourceRange();
4543 }
4544 }
4545
4546 if (Dependent) {
4547 DiscardCleanupsInEvaluationContext();
4548
4549 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4550 /*IsVirtual=*/false,
4551 InitRange.getBegin(), Init,
4552 InitRange.getEnd(), EllipsisLoc);
4553 }
4554
4555 // C++ [base.class.init]p2:
4556 // If a mem-initializer-id is ambiguous because it designates both
4557 // a direct non-virtual base class and an inherited virtual base
4558 // class, the mem-initializer is ill-formed.
4559 if (DirectBaseSpec && VirtualBaseSpec)
4560 return Diag(BaseLoc, diag::err_base_init_direct_and_virtual)
4561 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
4562
4563 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec;
4564 if (!BaseSpec)
4565 BaseSpec = VirtualBaseSpec;
4566
4567 // Initialize the base.
4568 bool InitList = true;
4569 MultiExprArg Args = Init;
4570 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4571 InitList = false;
4572 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4573 }
4574
4575 InitializedEntity BaseEntity =
4576 InitializedEntity::InitializeBase(Context, BaseSpec, VirtualBaseSpec);
4577 InitializationKind Kind =
4578 InitList ? InitializationKind::CreateDirectList(BaseLoc)
4579 : InitializationKind::CreateDirect(BaseLoc, InitRange.getBegin(),
4580 InitRange.getEnd());
4581 InitializationSequence InitSeq(*this, BaseEntity, Kind, Args);
4582 ExprResult BaseInit = InitSeq.Perform(*this, BaseEntity, Kind, Args, nullptr);
4583 if (!BaseInit.isInvalid()) {
4584 // C++11 [class.base.init]p7:
4585 // The initialization of each base and member constitutes a
4586 // full-expression.
4587 BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin(),
4588 /*DiscardedValue*/ false);
4589 }
4590
4591 if (BaseInit.isInvalid()) {
4592 BaseInit = CreateRecoveryExpr(InitRange.getBegin(), InitRange.getEnd(),
4593 Args, BaseType);
4594 if (BaseInit.isInvalid())
4595 return true;
4596 } else {
4597 // If we are in a dependent context, template instantiation will
4598 // perform this type-checking again. Just save the arguments that we
4599 // received in a ParenListExpr.
4600 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4601 // of the information that we have about the base
4602 // initializer. However, deconstructing the ASTs is a dicey process,
4603 // and this approach is far more likely to get the corner cases right.
4604 if (CurContext->isDependentContext())
4605 BaseInit = Init;
4606 }
4607
4608 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4609 BaseSpec->isVirtual(),
4610 InitRange.getBegin(),
4611 BaseInit.getAs<Expr>(),
4612 InitRange.getEnd(), EllipsisLoc);
4613}
4614
4615// Create a static_cast\<T&&>(expr).
4616static Expr *CastForMoving(Sema &SemaRef, Expr *E, QualType T = QualType()) {
4617 if (T.isNull()) T = E->getType();
4618 QualType TargetType = SemaRef.BuildReferenceType(
4619 T, /*SpelledAsLValue*/false, SourceLocation(), DeclarationName());
4620 SourceLocation ExprLoc = E->getBeginLoc();
4621 TypeSourceInfo *TargetLoc = SemaRef.Context.getTrivialTypeSourceInfo(
4622 TargetType, ExprLoc);
4623
4624 return SemaRef.BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E,
4625 SourceRange(ExprLoc, ExprLoc),
4626 E->getSourceRange()).get();
4627}
4628
4629/// ImplicitInitializerKind - How an implicit base or member initializer should
4630/// initialize its base or member.
4631enum ImplicitInitializerKind {
4632 IIK_Default,
4633 IIK_Copy,
4634 IIK_Move,
4635 IIK_Inherit
4636};
4637
4638static bool
4639BuildImplicitBaseInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4640 ImplicitInitializerKind ImplicitInitKind,
4641 CXXBaseSpecifier *BaseSpec,
4642 bool IsInheritedVirtualBase,
4643 CXXCtorInitializer *&CXXBaseInit) {
4644 InitializedEntity InitEntity
4645 = InitializedEntity::InitializeBase(SemaRef.Context, BaseSpec,
4646 IsInheritedVirtualBase);
4647
4648 ExprResult BaseInit;
4649
4650 switch (ImplicitInitKind) {
4651 case IIK_Inherit:
4652 case IIK_Default: {
4653 InitializationKind InitKind
4654 = InitializationKind::CreateDefault(Constructor->getLocation());
4655 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4656 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4657 break;
4658 }
4659
4660 case IIK_Move:
4661 case IIK_Copy: {
4662 bool Moving = ImplicitInitKind == IIK_Move;
4663 ParmVarDecl *Param = Constructor->getParamDecl(0);
4664 QualType ParamType = Param->getType().getNonReferenceType();
4665
4666 Expr *CopyCtorArg =
4667 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4668 SourceLocation(), Param, false,
4669 Constructor->getLocation(), ParamType,
4670 VK_LValue, nullptr);
4671
4672 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(CopyCtorArg));
4673
4674 // Cast to the base class to avoid ambiguities.
4675 QualType ArgTy =
4676 SemaRef.Context.getQualifiedType(BaseSpec->getType().getUnqualifiedType(),
4677 ParamType.getQualifiers());
4678
4679 if (Moving) {
4680 CopyCtorArg = CastForMoving(SemaRef, CopyCtorArg);
4681 }
4682
4683 CXXCastPath BasePath;
4684 BasePath.push_back(BaseSpec);
4685 CopyCtorArg = SemaRef.ImpCastExprToType(CopyCtorArg, ArgTy,
4686 CK_UncheckedDerivedToBase,
4687 Moving ? VK_XValue : VK_LValue,
4688 &BasePath).get();
4689
4690 InitializationKind InitKind
4691 = InitializationKind::CreateDirect(Constructor->getLocation(),
4692 SourceLocation(), SourceLocation());
4693 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, CopyCtorArg);
4694 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, CopyCtorArg);
4695 break;
4696 }
4697 }
4698
4699 BaseInit = SemaRef.MaybeCreateExprWithCleanups(BaseInit);
4700 if (BaseInit.isInvalid())
4701 return true;
4702
4703 CXXBaseInit =
4704 new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4705 SemaRef.Context.getTrivialTypeSourceInfo(BaseSpec->getType(),
4706 SourceLocation()),
4707 BaseSpec->isVirtual(),
4708 SourceLocation(),
4709 BaseInit.getAs<Expr>(),
4710 SourceLocation(),
4711 SourceLocation());
4712
4713 return false;
4714}
4715
4716static bool RefersToRValueRef(Expr *MemRef) {
4717 ValueDecl *Referenced = cast<MemberExpr>(MemRef)->getMemberDecl();
4718 return Referenced->getType()->isRValueReferenceType();
4719}
4720
4721static bool
4722BuildImplicitMemberInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4723 ImplicitInitializerKind ImplicitInitKind,
4724 FieldDecl *Field, IndirectFieldDecl *Indirect,
4725 CXXCtorInitializer *&CXXMemberInit) {
4726 if (Field->isInvalidDecl())
4727 return true;
4728
4729 SourceLocation Loc = Constructor->getLocation();
4730
4731 if (ImplicitInitKind == IIK_Copy || ImplicitInitKind == IIK_Move) {
4732 bool Moving = ImplicitInitKind == IIK_Move;
4733 ParmVarDecl *Param = Constructor->getParamDecl(0);
4734 QualType ParamType = Param->getType().getNonReferenceType();
4735
4736 // Suppress copying zero-width bitfields.
4737 if (Field->isZeroLengthBitField(SemaRef.Context))
4738 return false;
4739
4740 Expr *MemberExprBase =
4741 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4742 SourceLocation(), Param, false,
4743 Loc, ParamType, VK_LValue, nullptr);
4744
4745 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(MemberExprBase));
4746
4747 if (Moving) {
4748 MemberExprBase = CastForMoving(SemaRef, MemberExprBase);
4749 }
4750
4751 // Build a reference to this field within the parameter.
4752 CXXScopeSpec SS;
4753 LookupResult MemberLookup(SemaRef, Field->getDeclName(), Loc,
4754 Sema::LookupMemberName);
4755 MemberLookup.addDecl(Indirect ? cast<ValueDecl>(Indirect)
4756 : cast<ValueDecl>(Field), AS_public);
4757 MemberLookup.resolveKind();
4758 ExprResult CtorArg
4759 = SemaRef.BuildMemberReferenceExpr(MemberExprBase,
4760 ParamType, Loc,
4761 /*IsArrow=*/false,
4762 SS,
4763 /*TemplateKWLoc=*/SourceLocation(),
4764 /*FirstQualifierInScope=*/nullptr,
4765 MemberLookup,
4766 /*TemplateArgs=*/nullptr,
4767 /*S*/nullptr);
4768 if (CtorArg.isInvalid())
4769 return true;
4770
4771 // C++11 [class.copy]p15:
4772 // - if a member m has rvalue reference type T&&, it is direct-initialized
4773 // with static_cast<T&&>(x.m);
4774 if (RefersToRValueRef(CtorArg.get())) {
4775 CtorArg = CastForMoving(SemaRef, CtorArg.get());
4776 }
4777
4778 InitializedEntity Entity =
4779 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4780 /*Implicit*/ true)
4781 : InitializedEntity::InitializeMember(Field, nullptr,
4782 /*Implicit*/ true);
4783
4784 // Direct-initialize to use the copy constructor.
4785 InitializationKind InitKind =
4786 InitializationKind::CreateDirect(Loc, SourceLocation(), SourceLocation());
4787
4788 Expr *CtorArgE = CtorArg.getAs<Expr>();
4789 InitializationSequence InitSeq(SemaRef, Entity, InitKind, CtorArgE);
4790 ExprResult MemberInit =
4791 InitSeq.Perform(SemaRef, Entity, InitKind, MultiExprArg(&CtorArgE, 1));
4792 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4793 if (MemberInit.isInvalid())
4794 return true;
4795
4796 if (Indirect)
4797 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4798 SemaRef.Context, Indirect, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4799 else
4800 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4801 SemaRef.Context, Field, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4802 return false;
4803 }
4804
4805 assert((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) &&(static_cast<void> (0))
4806 "Unhandled implicit init kind!")(static_cast<void> (0));
4807
4808 QualType FieldBaseElementType =
4809 SemaRef.Context.getBaseElementType(Field->getType());
4810
4811 if (FieldBaseElementType->isRecordType()) {
4812 InitializedEntity InitEntity =
4813 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4814 /*Implicit*/ true)
4815 : InitializedEntity::InitializeMember(Field, nullptr,
4816 /*Implicit*/ true);
4817 InitializationKind InitKind =
4818 InitializationKind::CreateDefault(Loc);
4819
4820 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4821 ExprResult MemberInit =
4822 InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4823
4824 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4825 if (MemberInit.isInvalid())
4826 return true;
4827
4828 if (Indirect)
4829 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4830 Indirect, Loc,
4831 Loc,
4832 MemberInit.get(),
4833 Loc);
4834 else
4835 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4836 Field, Loc, Loc,
4837 MemberInit.get(),
4838 Loc);
4839 return false;
4840 }
4841
4842 if (!Field->getParent()->isUnion()) {
4843 if (FieldBaseElementType->isReferenceType()) {
4844 SemaRef.Diag(Constructor->getLocation(),
4845 diag::err_uninitialized_member_in_ctor)
4846 << (int)Constructor->isImplicit()
4847 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4848 << 0 << Field->getDeclName();
4849 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4850 return true;
4851 }
4852
4853 if (FieldBaseElementType.isConstQualified()) {
4854 SemaRef.Diag(Constructor->getLocation(),
4855 diag::err_uninitialized_member_in_ctor)
4856 << (int)Constructor->isImplicit()
4857 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4858 << 1 << Field->getDeclName();
4859 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4860 return true;
4861 }
4862 }
4863
4864 if (FieldBaseElementType.hasNonTrivialObjCLifetime()) {
4865 // ARC and Weak:
4866 // Default-initialize Objective-C pointers to NULL.
4867 CXXMemberInit
4868 = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
4869 Loc, Loc,
4870 new (SemaRef.Context) ImplicitValueInitExpr(Field->getType()),
4871 Loc);
4872 return false;
4873 }
4874
4875 // Nothing to initialize.
4876 CXXMemberInit = nullptr;
4877 return false;
4878}
4879
4880namespace {
4881struct BaseAndFieldInfo {
4882 Sema &S;
4883 CXXConstructorDecl *Ctor;
4884 bool AnyErrorsInInits;
4885 ImplicitInitializerKind IIK;
4886 llvm::DenseMap<const void *, CXXCtorInitializer*> AllBaseFields;
4887 SmallVector<CXXCtorInitializer*, 8> AllToInit;
4888 llvm::DenseMap<TagDecl*, FieldDecl*> ActiveUnionMember;
4889
4890 BaseAndFieldInfo(Sema &S, CXXConstructorDecl *Ctor, bool ErrorsInInits)
4891 : S(S), Ctor(Ctor), AnyErrorsInInits(ErrorsInInits) {
4892 bool Generated = Ctor->isImplicit() || Ctor->isDefaulted();
4893 if (Ctor->getInheritedConstructor())
4894 IIK = IIK_Inherit;
4895 else if (Generated && Ctor->isCopyConstructor())
4896 IIK = IIK_Copy;
4897 else if (Generated && Ctor->isMoveConstructor())
4898 IIK = IIK_Move;
4899 else
4900 IIK = IIK_Default;
4901 }
4902
4903 bool isImplicitCopyOrMove() const {
4904 switch (IIK) {
4905 case IIK_Copy:
4906 case IIK_Move:
4907 return true;
4908
4909 case IIK_Default:
4910 case IIK_Inherit:
4911 return false;
4912 }
4913
4914 llvm_unreachable("Invalid ImplicitInitializerKind!")__builtin_unreachable();
4915 }
4916
4917 bool addFieldInitializer(CXXCtorInitializer *Init) {
4918 AllToInit.push_back(Init);
4919
4920 // Check whether this initializer makes the field "used".
4921 if (Init->getInit()->HasSideEffects(S.Context))
4922 S.UnusedPrivateFields.remove(Init->getAnyMember());
4923
4924 return false;
4925 }
4926
4927 bool isInactiveUnionMember(FieldDecl *Field) {
4928 RecordDecl *Record = Field->getParent();
4929 if (!Record->isUnion())
4930 return false;
4931
4932 if (FieldDecl *Active =
4933 ActiveUnionMember.lookup(Record->getCanonicalDecl()))
4934 return Active != Field->getCanonicalDecl();
4935
4936 // In an implicit copy or move constructor, ignore any in-class initializer.
4937 if (isImplicitCopyOrMove())
4938 return true;
4939
4940 // If there's no explicit initialization, the field is active only if it
4941 // has an in-class initializer...
4942 if (Field->hasInClassInitializer())
4943 return false;
4944 // ... or it's an anonymous struct or union whose class has an in-class
4945 // initializer.
4946 if (!Field->isAnonymousStructOrUnion())
4947 return true;
4948 CXXRecordDecl *FieldRD = Field->getType()->getAsCXXRecordDecl();
4949 return !FieldRD->hasInClassInitializer();
4950 }
4951
4952 /// Determine whether the given field is, or is within, a union member
4953 /// that is inactive (because there was an initializer given for a different
4954 /// member of the union, or because the union was not initialized at all).
4955 bool isWithinInactiveUnionMember(FieldDecl *Field,
4956 IndirectFieldDecl *Indirect) {
4957 if (!Indirect)
4958 return isInactiveUnionMember(Field);
4959
4960 for (auto *C : Indirect->chain()) {
4961 FieldDecl *Field = dyn_cast<FieldDecl>(C);
4962 if (Field && isInactiveUnionMember(Field))
4963 return true;
4964 }
4965 return false;
4966 }
4967};
4968}
4969
4970/// Determine whether the given type is an incomplete or zero-lenfgth
4971/// array type.
4972static bool isIncompleteOrZeroLengthArrayType(ASTContext &Context, QualType T) {
4973 if (T->isIncompleteArrayType())
4974 return true;
4975
4976 while (const ConstantArrayType *ArrayT = Context.getAsConstantArrayType(T)) {
4977 if (!ArrayT->getSize())
4978 return true;
4979
4980 T = ArrayT->getElementType();
4981 }
4982
4983 return false;
4984}
4985
4986static bool CollectFieldInitializer(Sema &SemaRef, BaseAndFieldInfo &Info,
4987 FieldDecl *Field,
4988 IndirectFieldDecl *Indirect = nullptr) {
4989 if (Field->isInvalidDecl())
19
Assuming the condition is false
20
Taking false branch
4990 return false;
4991
4992 // Overwhelmingly common case: we have a direct initializer for this field.
4993 if (CXXCtorInitializer *Init =
21
Assuming 'Init' is null
22
Taking false branch
4994 Info.AllBaseFields.lookup(Field->getCanonicalDecl()))
4995 return Info.addFieldInitializer(Init);
4996
4997 // C++11 [class.base.init]p8:
4998 // if the entity is a non-static data member that has a
4999 // brace-or-equal-initializer and either
5000 // -- the constructor's class is a union and no other variant member of that
5001 // union is designated by a mem-initializer-id or
5002 // -- the constructor's class is not a union, and, if the entity is a member
5003 // of an anonymous union, no other member of that union is designated by
5004 // a mem-initializer-id,
5005 // the entity is initialized as specified in [dcl.init].
5006 //
5007 // We also apply the same rules to handle anonymous structs within anonymous
5008 // unions.
5009 if (Info.isWithinInactiveUnionMember(Field, Indirect))
5010 return false;
5011
5012 if (Field->hasInClassInitializer() && !Info.isImplicitCopyOrMove()) {
23
Taking true branch
5013 ExprResult DIE =
5014 SemaRef.BuildCXXDefaultInitExpr(Info.Ctor->getLocation(), Field);
24
Calling 'Sema::BuildCXXDefaultInitExpr'
5015 if (DIE.isInvalid())
5016 return true;
5017
5018 auto Entity = InitializedEntity::InitializeMember(Field, nullptr, true);
5019 SemaRef.checkInitializerLifetime(Entity, DIE.get());
5020
5021 CXXCtorInitializer *Init;
5022 if (Indirect)
5023 Init = new (SemaRef.Context)
5024 CXXCtorInitializer(SemaRef.Context, Indirect, SourceLocation(),
5025 SourceLocation(), DIE.get(), SourceLocation());
5026 else
5027 Init = new (SemaRef.Context)
5028 CXXCtorInitializer(SemaRef.Context, Field, SourceLocation(),
5029 SourceLocation(), DIE.get(), SourceLocation());
5030 return Info.addFieldInitializer(Init);
5031 }
5032
5033 // Don't initialize incomplete or zero-length arrays.
5034 if (isIncompleteOrZeroLengthArrayType(SemaRef.Context, Field->getType()))
5035 return false;
5036
5037 // Don't try to build an implicit initializer if there were semantic
5038 // errors in any of the initializers (and therefore we might be
5039 // missing some that the user actually wrote).
5040 if (Info.AnyErrorsInInits)
5041 return false;
5042
5043 CXXCtorInitializer *Init = nullptr;
5044 if (BuildImplicitMemberInitializer(Info.S, Info.Ctor, Info.IIK, Field,
5045 Indirect, Init))
5046 return true;
5047
5048 if (!Init)
5049 return false;
5050
5051 return Info.addFieldInitializer(Init);
5052}
5053
5054bool
5055Sema::SetDelegatingInitializer(CXXConstructorDecl *Constructor,
5056 CXXCtorInitializer *Initializer) {
5057 assert(Initializer->isDelegatingInitializer())(static_cast<void> (0));
5058 Constructor->setNumCtorInitializers(1);
5059 CXXCtorInitializer **initializer =
5060 new (Context) CXXCtorInitializer*[1];
5061 memcpy(initializer, &Initializer, sizeof (CXXCtorInitializer*));
5062 Constructor->setCtorInitializers(initializer);
5063
5064 if (CXXDestructorDecl *Dtor = LookupDestructor(Constructor->getParent())) {
5065 MarkFunctionReferenced(Initializer->getSourceLocation(), Dtor);
5066 DiagnoseUseOfDecl(Dtor, Initializer->getSourceLocation());
5067 }
5068
5069 DelegatingCtorDecls.push_back(Constructor);
5070
5071 DiagnoseUninitializedFields(*this, Constructor);
5072
5073 return false;
5074}
5075
5076bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
5077 ArrayRef<CXXCtorInitializer *> Initializers) {
5078 if (Constructor->isDependentContext()) {
6
Assuming the condition is false
7
Taking false branch
5079 // Just store the initializers as written, they will be checked during
5080 // instantiation.
5081 if (!Initializers.empty()) {
5082 Constructor->setNumCtorInitializers(Initializers.size());
5083 CXXCtorInitializer **baseOrMemberInitializers =
5084 new (Context) CXXCtorInitializer*[Initializers.size()];
5085 memcpy(baseOrMemberInitializers, Initializers.data(),
5086 Initializers.size() * sizeof(CXXCtorInitializer*));
5087 Constructor->setCtorInitializers(baseOrMemberInitializers);
5088 }
5089
5090 // Let template instantiation know whether we had errors.
5091 if (AnyErrors)
5092 Constructor->setInvalidDecl();
5093
5094 return false;
5095 }
5096
5097 BaseAndFieldInfo Info(*this, Constructor, AnyErrors);
5098
5099 // We need to build the initializer AST according to order of construction
5100 // and not what user specified in the Initializers list.
5101 CXXRecordDecl *ClassDecl = Constructor->getParent()->getDefinition();
5102 if (!ClassDecl)
8
Assuming 'ClassDecl' is non-null
9
Taking false branch
5103 return true;
5104
5105 bool HadError = false;
5106
5107 for (unsigned i = 0; i < Initializers.size(); i++) {
10
Assuming the condition is false
11
Loop condition is false. Execution continues on line 5131
5108 CXXCtorInitializer *Member = Initializers[i];
5109
5110 if (Member->isBaseInitializer())
5111 Info.AllBaseFields[Member->getBaseClass()->getAs<RecordType>()] = Member;
5112 else {
5113 Info.AllBaseFields[Member->getAnyMember()->getCanonicalDecl()] = Member;
5114
5115 if (IndirectFieldDecl *F = Member->getIndirectMember()) {
5116 for (auto *C : F->chain()) {
5117 FieldDecl *FD = dyn_cast<FieldDecl>(C);
5118 if (FD && FD->getParent()->isUnion())
5119 Info.ActiveUnionMember.insert(std::make_pair(
5120 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
5121 }
5122 } else if (FieldDecl *FD = Member->getMember()) {
5123 if (FD->getParent()->isUnion())
5124 Info.ActiveUnionMember.insert(std::make_pair(
5125 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
5126 }
5127 }
5128 }
5129
5130 // Keep track of the direct virtual bases.
5131 llvm::SmallPtrSet<CXXBaseSpecifier *, 16> DirectVBases;
5132 for (auto &I : ClassDecl->bases()) {
12
Assuming '__begin1' is equal to '__end1'
5133 if (I.isVirtual())
5134 DirectVBases.insert(&I);
5135 }
5136
5137 // Push virtual bases before others.
5138 for (auto &VBase : ClassDecl->vbases()) {
13
Assuming '__begin1' is equal to '__end1'
5139 if (CXXCtorInitializer *Value
5140 = Info.AllBaseFields.lookup(VBase.getType()->getAs<RecordType>())) {
5141 // [class.base.init]p7, per DR257:
5142 // A mem-initializer where the mem-initializer-id names a virtual base
5143 // class is ignored during execution of a constructor of any class that
5144 // is not the most derived class.
5145 if (ClassDecl->isAbstract()) {
5146 // FIXME: Provide a fixit to remove the base specifier. This requires
5147 // tracking the location of the associated comma for a base specifier.
5148 Diag(Value->getSourceLocation(), diag::warn_abstract_vbase_init_ignored)
5149 << VBase.getType() << ClassDecl;
5150 DiagnoseAbstractType(ClassDecl);
5151 }
5152
5153 Info.AllToInit.push_back(Value);
5154 } else if (!AnyErrors && !ClassDecl->isAbstract()) {
5155 // [class.base.init]p8, per DR257:
5156 // If a given [...] base class is not named by a mem-initializer-id
5157 // [...] and the entity is not a virtual base class of an abstract
5158 // class, then [...] the entity is default-initialized.
5159 bool IsInheritedVirtualBase = !DirectVBases.count(&VBase);
5160 CXXCtorInitializer *CXXBaseInit;
5161 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
5162 &VBase, IsInheritedVirtualBase,
5163 CXXBaseInit)) {
5164 HadError = true;
5165 continue;
5166 }
5167
5168 Info.AllToInit.push_back(CXXBaseInit);
5169 }
5170 }
5171
5172 // Non-virtual bases.
5173 for (auto &Base : ClassDecl->bases()) {
14
Assuming '__begin1' is equal to '__end1'
5174 // Virtuals are in the virtual base list and already constructed.
5175 if (Base.isVirtual())
5176 continue;
5177
5178 if (CXXCtorInitializer *Value
5179 = Info.AllBaseFields.lookup(Base.getType()->getAs<RecordType>())) {
5180 Info.AllToInit.push_back(Value);
5181 } else if (!AnyErrors) {
5182 CXXCtorInitializer *CXXBaseInit;
5183 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
5184 &Base, /*IsInheritedVirtualBase=*/false,
5185 CXXBaseInit)) {
5186 HadError = true;
5187 continue;
5188 }
5189
5190 Info.AllToInit.push_back(CXXBaseInit);
5191 }
5192 }
5193
5194 // Fields.
5195 for (auto *Mem : ClassDecl->decls()) {
5196 if (auto *F
15.1
'F' is non-null
15.1
'F' is non-null
15.1
'F' is non-null
= dyn_cast<FieldDecl>(Mem)) {
15
Assuming 'Mem' is a 'FieldDecl'
16
Taking true branch
5197 // C++ [class.bit]p2:
5198 // A declaration for a bit-field that omits the identifier declares an
5199 // unnamed bit-field. Unnamed bit-fields are not members and cannot be
5200 // initialized.
5201 if (F->isUnnamedBitfield())
5202 continue;
5203
5204 // If we're not generating the implicit copy/move constructor, then we'll
5205 // handle anonymous struct/union fields based on their individual
5206 // indirect fields.
5207 if (F->isAnonymousStructOrUnion() && !Info.isImplicitCopyOrMove())
17
Assuming the condition is false
5208 continue;
5209
5210 if (CollectFieldInitializer(*this, Info, F))
18
Calling 'CollectFieldInitializer'
5211 HadError = true;
5212 continue;
5213 }
5214
5215 // Beyond this point, we only consider default initialization.
5216 if (Info.isImplicitCopyOrMove())
5217 continue;
5218
5219 if (auto *F = dyn_cast<IndirectFieldDecl>(Mem)) {
5220 if (F->getType()->isIncompleteArrayType()) {
5221 assert(ClassDecl->hasFlexibleArrayMember() &&(static_cast<void> (0))
5222 "Incomplete array type is not valid")(static_cast<void> (0));
5223 continue;
5224 }
5225
5226 // Initialize each field of an anonymous struct individually.
5227 if (CollectFieldInitializer(*this, Info, F->getAnonField(), F))
5228 HadError = true;
5229
5230 continue;
5231 }
5232 }
5233
5234 unsigned NumInitializers = Info.AllToInit.size();
5235 if (NumInitializers > 0) {
5236 Constructor->setNumCtorInitializers(NumInitializers);
5237 CXXCtorInitializer **baseOrMemberInitializers =
5238 new (Context) CXXCtorInitializer*[NumInitializers];
5239 memcpy(baseOrMemberInitializers, Info.AllToInit.data(),
5240 NumInitializers * sizeof(CXXCtorInitializer*));
5241 Constructor->setCtorInitializers(baseOrMemberInitializers);
5242
5243 // Constructors implicitly reference the base and member
5244 // destructors.
5245 MarkBaseAndMemberDestructorsReferenced(Constructor->getLocation(),
5246 Constructor->getParent());
5247 }
5248
5249 return HadError;
5250}
5251
5252static void PopulateKeysForFields(FieldDecl *Field, SmallVectorImpl<const void*> &IdealInits) {
5253 if (const RecordType *RT = Field->getType()->getAs<RecordType>()) {
5254 const RecordDecl *RD = RT->getDecl();
5255 if (RD->isAnonymousStructOrUnion()) {
5256 for (auto *Field : RD->fields())
5257 PopulateKeysForFields(Field, IdealInits);
5258 return;
5259 }
5260 }
5261 IdealInits.push_back(Field->getCanonicalDecl());
5262}
5263
5264static const void *GetKeyForBase(ASTContext &Context, QualType BaseType) {
5265 return Context.getCanonicalType(BaseType).getTypePtr();
5266}
5267
5268static const void *GetKeyForMember(ASTContext &Context,
5269 CXXCtorInitializer *Member) {
5270 if (!Member->isAnyMemberInitializer())
5271 return GetKeyForBase(Context, QualType(Member->getBaseClass(), 0));
5272
5273 return Member->getAnyMember()->getCanonicalDecl();
5274}
5275
5276static void AddInitializerToDiag(const Sema::SemaDiagnosticBuilder &Diag,
5277 const CXXCtorInitializer *Previous,
5278 const CXXCtorInitializer *Current) {
5279 if (Previous->isAnyMemberInitializer())
5280 Diag << 0 << Previous->getAnyMember();
5281 else
5282 Diag << 1 << Previous->getTypeSourceInfo()->getType();
5283
5284 if (Current->isAnyMemberInitializer())
5285 Diag << 0 << Current->getAnyMember();
5286 else
5287 Diag << 1 << Current->getTypeSourceInfo()->getType();
5288}
5289
5290static void DiagnoseBaseOrMemInitializerOrder(
5291 Sema &SemaRef, const CXXConstructorDecl *Constructor,
5292 ArrayRef<CXXCtorInitializer *> Inits) {
5293 if (Constructor->getDeclContext()->isDependentContext())
5294 return;
5295
5296 // Don't check initializers order unless the warning is enabled at the
5297 // location of at least one initializer.
5298 bool ShouldCheckOrder = false;
5299 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
5300 CXXCtorInitializer *Init = Inits[InitIndex];
5301 if (!SemaRef.Diags.isIgnored(diag::warn_initializer_out_of_order,
5302 Init->getSourceLocation())) {
5303 ShouldCheckOrder = true;
5304 break;
5305 }
5306 }
5307 if (!ShouldCheckOrder)
5308 return;
5309
5310 // Build the list of bases and members in the order that they'll
5311 // actually be initialized. The explicit initializers should be in
5312 // this same order but may be missing things.
5313 SmallVector<const void*, 32> IdealInitKeys;
5314
5315 const CXXRecordDecl *ClassDecl = Constructor->getParent();
5316
5317 // 1. Virtual bases.
5318 for (const auto &VBase : ClassDecl->vbases())
5319 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, VBase.getType()));
5320
5321 // 2. Non-virtual bases.
5322 for (const auto &Base : ClassDecl->bases()) {
5323 if (Base.isVirtual())
5324 continue;
5325 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, Base.getType()));
5326 }
5327
5328 // 3. Direct fields.
5329 for (auto *Field : ClassDecl->fields()) {
5330 if (Field->isUnnamedBitfield())
5331 continue;
5332
5333 PopulateKeysForFields(Field, IdealInitKeys);
5334 }
5335
5336 unsigned NumIdealInits = IdealInitKeys.size();
5337 unsigned IdealIndex = 0;
5338
5339 // Track initializers that are in an incorrect order for either a warning or
5340 // note if multiple ones occur.
5341 SmallVector<unsigned> WarnIndexes;
5342 // Correlates the index of an initializer in the init-list to the index of
5343 // the field/base in the class.
5344 SmallVector<std::pair<unsigned, unsigned>, 32> CorrelatedInitOrder;
5345
5346 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
5347 const void *InitKey = GetKeyForMember(SemaRef.Context, Inits[InitIndex]);
5348
5349 // Scan forward to try to find this initializer in the idealized
5350 // initializers list.
5351 for (; IdealIndex != NumIdealInits; ++IdealIndex)
5352 if (InitKey == IdealInitKeys[IdealIndex])
5353 break;
5354
5355 // If we didn't find this initializer, it must be because we
5356 // scanned past it on a previous iteration. That can only
5357 // happen if we're out of order; emit a warning.
5358 if (IdealIndex == NumIdealInits && InitIndex) {
5359 WarnIndexes.push_back(InitIndex);
5360
5361 // Move back to the initializer's location in the ideal list.
5362 for (IdealIndex = 0; IdealIndex != NumIdealInits; ++IdealIndex)
5363 if (InitKey == IdealInitKeys[IdealIndex])
5364 break;
5365
5366 assert(IdealIndex < NumIdealInits &&(static_cast<void> (0))
5367 "initializer not found in initializer list")(static_cast<void> (0));
5368 }
5369 CorrelatedInitOrder.emplace_back(IdealIndex, InitIndex);
5370 }
5371
5372 if (WarnIndexes.empty())
5373 return;
5374
5375 // Sort based on the ideal order, first in the pair.
5376 llvm::sort(CorrelatedInitOrder,
5377 [](auto &LHS, auto &RHS) { return LHS.first < RHS.first; });
5378
5379 // Introduce a new scope as SemaDiagnosticBuilder needs to be destroyed to
5380 // emit the diagnostic before we can try adding notes.
5381 {
5382 Sema::SemaDiagnosticBuilder D = SemaRef.Diag(
5383 Inits[WarnIndexes.front() - 1]->getSourceLocation(),
5384 WarnIndexes.size() == 1 ? diag::warn_initializer_out_of_order
5385 : diag::warn_some_initializers_out_of_order);
5386
5387 for (unsigned I = 0; I < CorrelatedInitOrder.size(); ++I) {
5388 if (CorrelatedInitOrder[I].second == I)
5389 continue;
5390 // Ideally we would be using InsertFromRange here, but clang doesn't
5391 // appear to handle InsertFromRange correctly when the source range is
5392 // modified by another fix-it.
5393 D << FixItHint::CreateReplacement(
5394 Inits[I]->getSourceRange(),
5395 Lexer::getSourceText(
5396 CharSourceRange::getTokenRange(
5397 Inits[CorrelatedInitOrder[I].second]->getSourceRange()),
5398 SemaRef.getSourceManager(), SemaRef.getLangOpts()));
5399 }
5400
5401 // If there is only 1 item out of order, the warning expects the name and
5402 // type of each being added to it.
5403 if (WarnIndexes.size() == 1) {
5404 AddInitializerToDiag(D, Inits[WarnIndexes.front() - 1],
5405 Inits[WarnIndexes.front()]);
5406 return;
5407 }
5408 }
5409 // More than 1 item to warn, create notes letting the user know which ones
5410 // are bad.
5411 for (unsigned WarnIndex : WarnIndexes) {
5412 const clang::CXXCtorInitializer *PrevInit = Inits[WarnIndex - 1];
5413 auto D = SemaRef.Diag(PrevInit->getSourceLocation(),
5414 diag::note_initializer_out_of_order);
5415 AddInitializerToDiag(D, PrevInit, Inits[WarnIndex]);
5416 D << PrevInit->getSourceRange();
5417 }
5418}
5419
5420namespace {
5421bool CheckRedundantInit(Sema &S,
5422 CXXCtorInitializer *Init,
5423 CXXCtorInitializer *&PrevInit) {
5424 if (!PrevInit) {
5425 PrevInit = Init;
5426 return false;
5427 }
5428
5429 if (FieldDecl *Field = Init->getAnyMember())
5430 S.Diag(Init->getSourceLocation(),
5431 diag::err_multiple_mem_initialization)
5432 << Field->getDeclName()
5433 << Init->getSourceRange();
5434 else {
5435 const Type *BaseClass = Init->getBaseClass();
5436 assert(BaseClass && "neither field nor base")(static_cast<void> (0));
5437 S.Diag(Init->getSourceLocation(),
5438 diag::err_multiple_base_initialization)
5439 << QualType(BaseClass, 0)
5440 << Init->getSourceRange();
5441 }
5442 S.Diag(PrevInit->getSourceLocation(), diag::note_previous_initializer)
5443 << 0 << PrevInit->getSourceRange();
5444
5445 return true;
5446}
5447
5448typedef std::pair<NamedDecl *, CXXCtorInitializer *> UnionEntry;
5449typedef llvm::DenseMap<RecordDecl*, UnionEntry> RedundantUnionMap;
5450
5451bool CheckRedundantUnionInit(Sema &S,
5452 CXXCtorInitializer *Init,
5453 RedundantUnionMap &Unions) {
5454 FieldDecl *Field = Init->getAnyMember();
5455 RecordDecl *Parent = Field->getParent();
5456 NamedDecl *Child = Field;
5457
5458 while (Parent->isAnonymousStructOrUnion() || Parent->isUnion()) {
5459 if (Parent->isUnion()) {
5460 UnionEntry &En = Unions[Parent];
5461 if (En.first && En.first != Child) {
5462 S.Diag(Init->getSourceLocation(),
5463 diag::err_multiple_mem_union_initialization)
5464 << Field->getDeclName()
5465 << Init->getSourceRange();
5466 S.Diag(En.second->getSourceLocation(), diag::note_previous_initializer)
5467 << 0 << En.second->getSourceRange();
5468 return true;
5469 }
5470 if (!En.first) {
5471 En.first = Child;
5472 En.second = Init;
5473 }
5474 if (!Parent->isAnonymousStructOrUnion())
5475 return false;
5476 }
5477
5478 Child = Parent;
5479 Parent = cast<RecordDecl>(Parent->getDeclContext());
5480 }
5481
5482 return false;
5483}
5484} // namespace
5485
5486/// ActOnMemInitializers - Handle the member initializers for a constructor.
5487void Sema::ActOnMemInitializers(Decl *ConstructorDecl,
5488 SourceLocation ColonLoc,
5489 ArrayRef<CXXCtorInitializer*> MemInits,
5490 bool AnyErrors) {
5491 if (!ConstructorDecl)
5492 return;
5493
5494 AdjustDeclIfTemplate(ConstructorDecl);
5495
5496 CXXConstructorDecl *Constructor
5497 = dyn_cast<CXXConstructorDecl>(ConstructorDecl);
5498
5499 if (!Constructor) {
5500 Diag(ColonLoc, diag::err_only_constructors_take_base_inits);
5501 return;
5502 }
5503
5504 // Mapping for the duplicate initializers check.
5505 // For member initializers, this is keyed with a FieldDecl*.
5506 // For base initializers, this is keyed with a Type*.
5507 llvm::DenseMap<const void *, CXXCtorInitializer *> Members;
5508
5509 // Mapping for the inconsistent anonymous-union initializers check.
5510 RedundantUnionMap MemberUnions;
5511
5512 bool HadError = false;
5513 for (unsigned i = 0; i < MemInits.size(); i++) {
5514 CXXCtorInitializer *Init = MemInits[i];
5515
5516 // Set the source order index.
5517 Init->setSourceOrder(i);
5518
5519 if (Init->isAnyMemberInitializer()) {
5520 const void *Key = GetKeyForMember(Context, Init);
5521 if (CheckRedundantInit(*this, Init, Members[Key]) ||
5522 CheckRedundantUnionInit(*this, Init, MemberUnions))
5523 HadError = true;
5524 } else if (Init->isBaseInitializer()) {
5525 const void *Key = GetKeyForMember(Context, Init);
5526 if (CheckRedundantInit(*this, Init, Members[Key]))
5527 HadError = true;
5528 } else {
5529 assert(Init->isDelegatingInitializer())(static_cast<void> (0));
5530 // This must be the only initializer
5531 if (MemInits.size() != 1) {
5532 Diag(Init->getSourceLocation(),
5533 diag::err_delegating_initializer_alone)
5534 << Init->getSourceRange() << MemInits[i ? 0 : 1]->getSourceRange();
5535 // We will treat this as being the only initializer.
5536 }
5537 SetDelegatingInitializer(Constructor, MemInits[i]);
5538 // Return immediately as the initializer is set.
5539 return;
5540 }
5541 }
5542
5543 if (HadError)
5544 return;
5545
5546 DiagnoseBaseOrMemInitializerOrder(*this, Constructor, MemInits);
5547
5548 SetCtorInitializers(Constructor, AnyErrors, MemInits);
5549
5550 DiagnoseUninitializedFields(*this, Constructor);
5551}
5552
5553void
5554Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
5555 CXXRecordDecl *ClassDecl) {
5556 // Ignore dependent contexts. Also ignore unions, since their members never
5557 // have destructors implicitly called.
5558 if (ClassDecl->isDependentContext() || ClassDecl->isUnion())
5559 return;
5560
5561 // FIXME: all the access-control diagnostics are positioned on the
5562 // field/base declaration. That's probably good; that said, the
5563 // user might reasonably want to know why the destructor is being
5564 // emitted, and we currently don't say.
5565
5566 // Non-static data members.
5567 for (auto *Field : ClassDecl->fields()) {
5568 if (Field->isInvalidDecl())
5569 continue;
5570
5571 // Don't destroy incomplete or zero-length arrays.
5572 if (isIncompleteOrZeroLengthArrayType(Context, Field->getType()))
5573 continue;
5574
5575 QualType FieldType = Context.getBaseElementType(Field->getType());
5576
5577 const RecordType* RT = FieldType->getAs<RecordType>();
5578 if (!RT)
5579 continue;
5580
5581 CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5582 if (FieldClassDecl->isInvalidDecl())
5583 continue;
5584 if (FieldClassDecl->hasIrrelevantDestructor())
5585 continue;
5586 // The destructor for an implicit anonymous union member is never invoked.
5587 if (FieldClassDecl->isUnion() && FieldClassDecl->isAnonymousStructOrUnion())
5588 continue;
5589
5590 CXXDestructorDecl *Dtor = LookupDestructor(FieldClassDecl);
5591 assert(Dtor && "No dtor found for FieldClassDecl!")(static_cast<void> (0));
5592 CheckDestructorAccess(Field->getLocation(), Dtor,
5593 PDiag(diag::err_access_dtor_field)
5594 << Field->getDeclName()
5595 << FieldType);
5596
5597 MarkFunctionReferenced(Location, Dtor);
5598 DiagnoseUseOfDecl(Dtor, Location);
5599 }
5600
5601 // We only potentially invoke the destructors of potentially constructed
5602 // subobjects.
5603 bool VisitVirtualBases = !ClassDecl->isAbstract();
5604
5605 // If the destructor exists and has already been marked used in the MS ABI,
5606 // then virtual base destructors have already been checked and marked used.
5607 // Skip checking them again to avoid duplicate diagnostics.
5608 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
5609 CXXDestructorDecl *Dtor = ClassDecl->getDestructor();
5610 if (Dtor && Dtor->isUsed())
5611 VisitVirtualBases = false;
5612 }
5613
5614 llvm::SmallPtrSet<const RecordType *, 8> DirectVirtualBases;
5615
5616 // Bases.
5617 for (const auto &Base : ClassDecl->bases()) {
5618 const RecordType *RT = Base.getType()->getAs<RecordType>();
5619 if (!RT)
5620 continue;
5621
5622 // Remember direct virtual bases.
5623 if (Base.isVirtual()) {
5624 if (!VisitVirtualBases)
5625 continue;
5626 DirectVirtualBases.insert(RT);
5627 }
5628
5629 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5630 // If our base class is invalid, we probably can't get its dtor anyway.
5631 if (BaseClassDecl->isInvalidDecl())
5632 continue;
5633 if (BaseClassDecl->hasIrrelevantDestructor())
5634 continue;
5635
5636 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5637 assert(Dtor && "No dtor found for BaseClassDecl!")(static_cast<void> (0));
5638
5639 // FIXME: caret should be on the start of the class name
5640 CheckDestructorAccess(Base.getBeginLoc(), Dtor,
5641 PDiag(diag::err_access_dtor_base)
5642 << Base.getType() << Base.getSourceRange(),
5643 Context.getTypeDeclType(ClassDecl));
5644
5645 MarkFunctionReferenced(Location, Dtor);
5646 DiagnoseUseOfDecl(Dtor, Location);
5647 }
5648
5649 if (VisitVirtualBases)
5650 MarkVirtualBaseDestructorsReferenced(Location, ClassDecl,
5651 &DirectVirtualBases);
5652}
5653
5654void Sema::MarkVirtualBaseDestructorsReferenced(
5655 SourceLocation Location, CXXRecordDecl *ClassDecl,
5656 llvm::SmallPtrSetImpl<const RecordType *> *DirectVirtualBases) {
5657 // Virtual bases.
5658 for (const auto &VBase : ClassDecl->vbases()) {
5659 // Bases are always records in a well-formed non-dependent class.
5660 const RecordType *RT = VBase.getType()->castAs<RecordType>();
5661
5662 // Ignore already visited direct virtual bases.
5663 if (DirectVirtualBases && DirectVirtualBases->count(RT))
5664 continue;
5665
5666 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5667 // If our base class is invalid, we probably can't get its dtor anyway.
5668 if (BaseClassDecl->isInvalidDecl())
5669 continue;
5670 if (BaseClassDecl->hasIrrelevantDestructor())
5671 continue;
5672
5673 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5674 assert(Dtor && "No dtor found for BaseClassDecl!")(static_cast<void> (0));
5675 if (CheckDestructorAccess(
5676 ClassDecl->getLocation(), Dtor,
5677 PDiag(diag::err_access_dtor_vbase)
5678 << Context.getTypeDeclType(ClassDecl) << VBase.getType(),
5679 Context.getTypeDeclType(ClassDecl)) ==
5680 AR_accessible) {
5681 CheckDerivedToBaseConversion(
5682 Context.getTypeDeclType(ClassDecl), VBase.getType(),
5683 diag::err_access_dtor_vbase, 0, ClassDecl->getLocation(),
5684 SourceRange(), DeclarationName(), nullptr);
5685 }
5686
5687 MarkFunctionReferenced(Location, Dtor);
5688 DiagnoseUseOfDecl(Dtor, Location);
5689 }
5690}
5691
5692void Sema::ActOnDefaultCtorInitializers(Decl *CDtorDecl) {
5693 if (!CDtorDecl)
1
Assuming 'CDtorDecl' is non-null
2
Taking false branch
5694 return;
5695
5696 if (CXXConstructorDecl *Constructor
3.1
'Constructor' is non-null
3.1
'Constructor' is non-null
3.1
'Constructor' is non-null
4
Taking true branch
5697 = dyn_cast<CXXConstructorDecl>(CDtorDecl)) {
3
Assuming 'CDtorDecl' is a 'CXXConstructorDecl'
5698 SetCtorInitializers(Constructor, /*AnyErrors=*/false);
5
Calling 'Sema::SetCtorInitializers'
5699 DiagnoseUninitializedFields(*this, Constructor); 5700 } 5701} 5702 5703bool Sema::isAbstractType(SourceLocation Loc, QualType T) { 5704 if (!getLangOpts().CPlusPlus) 5705 return false; 5706 5707 const auto *RD = Context.getBaseElementType(T)->getAsCXXRecordDecl(); 5708 if (!RD) 5709 return false; 5710 5711 // FIXME: Per [temp.inst]p1, we are supposed to trigger instantiation of a 5712 // class template specialization here, but doing so breaks a lot of code. 5713 5714 // We can't answer whether something is abstract until it has a 5715 // definition. If it's currently being defined, we'll walk back 5716 // over all the declarations when we have a full definition. 5717 const CXXRecordDecl *Def = RD->getDefinition(); 5718 if (!Def || Def->isBeingDefined()) 5719 return false; 5720 5721 return RD->isAbstract(); 5722} 5723 5724bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T, 5725 TypeDiagnoser &Diagnoser) { 5726 if (!isAbstractType(Loc, T)) 5727 return false; 5728 5729 T = Context.getBaseElementType(T); 5730 Diagnoser.diagnose(*this, Loc, T); 5731 DiagnoseAbstractType(T->getAsCXXRecordDecl()); 5732 return true; 5733} 5734 5735void Sema::DiagnoseAbstractType(const CXXRecordDecl *RD) { 5736 // Check if we've already emitted the list of pure virtual functions 5737 // for this class. 5738 if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD)) 5739 return; 5740 5741 // If the diagnostic is suppressed, don't emit the notes. We're only 5742 // going to emit them once, so try to attach them to a diagnostic we're 5743 // actually going to show. 5744 if (Diags.isLastDiagnosticIgnored()) 5745 return; 5746 5747 CXXFinalOverriderMap FinalOverriders; 5748 RD->getFinalOverriders(FinalOverriders); 5749 5750 // Keep a set of seen pure methods so we won't diagnose the same method 5751 // more than once. 5752 llvm::SmallPtrSet<const CXXMethodDecl *, 8> SeenPureMethods; 5753 5754 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 5755 MEnd = FinalOverriders.end(); 5756 M != MEnd; 5757 ++M) { 5758 for (OverridingMethods::iterator SO = M->second.begin(), 5759 SOEnd = M->second.end(); 5760 SO != SOEnd; ++SO) { 5761 // C++ [class.abstract]p4: 5762 // A class is abstract if it contains or inherits at least one 5763 // pure virtual function for which the final overrider is pure 5764 // virtual. 5765 5766 // 5767 if (SO->second.size() != 1) 5768 continue; 5769 5770 if (!SO->second.front().Method->isPure()) 5771 continue; 5772 5773 if (!SeenPureMethods.insert(SO->second.front().Method).second) 5774 continue; 5775 5776 Diag(SO->second.front().Method->getLocation(), 5777 diag::note_pure_virtual_function) 5778 << SO->second.front().Method->getDeclName() << RD->getDeclName(); 5779 } 5780 } 5781 5782 if (!PureVirtualClassDiagSet) 5783 PureVirtualClassDiagSet.reset(new RecordDeclSetTy); 5784 PureVirtualClassDiagSet->insert(RD); 5785} 5786 5787namespace { 5788struct AbstractUsageInfo { 5789 Sema &S; 5790 CXXRecordDecl *Record; 5791 CanQualType AbstractType; 5792 bool Invalid; 5793 5794 AbstractUsageInfo(Sema &S, CXXRecordDecl *Record) 5795 : S(S), Record(Record), 5796 AbstractType(S.Context.getCanonicalType( 5797 S.Context.getTypeDeclType(Record))), 5798 Invalid(false) {} 5799 5800 void DiagnoseAbstractType() { 5801 if (Invalid) return; 5802 S.DiagnoseAbstractType(Record); 5803 Invalid = true; 5804 } 5805 5806 void CheckType(const NamedDecl *D, TypeLoc TL, Sema::AbstractDiagSelID Sel); 5807}; 5808 5809struct CheckAbstractUsage { 5810 AbstractUsageInfo &Info; 5811 const NamedDecl *Ctx; 5812 5813 CheckAbstractUsage(AbstractUsageInfo &Info, const NamedDecl *Ctx) 5814 : Info(Info), Ctx(Ctx) {} 5815 5816 void Visit(TypeLoc TL, Sema::AbstractDiagSelID Sel) { 5817 switch (TL.getTypeLocClass()) { 5818#define ABSTRACT_TYPELOC(CLASS, PARENT) 5819#define TYPELOC(CLASS, PARENT) \ 5820 case TypeLoc::CLASS: Check(TL.castAs<CLASS##TypeLoc>(), Sel); break; 5821#include "clang/AST/TypeLocNodes.def" 5822 } 5823 } 5824 5825 void Check(FunctionProtoTypeLoc TL, Sema::AbstractDiagSelID Sel) { 5826 Visit(TL.getReturnLoc(), Sema::AbstractReturnType); 5827 for (unsigned I = 0, E = TL.getNumParams(); I != E; ++I) { 5828 if (!TL.getParam(I)) 5829 continue; 5830 5831 TypeSourceInfo *TSI = TL.getParam(I)->getTypeSourceInfo(); 5832 if (TSI) Visit(TSI->getTypeLoc(), Sema::AbstractParamType); 5833 } 5834 } 5835 5836 void Check(ArrayTypeLoc TL, Sema::AbstractDiagSelID Sel) { 5837 Visit(TL.getElementLoc(), Sema::AbstractArrayType); 5838 } 5839 5840 void Check(TemplateSpecializationTypeLoc TL, Sema::AbstractDiagSelID Sel) { 5841 // Visit the type parameters from a permissive context. 5842 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) { 5843 TemplateArgumentLoc TAL = TL.getArgLoc(I); 5844 if (TAL.getArgument().getKind() == TemplateArgument::Type) 5845 if (TypeSourceInfo *TSI = TAL.getTypeSourceInfo()) 5846 Visit(TSI->getTypeLoc(), Sema::AbstractNone); 5847 // TODO: other template argument types? 5848 } 5849 } 5850 5851 // Visit pointee types from a permissive context. 5852#define CheckPolymorphic(Type)void Check(Type TL, Sema::AbstractDiagSelID Sel) { Visit(TL.getNextTypeLoc
(), Sema::AbstractNone); }
\
5853 void Check(Type TL, Sema::AbstractDiagSelID Sel) { \ 5854 Visit(TL.getNextTypeLoc(), Sema::AbstractNone); \ 5855 } 5856 CheckPolymorphic(PointerTypeLoc)void Check(PointerTypeLoc TL, Sema::AbstractDiagSelID Sel) { Visit
(TL.getNextTypeLoc(), Sema::AbstractNone); }
5857 CheckPolymorphic(ReferenceTypeLoc)void Check(ReferenceTypeLoc TL, Sema::AbstractDiagSelID Sel) {
Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5858 CheckPolymorphic(MemberPointerTypeLoc)void Check(MemberPointerTypeLoc TL, Sema::AbstractDiagSelID Sel
) { Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5859 CheckPolymorphic(BlockPointerTypeLoc)void Check(BlockPointerTypeLoc TL, Sema::AbstractDiagSelID Sel
) { Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5860 CheckPolymorphic(AtomicTypeLoc)void Check(AtomicTypeLoc TL, Sema::AbstractDiagSelID Sel) { Visit
(TL.getNextTypeLoc(), Sema::AbstractNone); }
5861 5862 /// Handle all the types we haven't given a more specific 5863 /// implementation for above. 5864 void Check(TypeLoc TL, Sema::AbstractDiagSelID Sel) { 5865 // Every other kind of type that we haven't called out already 5866 // that has an inner type is either (1) sugar or (2) contains that 5867 // inner type in some way as a subobject. 5868 if (TypeLoc Next = TL.getNextTypeLoc()) 5869 return Visit(Next, Sel); 5870 5871 // If there's no inner type and we're in a permissive context, 5872 // don't diagnose. 5873 if (Sel == Sema::AbstractNone) return; 5874 5875 // Check whether the type matches the abstract type. 5876 QualType T = TL.getType(); 5877 if (T->isArrayType()) { 5878 Sel = Sema::AbstractArrayType; 5879 T = Info.S.Context.getBaseElementType(T); 5880 } 5881 CanQualType CT = T->getCanonicalTypeUnqualified().getUnqualifiedType(); 5882 if (CT != Info.AbstractType) return; 5883 5884 // It matched; do some magic. 5885 if (Sel == Sema::AbstractArrayType) { 5886 Info.S.Diag(Ctx->getLocation(), diag::err_array_of_abstract_type) 5887 << T << TL.getSourceRange(); 5888 } else { 5889 Info.S.Diag(Ctx->getLocation(), diag::err_abstract_type_in_decl) 5890 << Sel << T << TL.getSourceRange(); 5891 } 5892 Info.DiagnoseAbstractType(); 5893 } 5894}; 5895 5896void AbstractUsageInfo::CheckType(const NamedDecl *D, TypeLoc TL, 5897 Sema::AbstractDiagSelID Sel) { 5898 CheckAbstractUsage(*this, D).Visit(TL, Sel); 5899} 5900 5901} 5902 5903/// Check for invalid uses of an abstract type in a method declaration. 5904static void CheckAbstractClassUsage(AbstractUsageInfo &Info, 5905 CXXMethodDecl *MD) { 5906 // No need to do the check on definitions, which require that 5907 // the return/param types be complete. 5908 if (MD->doesThisDeclarationHaveABody()) 5909 return; 5910 5911 // For safety's sake, just ignore it if we don't have type source 5912 // information. This should never happen for non-implicit methods, 5913 // but... 5914 if (TypeSourceInfo *TSI = MD->getTypeSourceInfo()) 5915 Info.CheckType(MD, TSI->getTypeLoc(), Sema::AbstractNone); 5916} 5917 5918/// Check for invalid uses of an abstract type within a class definition. 5919static void CheckAbstractClassUsage(AbstractUsageInfo &Info, 5920 CXXRecordDecl *RD) { 5921 for (auto *D : RD->decls()) { 5922 if (D->isImplicit()) continue; 5923 5924 // Methods and method templates. 5925 if (isa<CXXMethodDecl>(D)) { 5926 CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(D)); 5927 } else if (isa<FunctionTemplateDecl>(D)) { 5928 FunctionDecl *FD = cast<FunctionTemplateDecl>(D)->getTemplatedDecl(); 5929 CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(FD)); 5930 5931 // Fields and static variables. 5932 } else if (isa<FieldDecl>(D)) { 5933 FieldDecl *FD = cast<FieldDecl>(D); 5934 if (TypeSourceInfo *TSI = FD->getTypeSourceInfo()) 5935 Info.CheckType(FD, TSI->getTypeLoc(), Sema::AbstractFieldType); 5936 } else if (isa<VarDecl>(D)) { 5937 VarDecl *VD = cast<VarDecl>(D); 5938 if (TypeSourceInfo *TSI = VD->getTypeSourceInfo()) 5939 Info.CheckType(VD, TSI->getTypeLoc(), Sema::AbstractVariableType); 5940 5941 // Nested classes and class templates. 5942 } else if (isa<CXXRecordDecl>(D)) { 5943 CheckAbstractClassUsage(Info, cast<CXXRecordDecl>(D)); 5944 } else if (isa<ClassTemplateDecl>(D)) { 5945 CheckAbstractClassUsage(Info, 5946 cast<ClassTemplateDecl>(D)->getTemplatedDecl()); 5947 } 5948 } 5949} 5950 5951static void ReferenceDllExportedMembers(Sema &S, CXXRecordDecl *Class) { 5952 Attr *ClassAttr = getDLLAttr(Class); 5953 if (!ClassAttr) 5954 return; 5955 5956 assert(ClassAttr->getKind() == attr::DLLExport)(static_cast<void> (0)); 5957 5958 TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind(); 5959 5960 if (TSK == TSK_ExplicitInstantiationDeclaration) 5961 // Don't go any further if this is just an explicit instantiation 5962 // declaration. 5963 return; 5964 5965 // Add a context note to explain how we got to any diagnostics produced below. 5966 struct MarkingClassDllexported { 5967 Sema &S; 5968 MarkingClassDllexported(Sema &S, CXXRecordDecl *Class, 5969 SourceLocation AttrLoc) 5970 : S(S) { 5971 Sema::CodeSynthesisContext Ctx; 5972 Ctx.Kind = Sema::CodeSynthesisContext::MarkingClassDllexported; 5973 Ctx.PointOfInstantiation = AttrLoc; 5974 Ctx.Entity = Class; 5975 S.pushCodeSynthesisContext(Ctx); 5976 } 5977 ~MarkingClassDllexported() { 5978 S.popCodeSynthesisContext(); 5979 } 5980 } MarkingDllexportedContext(S, Class, ClassAttr->getLocation()); 5981 5982 if (S.Context.getTargetInfo().getTriple().isWindowsGNUEnvironment()) 5983 S.MarkVTableUsed(Class->getLocation(), Class, true); 5984 5985 for (Decl *Member : Class->decls()) { 5986 // Skip members that were not marked exported. 5987 if (!Member->hasAttr<DLLExportAttr>()) 5988 continue; 5989 5990 // Defined static variables that are members of an exported base 5991 // class must be marked export too. 5992 auto *VD = dyn_cast<VarDecl>(Member); 5993 if (VD && VD->getStorageClass() == SC_Static && 5994 TSK == TSK_ImplicitInstantiation) 5995 S.MarkVariableReferenced(VD->getLocation(), VD); 5996 5997 auto *MD = dyn_cast<CXXMethodDecl>(Member); 5998 if (!MD) 5999 continue; 6000 6001 if (MD->isUserProvided()) { 6002 // Instantiate non-default class member functions ... 6003 6004 // .. except for certain kinds of template specializations. 6005 if (TSK == TSK_ImplicitInstantiation && !ClassAttr->isInherited()) 6006 continue; 6007 6008 // If this is an MS ABI dllexport default constructor, instantiate any 6009 // default arguments. 6010 if (S.Context.getTargetInfo().getCXXABI().isMicrosoft()) { 6011 auto *CD = dyn_cast<CXXConstructorDecl>(MD); 6012 if (CD && CD->isDefaultConstructor() && TSK == TSK_Undeclared) { 6013 S.InstantiateDefaultCtorDefaultArgs(CD); 6014 } 6015 } 6016 6017 S.MarkFunctionReferenced(Class->getLocation(), MD); 6018 6019 // The function will be passed to the consumer when its definition is 6020 // encountered. 6021 } else if (MD->isExplicitlyDefaulted()) { 6022 // Synthesize and instantiate explicitly defaulted methods. 6023 S.MarkFunctionReferenced(Class->getLocation(), MD); 6024 6025 if (TSK != TSK_ExplicitInstantiationDefinition) { 6026 // Except for explicit instantiation defs, we will not see the 6027 // definition again later, so pass it to the consumer now. 6028 S.Consumer.HandleTopLevelDecl(DeclGroupRef(MD)); 6029 } 6030 } else if (!MD->isTrivial() || 6031 MD->isCopyAssignmentOperator() || 6032 MD->isMoveAssignmentOperator()) { 6033 // Synthesize and instantiate non-trivial implicit methods, and the copy 6034 // and move assignment operators. The latter are exported even if they 6035 // are trivial, because the address of an operator can be taken and 6036 // should compare equal across libraries. 6037 S.MarkFunctionReferenced(Class->getLocation(), MD); 6038 6039 // There is no later point when we will see the definition of this 6040 // function, so pass it to the consumer now. 6041 S.Consumer.HandleTopLevelDecl(DeclGroupRef(MD)); 6042 }