Bug Summary

File:clang/lib/Sema/SemaDeclCXX.cpp
Warning:line 3912, column 5
Called C++ object pointer is null

Annotated Source Code

Press '?' to see keyboard shortcuts

clang -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 -mthread-model posix -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -dwarf-column-info -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-11/lib/clang/11.0.0 -D CLANG_VENDOR="Debian " -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema -I /build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/include -I /build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/build-llvm/include -I /build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-11/lib/clang/11.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fno-common -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2020-03-09-184146-41876-1 -x c++ /build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/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/STLExtras.h"
42#include "llvm/ADT/SmallString.h"
43#include "llvm/ADT/StringExtras.h"
44#include <map>
45#include <set>
46
47using namespace clang;
48
49//===----------------------------------------------------------------------===//
50// CheckDefaultArgumentVisitor
51//===----------------------------------------------------------------------===//
52
53namespace {
54 /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses
55 /// the default argument of a parameter to determine whether it
56 /// contains any ill-formed subexpressions. For example, this will
57 /// diagnose the use of local variables or parameters within the
58 /// default argument expression.
59 class CheckDefaultArgumentVisitor
60 : public StmtVisitor<CheckDefaultArgumentVisitor, bool> {
61 Expr *DefaultArg;
62 Sema *S;
63
64 public:
65 CheckDefaultArgumentVisitor(Expr *defarg, Sema *s)
66 : DefaultArg(defarg), S(s) {}
67
68 bool VisitExpr(Expr *Node);
69 bool VisitDeclRefExpr(DeclRefExpr *DRE);
70 bool VisitCXXThisExpr(CXXThisExpr *ThisE);
71 bool VisitLambdaExpr(LambdaExpr *Lambda);
72 bool VisitPseudoObjectExpr(PseudoObjectExpr *POE);
73 };
74
75 /// VisitExpr - Visit all of the children of this expression.
76 bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) {
77 bool IsInvalid = false;
78 for (Stmt *SubStmt : Node->children())
79 IsInvalid |= Visit(SubStmt);
80 return IsInvalid;
81 }
82
83 /// VisitDeclRefExpr - Visit a reference to a declaration, to
84 /// determine whether this declaration can be used in the default
85 /// argument expression.
86 bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) {
87 NamedDecl *Decl = DRE->getDecl();
88 if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) {
89 // C++ [dcl.fct.default]p9
90 // Default arguments are evaluated each time the function is
91 // called. The order of evaluation of function arguments is
92 // unspecified. Consequently, parameters of a function shall not
93 // be used in default argument expressions, even if they are not
94 // evaluated. Parameters of a function declared before a default
95 // argument expression are in scope and can hide namespace and
96 // class member names.
97 return S->Diag(DRE->getBeginLoc(),
98 diag::err_param_default_argument_references_param)
99 << Param->getDeclName() << DefaultArg->getSourceRange();
100 } else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) {
101 // C++ [dcl.fct.default]p7
102 // Local variables shall not be used in default argument
103 // expressions.
104 if (VDecl->isLocalVarDecl())
105 return S->Diag(DRE->getBeginLoc(),
106 diag::err_param_default_argument_references_local)
107 << VDecl->getDeclName() << DefaultArg->getSourceRange();
108 }
109
110 return false;
111 }
112
113 /// VisitCXXThisExpr - Visit a C++ "this" expression.
114 bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(CXXThisExpr *ThisE) {
115 // C++ [dcl.fct.default]p8:
116 // The keyword this shall not be used in a default argument of a
117 // member function.
118 return S->Diag(ThisE->getBeginLoc(),
119 diag::err_param_default_argument_references_this)
120 << ThisE->getSourceRange();
121 }
122
123 bool CheckDefaultArgumentVisitor::VisitPseudoObjectExpr(PseudoObjectExpr *POE) {
124 bool Invalid = false;
125 for (PseudoObjectExpr::semantics_iterator
126 i = POE->semantics_begin(), e = POE->semantics_end(); i != e; ++i) {
127 Expr *E = *i;
128
129 // Look through bindings.
130 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
131 E = OVE->getSourceExpr();
132 assert(E && "pseudo-object binding without source expression?")((E && "pseudo-object binding without source expression?"
) ? static_cast<void> (0) : __assert_fail ("E && \"pseudo-object binding without source expression?\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 132, __PRETTY_FUNCTION__))
;
133 }
134
135 Invalid |= Visit(E);
136 }
137 return Invalid;
138 }
139
140 bool CheckDefaultArgumentVisitor::VisitLambdaExpr(LambdaExpr *Lambda) {
141 // C++11 [expr.lambda.prim]p13:
142 // A lambda-expression appearing in a default argument shall not
143 // implicitly or explicitly capture any entity.
144 if (Lambda->capture_begin() == Lambda->capture_end())
145 return false;
146
147 return S->Diag(Lambda->getBeginLoc(), diag::err_lambda_capture_default_arg);
148 }
149}
150
151void
152Sema::ImplicitExceptionSpecification::CalledDecl(SourceLocation CallLoc,
153 const CXXMethodDecl *Method) {
154 // If we have an MSAny spec already, don't bother.
155 if (!Method || ComputedEST == EST_MSAny)
156 return;
157
158 const FunctionProtoType *Proto
159 = Method->getType()->getAs<FunctionProtoType>();
160 Proto = Self->ResolveExceptionSpec(CallLoc, Proto);
161 if (!Proto)
162 return;
163
164 ExceptionSpecificationType EST = Proto->getExceptionSpecType();
165
166 // If we have a throw-all spec at this point, ignore the function.
167 if (ComputedEST == EST_None)
168 return;
169
170 if (EST == EST_None && Method->hasAttr<NoThrowAttr>())
171 EST = EST_BasicNoexcept;
172
173 switch (EST) {
174 case EST_Unparsed:
175 case EST_Uninstantiated:
176 case EST_Unevaluated:
177 llvm_unreachable("should not see unresolved exception specs here")::llvm::llvm_unreachable_internal("should not see unresolved exception specs here"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 177)
;
178
179 // If this function can throw any exceptions, make a note of that.
180 case EST_MSAny:
181 case EST_None:
182 // FIXME: Whichever we see last of MSAny and None determines our result.
183 // We should make a consistent, order-independent choice here.
184 ClearExceptions();
185 ComputedEST = EST;
186 return;
187 case EST_NoexceptFalse:
188 ClearExceptions();
189 ComputedEST = EST_None;
190 return;
191 // FIXME: If the call to this decl is using any of its default arguments, we
192 // need to search them for potentially-throwing calls.
193 // If this function has a basic noexcept, it doesn't affect the outcome.
194 case EST_BasicNoexcept:
195 case EST_NoexceptTrue:
196 case EST_NoThrow:
197 return;
198 // If we're still at noexcept(true) and there's a throw() callee,
199 // change to that specification.
200 case EST_DynamicNone:
201 if (ComputedEST == EST_BasicNoexcept)
202 ComputedEST = EST_DynamicNone;
203 return;
204 case EST_DependentNoexcept:
205 llvm_unreachable(::llvm::llvm_unreachable_internal("should not generate implicit declarations for dependent cases"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 206)
206 "should not generate implicit declarations for dependent cases")::llvm::llvm_unreachable_internal("should not generate implicit declarations for dependent cases"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 206)
;
207 case EST_Dynamic:
208 break;
209 }
210 assert(EST == EST_Dynamic && "EST case not considered earlier.")((EST == EST_Dynamic && "EST case not considered earlier."
) ? static_cast<void> (0) : __assert_fail ("EST == EST_Dynamic && \"EST case not considered earlier.\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 210, __PRETTY_FUNCTION__))
;
211 assert(ComputedEST != EST_None &&((ComputedEST != EST_None && "Shouldn't collect exceptions when throw-all is guaranteed."
) ? static_cast<void> (0) : __assert_fail ("ComputedEST != EST_None && \"Shouldn't collect exceptions when throw-all is guaranteed.\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 212, __PRETTY_FUNCTION__))
212 "Shouldn't collect exceptions when throw-all is guaranteed.")((ComputedEST != EST_None && "Shouldn't collect exceptions when throw-all is guaranteed."
) ? static_cast<void> (0) : __assert_fail ("ComputedEST != EST_None && \"Shouldn't collect exceptions when throw-all is guaranteed.\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 212, __PRETTY_FUNCTION__))
;
213 ComputedEST = EST_Dynamic;
214 // Record the exceptions in this function's exception specification.
215 for (const auto &E : Proto->exceptions())
216 if (ExceptionsSeen.insert(Self->Context.getCanonicalType(E)).second)
217 Exceptions.push_back(E);
218}
219
220void Sema::ImplicitExceptionSpecification::CalledStmt(Stmt *S) {
221 if (!S || ComputedEST == EST_MSAny)
222 return;
223
224 // FIXME:
225 //
226 // C++0x [except.spec]p14:
227 // [An] implicit exception-specification specifies the type-id T if and
228 // only if T is allowed by the exception-specification of a function directly
229 // invoked by f's implicit definition; f shall allow all exceptions if any
230 // function it directly invokes allows all exceptions, and f shall allow no
231 // exceptions if every function it directly invokes allows no exceptions.
232 //
233 // Note in particular that if an implicit exception-specification is generated
234 // for a function containing a throw-expression, that specification can still
235 // be noexcept(true).
236 //
237 // Note also that 'directly invoked' is not defined in the standard, and there
238 // is no indication that we should only consider potentially-evaluated calls.
239 //
240 // Ultimately we should implement the intent of the standard: the exception
241 // specification should be the set of exceptions which can be thrown by the
242 // implicit definition. For now, we assume that any non-nothrow expression can
243 // throw any exception.
244
245 if (Self->canThrow(S))
246 ComputedEST = EST_None;
247}
248
249bool
250Sema::SetParamDefaultArgument(ParmVarDecl *Param, Expr *Arg,
251 SourceLocation EqualLoc) {
252 if (RequireCompleteType(Param->getLocation(), Param->getType(),
253 diag::err_typecheck_decl_incomplete_type)) {
254 Param->setInvalidDecl();
255 return true;
256 }
257
258 // C++ [dcl.fct.default]p5
259 // A default argument expression is implicitly converted (clause
260 // 4) to the parameter type. The default argument expression has
261 // the same semantic constraints as the initializer expression in
262 // a declaration of a variable of the parameter type, using the
263 // copy-initialization semantics (8.5).
264 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
265 Param);
266 InitializationKind Kind = InitializationKind::CreateCopy(Param->getLocation(),
267 EqualLoc);
268 InitializationSequence InitSeq(*this, Entity, Kind, Arg);
269 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Arg);
270 if (Result.isInvalid())
271 return true;
272 Arg = Result.getAs<Expr>();
273
274 CheckCompletedExpr(Arg, EqualLoc);
275 Arg = MaybeCreateExprWithCleanups(Arg);
276
277 // Okay: add the default argument to the parameter
278 Param->setDefaultArg(Arg);
279
280 // We have already instantiated this parameter; provide each of the
281 // instantiations with the uninstantiated default argument.
282 UnparsedDefaultArgInstantiationsMap::iterator InstPos
283 = UnparsedDefaultArgInstantiations.find(Param);
284 if (InstPos != UnparsedDefaultArgInstantiations.end()) {
285 for (unsigned I = 0, N = InstPos->second.size(); I != N; ++I)
286 InstPos->second[I]->setUninstantiatedDefaultArg(Arg);
287
288 // We're done tracking this parameter's instantiations.
289 UnparsedDefaultArgInstantiations.erase(InstPos);
290 }
291
292 return false;
293}
294
295/// ActOnParamDefaultArgument - Check whether the default argument
296/// provided for a function parameter is well-formed. If so, attach it
297/// to the parameter declaration.
298void
299Sema::ActOnParamDefaultArgument(Decl *param, SourceLocation EqualLoc,
300 Expr *DefaultArg) {
301 if (!param || !DefaultArg)
302 return;
303
304 ParmVarDecl *Param = cast<ParmVarDecl>(param);
305 UnparsedDefaultArgLocs.erase(Param);
306
307 // Default arguments are only permitted in C++
308 if (!getLangOpts().CPlusPlus) {
309 Diag(EqualLoc, diag::err_param_default_argument)
310 << DefaultArg->getSourceRange();
311 Param->setInvalidDecl();
312 return;
313 }
314
315 // Check for unexpanded parameter packs.
316 if (DiagnoseUnexpandedParameterPack(DefaultArg, UPPC_DefaultArgument)) {
317 Param->setInvalidDecl();
318 return;
319 }
320
321 // C++11 [dcl.fct.default]p3
322 // A default argument expression [...] shall not be specified for a
323 // parameter pack.
324 if (Param->isParameterPack()) {
325 Diag(EqualLoc, diag::err_param_default_argument_on_parameter_pack)
326 << DefaultArg->getSourceRange();
327 return;
328 }
329
330 // Check that the default argument is well-formed
331 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg, this);
332 if (DefaultArgChecker.Visit(DefaultArg)) {
333 Param->setInvalidDecl();
334 return;
335 }
336
337 SetParamDefaultArgument(Param, DefaultArg, EqualLoc);
338}
339
340/// ActOnParamUnparsedDefaultArgument - We've seen a default
341/// argument for a function parameter, but we can't parse it yet
342/// because we're inside a class definition. Note that this default
343/// argument will be parsed later.
344void Sema::ActOnParamUnparsedDefaultArgument(Decl *param,
345 SourceLocation EqualLoc,
346 SourceLocation ArgLoc) {
347 if (!param)
348 return;
349
350 ParmVarDecl *Param = cast<ParmVarDecl>(param);
351 Param->setUnparsedDefaultArg();
352 UnparsedDefaultArgLocs[Param] = ArgLoc;
353}
354
355/// ActOnParamDefaultArgumentError - Parsing or semantic analysis of
356/// the default argument for the parameter param failed.
357void Sema::ActOnParamDefaultArgumentError(Decl *param,
358 SourceLocation EqualLoc) {
359 if (!param)
360 return;
361
362 ParmVarDecl *Param = cast<ParmVarDecl>(param);
363 Param->setInvalidDecl();
364 UnparsedDefaultArgLocs.erase(Param);
365 Param->setDefaultArg(new(Context)
366 OpaqueValueExpr(EqualLoc,
367 Param->getType().getNonReferenceType(),
368 VK_RValue));
369}
370
371/// CheckExtraCXXDefaultArguments - Check for any extra default
372/// arguments in the declarator, which is not a function declaration
373/// or definition and therefore is not permitted to have default
374/// arguments. This routine should be invoked for every declarator
375/// that is not a function declaration or definition.
376void Sema::CheckExtraCXXDefaultArguments(Declarator &D) {
377 // C++ [dcl.fct.default]p3
378 // A default argument expression shall be specified only in the
379 // parameter-declaration-clause of a function declaration or in a
380 // template-parameter (14.1). It shall not be specified for a
381 // parameter pack. If it is specified in a
382 // parameter-declaration-clause, it shall not occur within a
383 // declarator or abstract-declarator of a parameter-declaration.
384 bool MightBeFunction = D.isFunctionDeclarationContext();
385 for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
386 DeclaratorChunk &chunk = D.getTypeObject(i);
387 if (chunk.Kind == DeclaratorChunk::Function) {
388 if (MightBeFunction) {
389 // This is a function declaration. It can have default arguments, but
390 // keep looking in case its return type is a function type with default
391 // arguments.
392 MightBeFunction = false;
393 continue;
394 }
395 for (unsigned argIdx = 0, e = chunk.Fun.NumParams; argIdx != e;
396 ++argIdx) {
397 ParmVarDecl *Param = cast<ParmVarDecl>(chunk.Fun.Params[argIdx].Param);
398 if (Param->hasUnparsedDefaultArg()) {
399 std::unique_ptr<CachedTokens> Toks =
400 std::move(chunk.Fun.Params[argIdx].DefaultArgTokens);
401 SourceRange SR;
402 if (Toks->size() > 1)
403 SR = SourceRange((*Toks)[1].getLocation(),
404 Toks->back().getLocation());
405 else
406 SR = UnparsedDefaultArgLocs[Param];
407 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
408 << SR;
409 } else if (Param->getDefaultArg()) {
410 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
411 << Param->getDefaultArg()->getSourceRange();
412 Param->setDefaultArg(nullptr);
413 }
414 }
415 } else if (chunk.Kind != DeclaratorChunk::Paren) {
416 MightBeFunction = false;
417 }
418 }
419}
420
421static bool functionDeclHasDefaultArgument(const FunctionDecl *FD) {
422 for (unsigned NumParams = FD->getNumParams(); NumParams > 0; --NumParams) {
423 const ParmVarDecl *PVD = FD->getParamDecl(NumParams-1);
424 if (!PVD->hasDefaultArg())
425 return false;
426 if (!PVD->hasInheritedDefaultArg())
427 return true;
428 }
429 return false;
430}
431
432/// MergeCXXFunctionDecl - Merge two declarations of the same C++
433/// function, once we already know that they have the same
434/// type. Subroutine of MergeFunctionDecl. Returns true if there was an
435/// error, false otherwise.
436bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old,
437 Scope *S) {
438 bool Invalid = false;
439
440 // The declaration context corresponding to the scope is the semantic
441 // parent, unless this is a local function declaration, in which case
442 // it is that surrounding function.
443 DeclContext *ScopeDC = New->isLocalExternDecl()
444 ? New->getLexicalDeclContext()
445 : New->getDeclContext();
446
447 // Find the previous declaration for the purpose of default arguments.
448 FunctionDecl *PrevForDefaultArgs = Old;
449 for (/**/; PrevForDefaultArgs;
450 // Don't bother looking back past the latest decl if this is a local
451 // extern declaration; nothing else could work.
452 PrevForDefaultArgs = New->isLocalExternDecl()
453 ? nullptr
454 : PrevForDefaultArgs->getPreviousDecl()) {
455 // Ignore hidden declarations.
456 if (!LookupResult::isVisible(*this, PrevForDefaultArgs))
457 continue;
458
459 if (S && !isDeclInScope(PrevForDefaultArgs, ScopeDC, S) &&
460 !New->isCXXClassMember()) {
461 // Ignore default arguments of old decl if they are not in
462 // the same scope and this is not an out-of-line definition of
463 // a member function.
464 continue;
465 }
466
467 if (PrevForDefaultArgs->isLocalExternDecl() != New->isLocalExternDecl()) {
468 // If only one of these is a local function declaration, then they are
469 // declared in different scopes, even though isDeclInScope may think
470 // they're in the same scope. (If both are local, the scope check is
471 // sufficient, and if neither is local, then they are in the same scope.)
472 continue;
473 }
474
475 // We found the right previous declaration.
476 break;
477 }
478
479 // C++ [dcl.fct.default]p4:
480 // For non-template functions, default arguments can be added in
481 // later declarations of a function in the same
482 // scope. Declarations in different scopes have completely
483 // distinct sets of default arguments. That is, declarations in
484 // inner scopes do not acquire default arguments from
485 // declarations in outer scopes, and vice versa. In a given
486 // function declaration, all parameters subsequent to a
487 // parameter with a default argument shall have default
488 // arguments supplied in this or previous declarations. A
489 // default argument shall not be redefined by a later
490 // declaration (not even to the same value).
491 //
492 // C++ [dcl.fct.default]p6:
493 // Except for member functions of class templates, the default arguments
494 // in a member function definition that appears outside of the class
495 // definition are added to the set of default arguments provided by the
496 // member function declaration in the class definition.
497 for (unsigned p = 0, NumParams = PrevForDefaultArgs
498 ? PrevForDefaultArgs->getNumParams()
499 : 0;
500 p < NumParams; ++p) {
501 ParmVarDecl *OldParam = PrevForDefaultArgs->getParamDecl(p);
502 ParmVarDecl *NewParam = New->getParamDecl(p);
503
504 bool OldParamHasDfl = OldParam ? OldParam->hasDefaultArg() : false;
505 bool NewParamHasDfl = NewParam->hasDefaultArg();
506
507 if (OldParamHasDfl && NewParamHasDfl) {
508 unsigned DiagDefaultParamID =
509 diag::err_param_default_argument_redefinition;
510
511 // MSVC accepts that default parameters be redefined for member functions
512 // of template class. The new default parameter's value is ignored.
513 Invalid = true;
514 if (getLangOpts().MicrosoftExt) {
515 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(New);
516 if (MD && MD->getParent()->getDescribedClassTemplate()) {
517 // Merge the old default argument into the new parameter.
518 NewParam->setHasInheritedDefaultArg();
519 if (OldParam->hasUninstantiatedDefaultArg())
520 NewParam->setUninstantiatedDefaultArg(
521 OldParam->getUninstantiatedDefaultArg());
522 else
523 NewParam->setDefaultArg(OldParam->getInit());
524 DiagDefaultParamID = diag::ext_param_default_argument_redefinition;
525 Invalid = false;
526 }
527 }
528
529 // FIXME: If we knew where the '=' was, we could easily provide a fix-it
530 // hint here. Alternatively, we could walk the type-source information
531 // for NewParam to find the last source location in the type... but it
532 // isn't worth the effort right now. This is the kind of test case that
533 // is hard to get right:
534 // int f(int);
535 // void g(int (*fp)(int) = f);
536 // void g(int (*fp)(int) = &f);
537 Diag(NewParam->getLocation(), DiagDefaultParamID)
538 << NewParam->getDefaultArgRange();
539
540 // Look for the function declaration where the default argument was
541 // actually written, which may be a declaration prior to Old.
542 for (auto Older = PrevForDefaultArgs;
543 OldParam->hasInheritedDefaultArg(); /**/) {
544 Older = Older->getPreviousDecl();
545 OldParam = Older->getParamDecl(p);
546 }
547
548 Diag(OldParam->getLocation(), diag::note_previous_definition)
549 << OldParam->getDefaultArgRange();
550 } else if (OldParamHasDfl) {
551 // Merge the old default argument into the new parameter unless the new
552 // function is a friend declaration in a template class. In the latter
553 // case the default arguments will be inherited when the friend
554 // declaration will be instantiated.
555 if (New->getFriendObjectKind() == Decl::FOK_None ||
556 !New->getLexicalDeclContext()->isDependentContext()) {
557 // It's important to use getInit() here; getDefaultArg()
558 // strips off any top-level ExprWithCleanups.
559 NewParam->setHasInheritedDefaultArg();
560 if (OldParam->hasUnparsedDefaultArg())
561 NewParam->setUnparsedDefaultArg();
562 else if (OldParam->hasUninstantiatedDefaultArg())
563 NewParam->setUninstantiatedDefaultArg(
564 OldParam->getUninstantiatedDefaultArg());
565 else
566 NewParam->setDefaultArg(OldParam->getInit());
567 }
568 } else if (NewParamHasDfl) {
569 if (New->getDescribedFunctionTemplate()) {
570 // Paragraph 4, quoted above, only applies to non-template functions.
571 Diag(NewParam->getLocation(),
572 diag::err_param_default_argument_template_redecl)
573 << NewParam->getDefaultArgRange();
574 Diag(PrevForDefaultArgs->getLocation(),
575 diag::note_template_prev_declaration)
576 << false;
577 } else if (New->getTemplateSpecializationKind()
578 != TSK_ImplicitInstantiation &&
579 New->getTemplateSpecializationKind() != TSK_Undeclared) {
580 // C++ [temp.expr.spec]p21:
581 // Default function arguments shall not be specified in a declaration
582 // or a definition for one of the following explicit specializations:
583 // - the explicit specialization of a function template;
584 // - the explicit specialization of a member function template;
585 // - the explicit specialization of a member function of a class
586 // template where the class template specialization to which the
587 // member function specialization belongs is implicitly
588 // instantiated.
589 Diag(NewParam->getLocation(), diag::err_template_spec_default_arg)
590 << (New->getTemplateSpecializationKind() ==TSK_ExplicitSpecialization)
591 << New->getDeclName()
592 << NewParam->getDefaultArgRange();
593 } else if (New->getDeclContext()->isDependentContext()) {
594 // C++ [dcl.fct.default]p6 (DR217):
595 // Default arguments for a member function of a class template shall
596 // be specified on the initial declaration of the member function
597 // within the class template.
598 //
599 // Reading the tea leaves a bit in DR217 and its reference to DR205
600 // leads me to the conclusion that one cannot add default function
601 // arguments for an out-of-line definition of a member function of a
602 // dependent type.
603 int WhichKind = 2;
604 if (CXXRecordDecl *Record
605 = dyn_cast<CXXRecordDecl>(New->getDeclContext())) {
606 if (Record->getDescribedClassTemplate())
607 WhichKind = 0;
608 else if (isa<ClassTemplatePartialSpecializationDecl>(Record))
609 WhichKind = 1;
610 else
611 WhichKind = 2;
612 }
613
614 Diag(NewParam->getLocation(),
615 diag::err_param_default_argument_member_template_redecl)
616 << WhichKind
617 << NewParam->getDefaultArgRange();
618 }
619 }
620 }
621
622 // DR1344: If a default argument is added outside a class definition and that
623 // default argument makes the function a special member function, the program
624 // is ill-formed. This can only happen for constructors.
625 if (isa<CXXConstructorDecl>(New) &&
626 New->getMinRequiredArguments() < Old->getMinRequiredArguments()) {
627 CXXSpecialMember NewSM = getSpecialMember(cast<CXXMethodDecl>(New)),
628 OldSM = getSpecialMember(cast<CXXMethodDecl>(Old));
629 if (NewSM != OldSM) {
630 ParmVarDecl *NewParam = New->getParamDecl(New->getMinRequiredArguments());
631 assert(NewParam->hasDefaultArg())((NewParam->hasDefaultArg()) ? static_cast<void> (0)
: __assert_fail ("NewParam->hasDefaultArg()", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 631, __PRETTY_FUNCTION__))
;
632 Diag(NewParam->getLocation(), diag::err_default_arg_makes_ctor_special)
633 << NewParam->getDefaultArgRange() << NewSM;
634 Diag(Old->getLocation(), diag::note_previous_declaration);
635 }
636 }
637
638 const FunctionDecl *Def;
639 // C++11 [dcl.constexpr]p1: If any declaration of a function or function
640 // template has a constexpr specifier then all its declarations shall
641 // contain the constexpr specifier.
642 if (New->getConstexprKind() != Old->getConstexprKind()) {
643 Diag(New->getLocation(), diag::err_constexpr_redecl_mismatch)
644 << New << New->getConstexprKind() << Old->getConstexprKind();
645 Diag(Old->getLocation(), diag::note_previous_declaration);
646 Invalid = true;
647 } else if (!Old->getMostRecentDecl()->isInlined() && New->isInlined() &&
648 Old->isDefined(Def) &&
649 // If a friend function is inlined but does not have 'inline'
650 // specifier, it is a definition. Do not report attribute conflict
651 // in this case, redefinition will be diagnosed later.
652 (New->isInlineSpecified() ||
653 New->getFriendObjectKind() == Decl::FOK_None)) {
654 // C++11 [dcl.fcn.spec]p4:
655 // If the definition of a function appears in a translation unit before its
656 // first declaration as inline, the program is ill-formed.
657 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
658 Diag(Def->getLocation(), diag::note_previous_definition);
659 Invalid = true;
660 }
661
662 // C++17 [temp.deduct.guide]p3:
663 // Two deduction guide declarations in the same translation unit
664 // for the same class template shall not have equivalent
665 // parameter-declaration-clauses.
666 if (isa<CXXDeductionGuideDecl>(New) &&
667 !New->isFunctionTemplateSpecialization()) {
668 Diag(New->getLocation(), diag::err_deduction_guide_redeclared);
669 Diag(Old->getLocation(), diag::note_previous_declaration);
670 }
671
672 // C++11 [dcl.fct.default]p4: If a friend declaration specifies a default
673 // argument expression, that declaration shall be a definition and shall be
674 // the only declaration of the function or function template in the
675 // translation unit.
676 if (Old->getFriendObjectKind() == Decl::FOK_Undeclared &&
677 functionDeclHasDefaultArgument(Old)) {
678 Diag(New->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
679 Diag(Old->getLocation(), diag::note_previous_declaration);
680 Invalid = true;
681 }
682
683 return Invalid;
684}
685
686NamedDecl *
687Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
688 MultiTemplateParamsArg TemplateParamLists) {
689 assert(D.isDecompositionDeclarator())((D.isDecompositionDeclarator()) ? static_cast<void> (0
) : __assert_fail ("D.isDecompositionDeclarator()", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 689, __PRETTY_FUNCTION__))
;
690 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
691
692 // The syntax only allows a decomposition declarator as a simple-declaration,
693 // a for-range-declaration, or a condition in Clang, but we parse it in more
694 // cases than that.
695 if (!D.mayHaveDecompositionDeclarator()) {
696 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
697 << Decomp.getSourceRange();
698 return nullptr;
699 }
700
701 if (!TemplateParamLists.empty()) {
702 // FIXME: There's no rule against this, but there are also no rules that
703 // would actually make it usable, so we reject it for now.
704 Diag(TemplateParamLists.front()->getTemplateLoc(),
705 diag::err_decomp_decl_template);
706 return nullptr;
707 }
708
709 Diag(Decomp.getLSquareLoc(),
710 !getLangOpts().CPlusPlus17
711 ? diag::ext_decomp_decl
712 : D.getContext() == DeclaratorContext::ConditionContext
713 ? diag::ext_decomp_decl_cond
714 : diag::warn_cxx14_compat_decomp_decl)
715 << Decomp.getSourceRange();
716
717 // The semantic context is always just the current context.
718 DeclContext *const DC = CurContext;
719
720 // C++17 [dcl.dcl]/8:
721 // The decl-specifier-seq shall contain only the type-specifier auto
722 // and cv-qualifiers.
723 // C++2a [dcl.dcl]/8:
724 // If decl-specifier-seq contains any decl-specifier other than static,
725 // thread_local, auto, or cv-qualifiers, the program is ill-formed.
726 auto &DS = D.getDeclSpec();
727 {
728 SmallVector<StringRef, 8> BadSpecifiers;
729 SmallVector<SourceLocation, 8> BadSpecifierLocs;
730 SmallVector<StringRef, 8> CPlusPlus20Specifiers;
731 SmallVector<SourceLocation, 8> CPlusPlus20SpecifierLocs;
732 if (auto SCS = DS.getStorageClassSpec()) {
733 if (SCS == DeclSpec::SCS_static) {
734 CPlusPlus20Specifiers.push_back(DeclSpec::getSpecifierName(SCS));
735 CPlusPlus20SpecifierLocs.push_back(DS.getStorageClassSpecLoc());
736 } else {
737 BadSpecifiers.push_back(DeclSpec::getSpecifierName(SCS));
738 BadSpecifierLocs.push_back(DS.getStorageClassSpecLoc());
739 }
740 }
741 if (auto TSCS = DS.getThreadStorageClassSpec()) {
742 CPlusPlus20Specifiers.push_back(DeclSpec::getSpecifierName(TSCS));
743 CPlusPlus20SpecifierLocs.push_back(DS.getThreadStorageClassSpecLoc());
744 }
745 if (DS.hasConstexprSpecifier()) {
746 BadSpecifiers.push_back(
747 DeclSpec::getSpecifierName(DS.getConstexprSpecifier()));
748 BadSpecifierLocs.push_back(DS.getConstexprSpecLoc());
749 }
750 if (DS.isInlineSpecified()) {
751 BadSpecifiers.push_back("inline");
752 BadSpecifierLocs.push_back(DS.getInlineSpecLoc());
753 }
754 if (!BadSpecifiers.empty()) {
755 auto &&Err = Diag(BadSpecifierLocs.front(), diag::err_decomp_decl_spec);
756 Err << (int)BadSpecifiers.size()
757 << llvm::join(BadSpecifiers.begin(), BadSpecifiers.end(), " ");
758 // Don't add FixItHints to remove the specifiers; we do still respect
759 // them when building the underlying variable.
760 for (auto Loc : BadSpecifierLocs)
761 Err << SourceRange(Loc, Loc);
762 } else if (!CPlusPlus20Specifiers.empty()) {
763 auto &&Warn = Diag(CPlusPlus20SpecifierLocs.front(),
764 getLangOpts().CPlusPlus2a
765 ? diag::warn_cxx17_compat_decomp_decl_spec
766 : diag::ext_decomp_decl_spec);
767 Warn << (int)CPlusPlus20Specifiers.size()
768 << llvm::join(CPlusPlus20Specifiers.begin(),
769 CPlusPlus20Specifiers.end(), " ");
770 for (auto Loc : CPlusPlus20SpecifierLocs)
771 Warn << SourceRange(Loc, Loc);
772 }
773 // We can't recover from it being declared as a typedef.
774 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
775 return nullptr;
776 }
777
778 // C++2a [dcl.struct.bind]p1:
779 // A cv that includes volatile is deprecated
780 if ((DS.getTypeQualifiers() & DeclSpec::TQ_volatile) &&
781 getLangOpts().CPlusPlus2a)
782 Diag(DS.getVolatileSpecLoc(),
783 diag::warn_deprecated_volatile_structured_binding);
784
785 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
786 QualType R = TInfo->getType();
787
788 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
789 UPPC_DeclarationType))
790 D.setInvalidType();
791
792 // The syntax only allows a single ref-qualifier prior to the decomposition
793 // declarator. No other declarator chunks are permitted. Also check the type
794 // specifier here.
795 if (DS.getTypeSpecType() != DeclSpec::TST_auto ||
796 D.hasGroupingParens() || D.getNumTypeObjects() > 1 ||
797 (D.getNumTypeObjects() == 1 &&
798 D.getTypeObject(0).Kind != DeclaratorChunk::Reference)) {
799 Diag(Decomp.getLSquareLoc(),
800 (D.hasGroupingParens() ||
801 (D.getNumTypeObjects() &&
802 D.getTypeObject(0).Kind == DeclaratorChunk::Paren))
803 ? diag::err_decomp_decl_parens
804 : diag::err_decomp_decl_type)
805 << R;
806
807 // In most cases, there's no actual problem with an explicitly-specified
808 // type, but a function type won't work here, and ActOnVariableDeclarator
809 // shouldn't be called for such a type.
810 if (R->isFunctionType())
811 D.setInvalidType();
812 }
813
814 // Build the BindingDecls.
815 SmallVector<BindingDecl*, 8> Bindings;
816
817 // Build the BindingDecls.
818 for (auto &B : D.getDecompositionDeclarator().bindings()) {
819 // Check for name conflicts.
820 DeclarationNameInfo NameInfo(B.Name, B.NameLoc);
821 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
822 ForVisibleRedeclaration);
823 LookupName(Previous, S,
824 /*CreateBuiltins*/DC->getRedeclContext()->isTranslationUnit());
825
826 // It's not permitted to shadow a template parameter name.
827 if (Previous.isSingleResult() &&
828 Previous.getFoundDecl()->isTemplateParameter()) {
829 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
830 Previous.getFoundDecl());
831 Previous.clear();
832 }
833
834 bool ConsiderLinkage = DC->isFunctionOrMethod() &&
835 DS.getStorageClassSpec() == DeclSpec::SCS_extern;
836 FilterLookupForScope(Previous, DC, S, ConsiderLinkage,
837 /*AllowInlineNamespace*/false);
838 if (!Previous.empty()) {
839 auto *Old = Previous.getRepresentativeDecl();
840 Diag(B.NameLoc, diag::err_redefinition) << B.Name;
841 Diag(Old->getLocation(), diag::note_previous_definition);
842 }
843
844 auto *BD = BindingDecl::Create(Context, DC, B.NameLoc, B.Name);
845 PushOnScopeChains(BD, S, true);
846 Bindings.push_back(BD);
847 ParsingInitForAutoVars.insert(BD);
848 }
849
850 // There are no prior lookup results for the variable itself, because it
851 // is unnamed.
852 DeclarationNameInfo NameInfo((IdentifierInfo *)nullptr,
853 Decomp.getLSquareLoc());
854 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
855 ForVisibleRedeclaration);
856
857 // Build the variable that holds the non-decomposed object.
858 bool AddToScope = true;
859 NamedDecl *New =
860 ActOnVariableDeclarator(S, D, DC, TInfo, Previous,
861 MultiTemplateParamsArg(), AddToScope, Bindings);
862 if (AddToScope) {
863 S->AddDecl(New);
864 CurContext->addHiddenDecl(New);
865 }
866
867 if (isInOpenMPDeclareTargetContext())
868 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
869
870 return New;
871}
872
873static bool checkSimpleDecomposition(
874 Sema &S, ArrayRef<BindingDecl *> Bindings, ValueDecl *Src,
875 QualType DecompType, const llvm::APSInt &NumElems, QualType ElemType,
876 llvm::function_ref<ExprResult(SourceLocation, Expr *, unsigned)> GetInit) {
877 if ((int64_t)Bindings.size() != NumElems) {
878 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
879 << DecompType << (unsigned)Bindings.size() << NumElems.toString(10)
880 << (NumElems < Bindings.size());
881 return true;
882 }
883
884 unsigned I = 0;
885 for (auto *B : Bindings) {
886 SourceLocation Loc = B->getLocation();
887 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
888 if (E.isInvalid())
889 return true;
890 E = GetInit(Loc, E.get(), I++);
891 if (E.isInvalid())
892 return true;
893 B->setBinding(ElemType, E.get());
894 }
895
896 return false;
897}
898
899static bool checkArrayLikeDecomposition(Sema &S,
900 ArrayRef<BindingDecl *> Bindings,
901 ValueDecl *Src, QualType DecompType,
902 const llvm::APSInt &NumElems,
903 QualType ElemType) {
904 return checkSimpleDecomposition(
905 S, Bindings, Src, DecompType, NumElems, ElemType,
906 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
907 ExprResult E = S.ActOnIntegerConstant(Loc, I);
908 if (E.isInvalid())
909 return ExprError();
910 return S.CreateBuiltinArraySubscriptExpr(Base, Loc, E.get(), Loc);
911 });
912}
913
914static bool checkArrayDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
915 ValueDecl *Src, QualType DecompType,
916 const ConstantArrayType *CAT) {
917 return checkArrayLikeDecomposition(S, Bindings, Src, DecompType,
918 llvm::APSInt(CAT->getSize()),
919 CAT->getElementType());
920}
921
922static bool checkVectorDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
923 ValueDecl *Src, QualType DecompType,
924 const VectorType *VT) {
925 return checkArrayLikeDecomposition(
926 S, Bindings, Src, DecompType, llvm::APSInt::get(VT->getNumElements()),
927 S.Context.getQualifiedType(VT->getElementType(),
928 DecompType.getQualifiers()));
929}
930
931static bool checkComplexDecomposition(Sema &S,
932 ArrayRef<BindingDecl *> Bindings,
933 ValueDecl *Src, QualType DecompType,
934 const ComplexType *CT) {
935 return checkSimpleDecomposition(
936 S, Bindings, Src, DecompType, llvm::APSInt::get(2),
937 S.Context.getQualifiedType(CT->getElementType(),
938 DecompType.getQualifiers()),
939 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
940 return S.CreateBuiltinUnaryOp(Loc, I ? UO_Imag : UO_Real, Base);
941 });
942}
943
944static std::string printTemplateArgs(const PrintingPolicy &PrintingPolicy,
945 TemplateArgumentListInfo &Args) {
946 SmallString<128> SS;
947 llvm::raw_svector_ostream OS(SS);
948 bool First = true;
949 for (auto &Arg : Args.arguments()) {
950 if (!First)
951 OS << ", ";
952 Arg.getArgument().print(PrintingPolicy, OS);
953 First = false;
954 }
955 return std::string(OS.str());
956}
957
958static bool lookupStdTypeTraitMember(Sema &S, LookupResult &TraitMemberLookup,
959 SourceLocation Loc, StringRef Trait,
960 TemplateArgumentListInfo &Args,
961 unsigned DiagID) {
962 auto DiagnoseMissing = [&] {
963 if (DiagID)
964 S.Diag(Loc, DiagID) << printTemplateArgs(S.Context.getPrintingPolicy(),
965 Args);
966 return true;
967 };
968
969 // FIXME: Factor out duplication with lookupPromiseType in SemaCoroutine.
970 NamespaceDecl *Std = S.getStdNamespace();
971 if (!Std)
972 return DiagnoseMissing();
973
974 // Look up the trait itself, within namespace std. We can diagnose various
975 // problems with this lookup even if we've been asked to not diagnose a
976 // missing specialization, because this can only fail if the user has been
977 // declaring their own names in namespace std or we don't support the
978 // standard library implementation in use.
979 LookupResult Result(S, &S.PP.getIdentifierTable().get(Trait),
980 Loc, Sema::LookupOrdinaryName);
981 if (!S.LookupQualifiedName(Result, Std))
982 return DiagnoseMissing();
983 if (Result.isAmbiguous())
984 return true;
985
986 ClassTemplateDecl *TraitTD = Result.getAsSingle<ClassTemplateDecl>();
987 if (!TraitTD) {
988 Result.suppressDiagnostics();
989 NamedDecl *Found = *Result.begin();
990 S.Diag(Loc, diag::err_std_type_trait_not_class_template) << Trait;
991 S.Diag(Found->getLocation(), diag::note_declared_at);
992 return true;
993 }
994
995 // Build the template-id.
996 QualType TraitTy = S.CheckTemplateIdType(TemplateName(TraitTD), Loc, Args);
997 if (TraitTy.isNull())
998 return true;
999 if (!S.isCompleteType(Loc, TraitTy)) {
1000 if (DiagID)
1001 S.RequireCompleteType(
1002 Loc, TraitTy, DiagID,
1003 printTemplateArgs(S.Context.getPrintingPolicy(), Args));
1004 return true;
1005 }
1006
1007 CXXRecordDecl *RD = TraitTy->getAsCXXRecordDecl();
1008 assert(RD && "specialization of class template is not a class?")((RD && "specialization of class template is not a class?"
) ? static_cast<void> (0) : __assert_fail ("RD && \"specialization of class template is not a class?\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 1008, __PRETTY_FUNCTION__))
;
1009
1010 // Look up the member of the trait type.
1011 S.LookupQualifiedName(TraitMemberLookup, RD);
1012 return TraitMemberLookup.isAmbiguous();
1013}
1014
1015static TemplateArgumentLoc
1016getTrivialIntegralTemplateArgument(Sema &S, SourceLocation Loc, QualType T,
1017 uint64_t I) {
1018 TemplateArgument Arg(S.Context, S.Context.MakeIntValue(I, T), T);
1019 return S.getTrivialTemplateArgumentLoc(Arg, T, Loc);
1020}
1021
1022static TemplateArgumentLoc
1023getTrivialTypeTemplateArgument(Sema &S, SourceLocation Loc, QualType T) {
1024 return S.getTrivialTemplateArgumentLoc(TemplateArgument(T), QualType(), Loc);
1025}
1026
1027namespace { enum class IsTupleLike { TupleLike, NotTupleLike, Error }; }
1028
1029static IsTupleLike isTupleLike(Sema &S, SourceLocation Loc, QualType T,
1030 llvm::APSInt &Size) {
1031 EnterExpressionEvaluationContext ContextRAII(
1032 S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
1033
1034 DeclarationName Value = S.PP.getIdentifierInfo("value");
1035 LookupResult R(S, Value, Loc, Sema::LookupOrdinaryName);
1036
1037 // Form template argument list for tuple_size<T>.
1038 TemplateArgumentListInfo Args(Loc, Loc);
1039 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
1040
1041 // If there's no tuple_size specialization or the lookup of 'value' is empty,
1042 // it's not tuple-like.
1043 if (lookupStdTypeTraitMember(S, R, Loc, "tuple_size", Args, /*DiagID*/ 0) ||
1044 R.empty())
1045 return IsTupleLike::NotTupleLike;
1046
1047 // If we get this far, we've committed to the tuple interpretation, but
1048 // we can still fail if there actually isn't a usable ::value.
1049
1050 struct ICEDiagnoser : Sema::VerifyICEDiagnoser {
1051 LookupResult &R;
1052 TemplateArgumentListInfo &Args;
1053 ICEDiagnoser(LookupResult &R, TemplateArgumentListInfo &Args)
1054 : R(R), Args(Args) {}
1055 void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) {
1056 S.Diag(Loc, diag::err_decomp_decl_std_tuple_size_not_constant)
1057 << printTemplateArgs(S.Context.getPrintingPolicy(), Args);
1058 }
1059 } Diagnoser(R, Args);
1060
1061 ExprResult E =
1062 S.BuildDeclarationNameExpr(CXXScopeSpec(), R, /*NeedsADL*/false);
1063 if (E.isInvalid())
1064 return IsTupleLike::Error;
1065
1066 E = S.VerifyIntegerConstantExpression(E.get(), &Size, Diagnoser, false);
1067 if (E.isInvalid())
1068 return IsTupleLike::Error;
1069
1070 return IsTupleLike::TupleLike;
1071}
1072
1073/// \return std::tuple_element<I, T>::type.
1074static QualType getTupleLikeElementType(Sema &S, SourceLocation Loc,
1075 unsigned I, QualType T) {
1076 // Form template argument list for tuple_element<I, T>.
1077 TemplateArgumentListInfo Args(Loc, Loc);
1078 Args.addArgument(
1079 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1080 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
1081
1082 DeclarationName TypeDN = S.PP.getIdentifierInfo("type");
1083 LookupResult R(S, TypeDN, Loc, Sema::LookupOrdinaryName);
1084 if (lookupStdTypeTraitMember(
1085 S, R, Loc, "tuple_element", Args,
1086 diag::err_decomp_decl_std_tuple_element_not_specialized))
1087 return QualType();
1088
1089 auto *TD = R.getAsSingle<TypeDecl>();
1090 if (!TD) {
1091 R.suppressDiagnostics();
1092 S.Diag(Loc, diag::err_decomp_decl_std_tuple_element_not_specialized)
1093 << printTemplateArgs(S.Context.getPrintingPolicy(), Args);
1094 if (!R.empty())
1095 S.Diag(R.getRepresentativeDecl()->getLocation(), diag::note_declared_at);
1096 return QualType();
1097 }
1098
1099 return S.Context.getTypeDeclType(TD);
1100}
1101
1102namespace {
1103struct BindingDiagnosticTrap {
1104 Sema &S;
1105 DiagnosticErrorTrap Trap;
1106 BindingDecl *BD;
1107
1108 BindingDiagnosticTrap(Sema &S, BindingDecl *BD)
1109 : S(S), Trap(S.Diags), BD(BD) {}
1110 ~BindingDiagnosticTrap() {
1111 if (Trap.hasErrorOccurred())
1112 S.Diag(BD->getLocation(), diag::note_in_binding_decl_init) << BD;
1113 }
1114};
1115}
1116
1117static bool checkTupleLikeDecomposition(Sema &S,
1118 ArrayRef<BindingDecl *> Bindings,
1119 VarDecl *Src, QualType DecompType,
1120 const llvm::APSInt &TupleSize) {
1121 if ((int64_t)Bindings.size() != TupleSize) {
1122 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1123 << DecompType << (unsigned)Bindings.size() << TupleSize.toString(10)
1124 << (TupleSize < Bindings.size());
1125 return true;
1126 }
1127
1128 if (Bindings.empty())
1129 return false;
1130
1131 DeclarationName GetDN = S.PP.getIdentifierInfo("get");
1132
1133 // [dcl.decomp]p3:
1134 // The unqualified-id get is looked up in the scope of E by class member
1135 // access lookup ...
1136 LookupResult MemberGet(S, GetDN, Src->getLocation(), Sema::LookupMemberName);
1137 bool UseMemberGet = false;
1138 if (S.isCompleteType(Src->getLocation(), DecompType)) {
1139 if (auto *RD = DecompType->getAsCXXRecordDecl())
1140 S.LookupQualifiedName(MemberGet, RD);
1141 if (MemberGet.isAmbiguous())
1142 return true;
1143 // ... and if that finds at least one declaration that is a function
1144 // template whose first template parameter is a non-type parameter ...
1145 for (NamedDecl *D : MemberGet) {
1146 if (FunctionTemplateDecl *FTD =
1147 dyn_cast<FunctionTemplateDecl>(D->getUnderlyingDecl())) {
1148 TemplateParameterList *TPL = FTD->getTemplateParameters();
1149 if (TPL->size() != 0 &&
1150 isa<NonTypeTemplateParmDecl>(TPL->getParam(0))) {
1151 // ... the initializer is e.get<i>().
1152 UseMemberGet = true;
1153 break;
1154 }
1155 }
1156 }
1157 }
1158
1159 unsigned I = 0;
1160 for (auto *B : Bindings) {
1161 BindingDiagnosticTrap Trap(S, B);
1162 SourceLocation Loc = B->getLocation();
1163
1164 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1165 if (E.isInvalid())
1166 return true;
1167
1168 // e is an lvalue if the type of the entity is an lvalue reference and
1169 // an xvalue otherwise
1170 if (!Src->getType()->isLValueReferenceType())
1171 E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), CK_NoOp,
1172 E.get(), nullptr, VK_XValue);
1173
1174 TemplateArgumentListInfo Args(Loc, Loc);
1175 Args.addArgument(
1176 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1177
1178 if (UseMemberGet) {
1179 // if [lookup of member get] finds at least one declaration, the
1180 // initializer is e.get<i-1>().
1181 E = S.BuildMemberReferenceExpr(E.get(), DecompType, Loc, false,
1182 CXXScopeSpec(), SourceLocation(), nullptr,
1183 MemberGet, &Args, nullptr);
1184 if (E.isInvalid())
1185 return true;
1186
1187 E = S.BuildCallExpr(nullptr, E.get(), Loc, None, Loc);
1188 } else {
1189 // Otherwise, the initializer is get<i-1>(e), where get is looked up
1190 // in the associated namespaces.
1191 Expr *Get = UnresolvedLookupExpr::Create(
1192 S.Context, nullptr, NestedNameSpecifierLoc(), SourceLocation(),
1193 DeclarationNameInfo(GetDN, Loc), /*RequiresADL*/true, &Args,
1194 UnresolvedSetIterator(), UnresolvedSetIterator());
1195
1196 Expr *Arg = E.get();
1197 E = S.BuildCallExpr(nullptr, Get, Loc, Arg, Loc);
1198 }
1199 if (E.isInvalid())
1200 return true;
1201 Expr *Init = E.get();
1202
1203 // Given the type T designated by std::tuple_element<i - 1, E>::type,
1204 QualType T = getTupleLikeElementType(S, Loc, I, DecompType);
1205 if (T.isNull())
1206 return true;
1207
1208 // each vi is a variable of type "reference to T" initialized with the
1209 // initializer, where the reference is an lvalue reference if the
1210 // initializer is an lvalue and an rvalue reference otherwise
1211 QualType RefType =
1212 S.BuildReferenceType(T, E.get()->isLValue(), Loc, B->getDeclName());
1213 if (RefType.isNull())
1214 return true;
1215 auto *RefVD = VarDecl::Create(
1216 S.Context, Src->getDeclContext(), Loc, Loc,
1217 B->getDeclName().getAsIdentifierInfo(), RefType,
1218 S.Context.getTrivialTypeSourceInfo(T, Loc), Src->getStorageClass());
1219 RefVD->setLexicalDeclContext(Src->getLexicalDeclContext());
1220 RefVD->setTSCSpec(Src->getTSCSpec());
1221 RefVD->setImplicit();
1222 if (Src->isInlineSpecified())
1223 RefVD->setInlineSpecified();
1224 RefVD->getLexicalDeclContext()->addHiddenDecl(RefVD);
1225
1226 InitializedEntity Entity = InitializedEntity::InitializeBinding(RefVD);
1227 InitializationKind Kind = InitializationKind::CreateCopy(Loc, Loc);
1228 InitializationSequence Seq(S, Entity, Kind, Init);
1229 E = Seq.Perform(S, Entity, Kind, Init);
1230 if (E.isInvalid())
1231 return true;
1232 E = S.ActOnFinishFullExpr(E.get(), Loc, /*DiscardedValue*/ false);
1233 if (E.isInvalid())
1234 return true;
1235 RefVD->setInit(E.get());
1236 if (!E.get()->isValueDependent())
1237 RefVD->checkInitIsICE();
1238
1239 E = S.BuildDeclarationNameExpr(CXXScopeSpec(),
1240 DeclarationNameInfo(B->getDeclName(), Loc),
1241 RefVD);
1242 if (E.isInvalid())
1243 return true;
1244
1245 B->setBinding(T, E.get());
1246 I++;
1247 }
1248
1249 return false;
1250}
1251
1252/// Find the base class to decompose in a built-in decomposition of a class type.
1253/// This base class search is, unfortunately, not quite like any other that we
1254/// perform anywhere else in C++.
1255static DeclAccessPair findDecomposableBaseClass(Sema &S, SourceLocation Loc,
1256 const CXXRecordDecl *RD,
1257 CXXCastPath &BasePath) {
1258 auto BaseHasFields = [](const CXXBaseSpecifier *Specifier,
1259 CXXBasePath &Path) {
1260 return Specifier->getType()->getAsCXXRecordDecl()->hasDirectFields();
1261 };
1262
1263 const CXXRecordDecl *ClassWithFields = nullptr;
1264 AccessSpecifier AS = AS_public;
1265 if (RD->hasDirectFields())
1266 // [dcl.decomp]p4:
1267 // Otherwise, all of E's non-static data members shall be public direct
1268 // members of E ...
1269 ClassWithFields = RD;
1270 else {
1271 // ... or of ...
1272 CXXBasePaths Paths;
1273 Paths.setOrigin(const_cast<CXXRecordDecl*>(RD));
1274 if (!RD->lookupInBases(BaseHasFields, Paths)) {
1275 // If no classes have fields, just decompose RD itself. (This will work
1276 // if and only if zero bindings were provided.)
1277 return DeclAccessPair::make(const_cast<CXXRecordDecl*>(RD), AS_public);
1278 }
1279
1280 CXXBasePath *BestPath = nullptr;
1281 for (auto &P : Paths) {
1282 if (!BestPath)
1283 BestPath = &P;
1284 else if (!S.Context.hasSameType(P.back().Base->getType(),
1285 BestPath->back().Base->getType())) {
1286 // ... the same ...
1287 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1288 << false << RD << BestPath->back().Base->getType()
1289 << P.back().Base->getType();
1290 return DeclAccessPair();
1291 } else if (P.Access < BestPath->Access) {
1292 BestPath = &P;
1293 }
1294 }
1295
1296 // ... unambiguous ...
1297 QualType BaseType = BestPath->back().Base->getType();
1298 if (Paths.isAmbiguous(S.Context.getCanonicalType(BaseType))) {
1299 S.Diag(Loc, diag::err_decomp_decl_ambiguous_base)
1300 << RD << BaseType << S.getAmbiguousPathsDisplayString(Paths);
1301 return DeclAccessPair();
1302 }
1303
1304 // ... [accessible, implied by other rules] base class of E.
1305 S.CheckBaseClassAccess(Loc, BaseType, S.Context.getRecordType(RD),
1306 *BestPath, diag::err_decomp_decl_inaccessible_base);
1307 AS = BestPath->Access;
1308
1309 ClassWithFields = BaseType->getAsCXXRecordDecl();
1310 S.BuildBasePathArray(Paths, BasePath);
1311 }
1312
1313 // The above search did not check whether the selected class itself has base
1314 // classes with fields, so check that now.
1315 CXXBasePaths Paths;
1316 if (ClassWithFields->lookupInBases(BaseHasFields, Paths)) {
1317 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1318 << (ClassWithFields == RD) << RD << ClassWithFields
1319 << Paths.front().back().Base->getType();
1320 return DeclAccessPair();
1321 }
1322
1323 return DeclAccessPair::make(const_cast<CXXRecordDecl*>(ClassWithFields), AS);
1324}
1325
1326static bool checkMemberDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
1327 ValueDecl *Src, QualType DecompType,
1328 const CXXRecordDecl *OrigRD) {
1329 if (S.RequireCompleteType(Src->getLocation(), DecompType,
1330 diag::err_incomplete_type))
1331 return true;
1332
1333 CXXCastPath BasePath;
1334 DeclAccessPair BasePair =
1335 findDecomposableBaseClass(S, Src->getLocation(), OrigRD, BasePath);
1336 const CXXRecordDecl *RD = cast_or_null<CXXRecordDecl>(BasePair.getDecl());
1337 if (!RD)
1338 return true;
1339 QualType BaseType = S.Context.getQualifiedType(S.Context.getRecordType(RD),
1340 DecompType.getQualifiers());
1341
1342 auto DiagnoseBadNumberOfBindings = [&]() -> bool {
1343 unsigned NumFields =
1344 std::count_if(RD->field_begin(), RD->field_end(),
1345 [](FieldDecl *FD) { return !FD->isUnnamedBitfield(); });
1346 assert(Bindings.size() != NumFields)((Bindings.size() != NumFields) ? static_cast<void> (0)
: __assert_fail ("Bindings.size() != NumFields", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 1346, __PRETTY_FUNCTION__))
;
1347 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1348 << DecompType << (unsigned)Bindings.size() << NumFields
1349 << (NumFields < Bindings.size());
1350 return true;
1351 };
1352
1353 // all of E's non-static data members shall be [...] well-formed
1354 // when named as e.name in the context of the structured binding,
1355 // E shall not have an anonymous union member, ...
1356 unsigned I = 0;
1357 for (auto *FD : RD->fields()) {
1358 if (FD->isUnnamedBitfield())
1359 continue;
1360
1361 if (FD->isAnonymousStructOrUnion()) {
1362 S.Diag(Src->getLocation(), diag::err_decomp_decl_anon_union_member)
1363 << DecompType << FD->getType()->isUnionType();
1364 S.Diag(FD->getLocation(), diag::note_declared_at);
1365 return true;
1366 }
1367
1368 // We have a real field to bind.
1369 if (I >= Bindings.size())
1370 return DiagnoseBadNumberOfBindings();
1371 auto *B = Bindings[I++];
1372 SourceLocation Loc = B->getLocation();
1373
1374 // The field must be accessible in the context of the structured binding.
1375 // We already checked that the base class is accessible.
1376 // FIXME: Add 'const' to AccessedEntity's classes so we can remove the
1377 // const_cast here.
1378 S.CheckStructuredBindingMemberAccess(
1379 Loc, const_cast<CXXRecordDecl *>(OrigRD),
1380 DeclAccessPair::make(FD, CXXRecordDecl::MergeAccess(
1381 BasePair.getAccess(), FD->getAccess())));
1382
1383 // Initialize the binding to Src.FD.
1384 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1385 if (E.isInvalid())
1386 return true;
1387 E = S.ImpCastExprToType(E.get(), BaseType, CK_UncheckedDerivedToBase,
1388 VK_LValue, &BasePath);
1389 if (E.isInvalid())
1390 return true;
1391 E = S.BuildFieldReferenceExpr(E.get(), /*IsArrow*/ false, Loc,
1392 CXXScopeSpec(), FD,
1393 DeclAccessPair::make(FD, FD->getAccess()),
1394 DeclarationNameInfo(FD->getDeclName(), Loc));
1395 if (E.isInvalid())
1396 return true;
1397
1398 // If the type of the member is T, the referenced type is cv T, where cv is
1399 // the cv-qualification of the decomposition expression.
1400 //
1401 // FIXME: We resolve a defect here: if the field is mutable, we do not add
1402 // 'const' to the type of the field.
1403 Qualifiers Q = DecompType.getQualifiers();
1404 if (FD->isMutable())
1405 Q.removeConst();
1406 B->setBinding(S.BuildQualifiedType(FD->getType(), Loc, Q), E.get());
1407 }
1408
1409 if (I != Bindings.size())
1410 return DiagnoseBadNumberOfBindings();
1411
1412 return false;
1413}
1414
1415void Sema::CheckCompleteDecompositionDeclaration(DecompositionDecl *DD) {
1416 QualType DecompType = DD->getType();
1417
1418 // If the type of the decomposition is dependent, then so is the type of
1419 // each binding.
1420 if (DecompType->isDependentType()) {
1421 for (auto *B : DD->bindings())
1422 B->setType(Context.DependentTy);
1423 return;
1424 }
1425
1426 DecompType = DecompType.getNonReferenceType();
1427 ArrayRef<BindingDecl*> Bindings = DD->bindings();
1428
1429 // C++1z [dcl.decomp]/2:
1430 // If E is an array type [...]
1431 // As an extension, we also support decomposition of built-in complex and
1432 // vector types.
1433 if (auto *CAT = Context.getAsConstantArrayType(DecompType)) {
1434 if (checkArrayDecomposition(*this, Bindings, DD, DecompType, CAT))
1435 DD->setInvalidDecl();
1436 return;
1437 }
1438 if (auto *VT = DecompType->getAs<VectorType>()) {
1439 if (checkVectorDecomposition(*this, Bindings, DD, DecompType, VT))
1440 DD->setInvalidDecl();
1441 return;
1442 }
1443 if (auto *CT = DecompType->getAs<ComplexType>()) {
1444 if (checkComplexDecomposition(*this, Bindings, DD, DecompType, CT))
1445 DD->setInvalidDecl();
1446 return;
1447 }
1448
1449 // C++1z [dcl.decomp]/3:
1450 // if the expression std::tuple_size<E>::value is a well-formed integral
1451 // constant expression, [...]
1452 llvm::APSInt TupleSize(32);
1453 switch (isTupleLike(*this, DD->getLocation(), DecompType, TupleSize)) {
1454 case IsTupleLike::Error:
1455 DD->setInvalidDecl();
1456 return;
1457
1458 case IsTupleLike::TupleLike:
1459 if (checkTupleLikeDecomposition(*this, Bindings, DD, DecompType, TupleSize))
1460 DD->setInvalidDecl();
1461 return;
1462
1463 case IsTupleLike::NotTupleLike:
1464 break;
1465 }
1466
1467 // C++1z [dcl.dcl]/8:
1468 // [E shall be of array or non-union class type]
1469 CXXRecordDecl *RD = DecompType->getAsCXXRecordDecl();
1470 if (!RD || RD->isUnion()) {
1471 Diag(DD->getLocation(), diag::err_decomp_decl_unbindable_type)
1472 << DD << !RD << DecompType;
1473 DD->setInvalidDecl();
1474 return;
1475 }
1476
1477 // C++1z [dcl.decomp]/4:
1478 // all of E's non-static data members shall be [...] direct members of
1479 // E or of the same unambiguous public base class of E, ...
1480 if (checkMemberDecomposition(*this, Bindings, DD, DecompType, RD))
1481 DD->setInvalidDecl();
1482}
1483
1484/// Merge the exception specifications of two variable declarations.
1485///
1486/// This is called when there's a redeclaration of a VarDecl. The function
1487/// checks if the redeclaration might have an exception specification and
1488/// validates compatibility and merges the specs if necessary.
1489void Sema::MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old) {
1490 // Shortcut if exceptions are disabled.
1491 if (!getLangOpts().CXXExceptions)
1492 return;
1493
1494 assert(Context.hasSameType(New->getType(), Old->getType()) &&((Context.hasSameType(New->getType(), Old->getType()) &&
"Should only be called if types are otherwise the same.") ? static_cast
<void> (0) : __assert_fail ("Context.hasSameType(New->getType(), Old->getType()) && \"Should only be called if types are otherwise the same.\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 1495, __PRETTY_FUNCTION__))
1495 "Should only be called if types are otherwise the same.")((Context.hasSameType(New->getType(), Old->getType()) &&
"Should only be called if types are otherwise the same.") ? static_cast
<void> (0) : __assert_fail ("Context.hasSameType(New->getType(), Old->getType()) && \"Should only be called if types are otherwise the same.\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 1495, __PRETTY_FUNCTION__))
;
1496
1497 QualType NewType = New->getType();
1498 QualType OldType = Old->getType();
1499
1500 // We're only interested in pointers and references to functions, as well
1501 // as pointers to member functions.
1502 if (const ReferenceType *R = NewType->getAs<ReferenceType>()) {
1503 NewType = R->getPointeeType();
1504 OldType = OldType->castAs<ReferenceType>()->getPointeeType();
1505 } else if (const PointerType *P = NewType->getAs<PointerType>()) {
1506 NewType = P->getPointeeType();
1507 OldType = OldType->castAs<PointerType>()->getPointeeType();
1508 } else if (const MemberPointerType *M = NewType->getAs<MemberPointerType>()) {
1509 NewType = M->getPointeeType();
1510 OldType = OldType->castAs<MemberPointerType>()->getPointeeType();
1511 }
1512
1513 if (!NewType->isFunctionProtoType())
1514 return;
1515
1516 // There's lots of special cases for functions. For function pointers, system
1517 // libraries are hopefully not as broken so that we don't need these
1518 // workarounds.
1519 if (CheckEquivalentExceptionSpec(
1520 OldType->getAs<FunctionProtoType>(), Old->getLocation(),
1521 NewType->getAs<FunctionProtoType>(), New->getLocation())) {
1522 New->setInvalidDecl();
1523 }
1524}
1525
1526/// CheckCXXDefaultArguments - Verify that the default arguments for a
1527/// function declaration are well-formed according to C++
1528/// [dcl.fct.default].
1529void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) {
1530 unsigned NumParams = FD->getNumParams();
1531 unsigned p;
1532
1533 // Find first parameter with a default argument
1534 for (p = 0; p < NumParams; ++p) {
1535 ParmVarDecl *Param = FD->getParamDecl(p);
1536 if (Param->hasDefaultArg())
1537 break;
1538 }
1539
1540 // C++11 [dcl.fct.default]p4:
1541 // In a given function declaration, each parameter subsequent to a parameter
1542 // with a default argument shall have a default argument supplied in this or
1543 // a previous declaration or shall be a function parameter pack. A default
1544 // argument shall not be redefined by a later declaration (not even to the
1545 // same value).
1546 unsigned LastMissingDefaultArg = 0;
1547 for (; p < NumParams; ++p) {
1548 ParmVarDecl *Param = FD->getParamDecl(p);
1549 if (!Param->hasDefaultArg() && !Param->isParameterPack()) {
1550 if (Param->isInvalidDecl())
1551 /* We already complained about this parameter. */;
1552 else if (Param->getIdentifier())
1553 Diag(Param->getLocation(),
1554 diag::err_param_default_argument_missing_name)
1555 << Param->getIdentifier();
1556 else
1557 Diag(Param->getLocation(),
1558 diag::err_param_default_argument_missing);
1559
1560 LastMissingDefaultArg = p;
1561 }
1562 }
1563
1564 if (LastMissingDefaultArg > 0) {
1565 // Some default arguments were missing. Clear out all of the
1566 // default arguments up to (and including) the last missing
1567 // default argument, so that we leave the function parameters
1568 // in a semantically valid state.
1569 for (p = 0; p <= LastMissingDefaultArg; ++p) {
1570 ParmVarDecl *Param = FD->getParamDecl(p);
1571 if (Param->hasDefaultArg()) {
1572 Param->setDefaultArg(nullptr);
1573 }
1574 }
1575 }
1576}
1577
1578/// Check that the given type is a literal type. Issue a diagnostic if not,
1579/// if Kind is Diagnose.
1580/// \return \c true if a problem has been found (and optionally diagnosed).
1581template <typename... Ts>
1582static bool CheckLiteralType(Sema &SemaRef, Sema::CheckConstexprKind Kind,
1583 SourceLocation Loc, QualType T, unsigned DiagID,
1584 Ts &&...DiagArgs) {
1585 if (T->isDependentType())
1586 return false;
1587
1588 switch (Kind) {
1589 case Sema::CheckConstexprKind::Diagnose:
1590 return SemaRef.RequireLiteralType(Loc, T, DiagID,
1591 std::forward<Ts>(DiagArgs)...);
1592
1593 case Sema::CheckConstexprKind::CheckValid:
1594 return !T->isLiteralType(SemaRef.Context);
1595 }
1596
1597 llvm_unreachable("unknown CheckConstexprKind")::llvm::llvm_unreachable_internal("unknown CheckConstexprKind"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 1597)
;
1598}
1599
1600/// Determine whether a destructor cannot be constexpr due to
1601static bool CheckConstexprDestructorSubobjects(Sema &SemaRef,
1602 const CXXDestructorDecl *DD,
1603 Sema::CheckConstexprKind Kind) {
1604 auto Check = [&](SourceLocation Loc, QualType T, const FieldDecl *FD) {
1605 const CXXRecordDecl *RD =
1606 T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
1607 if (!RD || RD->hasConstexprDestructor())
1608 return true;
1609
1610 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1611 SemaRef.Diag(DD->getLocation(), diag::err_constexpr_dtor_subobject)
1612 << DD->getConstexprKind() << !FD
1613 << (FD ? FD->getDeclName() : DeclarationName()) << T;
1614 SemaRef.Diag(Loc, diag::note_constexpr_dtor_subobject)
1615 << !FD << (FD ? FD->getDeclName() : DeclarationName()) << T;
1616 }
1617 return false;
1618 };
1619
1620 const CXXRecordDecl *RD = DD->getParent();
1621 for (const CXXBaseSpecifier &B : RD->bases())
1622 if (!Check(B.getBaseTypeLoc(), B.getType(), nullptr))
1623 return false;
1624 for (const FieldDecl *FD : RD->fields())
1625 if (!Check(FD->getLocation(), FD->getType(), FD))
1626 return false;
1627 return true;
1628}
1629
1630/// Check whether a function's parameter types are all literal types. If so,
1631/// return true. If not, produce a suitable diagnostic and return false.
1632static bool CheckConstexprParameterTypes(Sema &SemaRef,
1633 const FunctionDecl *FD,
1634 Sema::CheckConstexprKind Kind) {
1635 unsigned ArgIndex = 0;
1636 const auto *FT = FD->getType()->castAs<FunctionProtoType>();
1637 for (FunctionProtoType::param_type_iterator i = FT->param_type_begin(),
1638 e = FT->param_type_end();
1639 i != e; ++i, ++ArgIndex) {
1640 const ParmVarDecl *PD = FD->getParamDecl(ArgIndex);
1641 SourceLocation ParamLoc = PD->getLocation();
1642 if (CheckLiteralType(SemaRef, Kind, ParamLoc, *i,
1643 diag::err_constexpr_non_literal_param, ArgIndex + 1,
1644 PD->getSourceRange(), isa<CXXConstructorDecl>(FD),
1645 FD->isConsteval()))
1646 return false;
1647 }
1648 return true;
1649}
1650
1651/// Check whether a function's return type is a literal type. If so, return
1652/// true. If not, produce a suitable diagnostic and return false.
1653static bool CheckConstexprReturnType(Sema &SemaRef, const FunctionDecl *FD,
1654 Sema::CheckConstexprKind Kind) {
1655 if (CheckLiteralType(SemaRef, Kind, FD->getLocation(), FD->getReturnType(),
1656 diag::err_constexpr_non_literal_return,
1657 FD->isConsteval()))
1658 return false;
1659 return true;
1660}
1661
1662/// Get diagnostic %select index for tag kind for
1663/// record diagnostic message.
1664/// WARNING: Indexes apply to particular diagnostics only!
1665///
1666/// \returns diagnostic %select index.
1667static unsigned getRecordDiagFromTagKind(TagTypeKind Tag) {
1668 switch (Tag) {
1669 case TTK_Struct: return 0;
1670 case TTK_Interface: return 1;
1671 case TTK_Class: return 2;
1672 default: llvm_unreachable("Invalid tag kind for record diagnostic!")::llvm::llvm_unreachable_internal("Invalid tag kind for record diagnostic!"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 1672)
;
1673 }
1674}
1675
1676static bool CheckConstexprFunctionBody(Sema &SemaRef, const FunctionDecl *Dcl,
1677 Stmt *Body,
1678 Sema::CheckConstexprKind Kind);
1679
1680// Check whether a function declaration satisfies the requirements of a
1681// constexpr function definition or a constexpr constructor definition. If so,
1682// return true. If not, produce appropriate diagnostics (unless asked not to by
1683// Kind) and return false.
1684//
1685// This implements C++11 [dcl.constexpr]p3,4, as amended by DR1360.
1686bool Sema::CheckConstexprFunctionDefinition(const FunctionDecl *NewFD,
1687 CheckConstexprKind Kind) {
1688 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
1689 if (MD && MD->isInstance()) {
1690 // C++11 [dcl.constexpr]p4:
1691 // The definition of a constexpr constructor shall satisfy the following
1692 // constraints:
1693 // - the class shall not have any virtual base classes;
1694 //
1695 // FIXME: This only applies to constructors and destructors, not arbitrary
1696 // member functions.
1697 const CXXRecordDecl *RD = MD->getParent();
1698 if (RD->getNumVBases()) {
1699 if (Kind == CheckConstexprKind::CheckValid)
1700 return false;
1701
1702 Diag(NewFD->getLocation(), diag::err_constexpr_virtual_base)
1703 << isa<CXXConstructorDecl>(NewFD)
1704 << getRecordDiagFromTagKind(RD->getTagKind()) << RD->getNumVBases();
1705 for (const auto &I : RD->vbases())
1706 Diag(I.getBeginLoc(), diag::note_constexpr_virtual_base_here)
1707 << I.getSourceRange();
1708 return false;
1709 }
1710 }
1711
1712 if (!isa<CXXConstructorDecl>(NewFD)) {
1713 // C++11 [dcl.constexpr]p3:
1714 // The definition of a constexpr function shall satisfy the following
1715 // constraints:
1716 // - it shall not be virtual; (removed in C++20)
1717 const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD);
1718 if (Method && Method->isVirtual()) {
1719 if (getLangOpts().CPlusPlus2a) {
1720 if (Kind == CheckConstexprKind::Diagnose)
1721 Diag(Method->getLocation(), diag::warn_cxx17_compat_constexpr_virtual);
1722 } else {
1723 if (Kind == CheckConstexprKind::CheckValid)
1724 return false;
1725
1726 Method = Method->getCanonicalDecl();
1727 Diag(Method->getLocation(), diag::err_constexpr_virtual);
1728
1729 // If it's not obvious why this function is virtual, find an overridden
1730 // function which uses the 'virtual' keyword.
1731 const CXXMethodDecl *WrittenVirtual = Method;
1732 while (!WrittenVirtual->isVirtualAsWritten())
1733 WrittenVirtual = *WrittenVirtual->begin_overridden_methods();
1734 if (WrittenVirtual != Method)
1735 Diag(WrittenVirtual->getLocation(),
1736 diag::note_overridden_virtual_function);
1737 return false;
1738 }
1739 }
1740
1741 // - its return type shall be a literal type;
1742 if (!CheckConstexprReturnType(*this, NewFD, Kind))
1743 return false;
1744 }
1745
1746 if (auto *Dtor = dyn_cast<CXXDestructorDecl>(NewFD)) {
1747 // A destructor can be constexpr only if the defaulted destructor could be;
1748 // we don't need to check the members and bases if we already know they all
1749 // have constexpr destructors.
1750 if (!Dtor->getParent()->defaultedDestructorIsConstexpr()) {
1751 if (Kind == CheckConstexprKind::CheckValid)
1752 return false;
1753 if (!CheckConstexprDestructorSubobjects(*this, Dtor, Kind))
1754 return false;
1755 }
1756 }
1757
1758 // - each of its parameter types shall be a literal type;
1759 if (!CheckConstexprParameterTypes(*this, NewFD, Kind))
1760 return false;
1761
1762 Stmt *Body = NewFD->getBody();
1763 assert(Body &&((Body && "CheckConstexprFunctionDefinition called on function with no body"
) ? static_cast<void> (0) : __assert_fail ("Body && \"CheckConstexprFunctionDefinition called on function with no body\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 1764, __PRETTY_FUNCTION__))
1764 "CheckConstexprFunctionDefinition called on function with no body")((Body && "CheckConstexprFunctionDefinition called on function with no body"
) ? static_cast<void> (0) : __assert_fail ("Body && \"CheckConstexprFunctionDefinition called on function with no body\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 1764, __PRETTY_FUNCTION__))
;
1765 return CheckConstexprFunctionBody(*this, NewFD, Body, Kind);
1766}
1767
1768/// Check the given declaration statement is legal within a constexpr function
1769/// body. C++11 [dcl.constexpr]p3,p4, and C++1y [dcl.constexpr]p3.
1770///
1771/// \return true if the body is OK (maybe only as an extension), false if we
1772/// have diagnosed a problem.
1773static bool CheckConstexprDeclStmt(Sema &SemaRef, const FunctionDecl *Dcl,
1774 DeclStmt *DS, SourceLocation &Cxx1yLoc,
1775 Sema::CheckConstexprKind Kind) {
1776 // C++11 [dcl.constexpr]p3 and p4:
1777 // The definition of a constexpr function(p3) or constructor(p4) [...] shall
1778 // contain only
1779 for (const auto *DclIt : DS->decls()) {
1780 switch (DclIt->getKind()) {
1781 case Decl::StaticAssert:
1782 case Decl::Using:
1783 case Decl::UsingShadow:
1784 case Decl::UsingDirective:
1785 case Decl::UnresolvedUsingTypename:
1786 case Decl::UnresolvedUsingValue:
1787 // - static_assert-declarations
1788 // - using-declarations,
1789 // - using-directives,
1790 continue;
1791
1792 case Decl::Typedef:
1793 case Decl::TypeAlias: {
1794 // - typedef declarations and alias-declarations that do not define
1795 // classes or enumerations,
1796 const auto *TN = cast<TypedefNameDecl>(DclIt);
1797 if (TN->getUnderlyingType()->isVariablyModifiedType()) {
1798 // Don't allow variably-modified types in constexpr functions.
1799 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1800 TypeLoc TL = TN->getTypeSourceInfo()->getTypeLoc();
1801 SemaRef.Diag(TL.getBeginLoc(), diag::err_constexpr_vla)
1802 << TL.getSourceRange() << TL.getType()
1803 << isa<CXXConstructorDecl>(Dcl);
1804 }
1805 return false;
1806 }
1807 continue;
1808 }
1809
1810 case Decl::Enum:
1811 case Decl::CXXRecord:
1812 // C++1y allows types to be defined, not just declared.
1813 if (cast<TagDecl>(DclIt)->isThisDeclarationADefinition()) {
1814 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1815 SemaRef.Diag(DS->getBeginLoc(),
1816 SemaRef.getLangOpts().CPlusPlus14
1817 ? diag::warn_cxx11_compat_constexpr_type_definition
1818 : diag::ext_constexpr_type_definition)
1819 << isa<CXXConstructorDecl>(Dcl);
1820 } else if (!SemaRef.getLangOpts().CPlusPlus14) {
1821 return false;
1822 }
1823 }
1824 continue;
1825
1826 case Decl::EnumConstant:
1827 case Decl::IndirectField:
1828 case Decl::ParmVar:
1829 // These can only appear with other declarations which are banned in
1830 // C++11 and permitted in C++1y, so ignore them.
1831 continue;
1832
1833 case Decl::Var:
1834 case Decl::Decomposition: {
1835 // C++1y [dcl.constexpr]p3 allows anything except:
1836 // a definition of a variable of non-literal type or of static or
1837 // thread storage duration or [before C++2a] for which no
1838 // initialization is performed.
1839 const auto *VD = cast<VarDecl>(DclIt);
1840 if (VD->isThisDeclarationADefinition()) {
1841 if (VD->isStaticLocal()) {
1842 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1843 SemaRef.Diag(VD->getLocation(),
1844 diag::err_constexpr_local_var_static)
1845 << isa<CXXConstructorDecl>(Dcl)
1846 << (VD->getTLSKind() == VarDecl::TLS_Dynamic);
1847 }
1848 return false;
1849 }
1850 if (CheckLiteralType(SemaRef, Kind, VD->getLocation(), VD->getType(),
1851 diag::err_constexpr_local_var_non_literal_type,
1852 isa<CXXConstructorDecl>(Dcl)))
1853 return false;
1854 if (!VD->getType()->isDependentType() &&
1855 !VD->hasInit() && !VD->isCXXForRangeDecl()) {
1856 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1857 SemaRef.Diag(
1858 VD->getLocation(),
1859 SemaRef.getLangOpts().CPlusPlus2a
1860 ? diag::warn_cxx17_compat_constexpr_local_var_no_init
1861 : diag::ext_constexpr_local_var_no_init)
1862 << isa<CXXConstructorDecl>(Dcl);
1863 } else if (!SemaRef.getLangOpts().CPlusPlus2a) {
1864 return false;
1865 }
1866 continue;
1867 }
1868 }
1869 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1870 SemaRef.Diag(VD->getLocation(),
1871 SemaRef.getLangOpts().CPlusPlus14
1872 ? diag::warn_cxx11_compat_constexpr_local_var
1873 : diag::ext_constexpr_local_var)
1874 << isa<CXXConstructorDecl>(Dcl);
1875 } else if (!SemaRef.getLangOpts().CPlusPlus14) {
1876 return false;
1877 }
1878 continue;
1879 }
1880
1881 case Decl::NamespaceAlias:
1882 case Decl::Function:
1883 // These are disallowed in C++11 and permitted in C++1y. Allow them
1884 // everywhere as an extension.
1885 if (!Cxx1yLoc.isValid())
1886 Cxx1yLoc = DS->getBeginLoc();
1887 continue;
1888
1889 default:
1890 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1891 SemaRef.Diag(DS->getBeginLoc(), diag::err_constexpr_body_invalid_stmt)
1892 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
1893 }
1894 return false;
1895 }
1896 }
1897
1898 return true;
1899}
1900
1901/// Check that the given field is initialized within a constexpr constructor.
1902///
1903/// \param Dcl The constexpr constructor being checked.
1904/// \param Field The field being checked. This may be a member of an anonymous
1905/// struct or union nested within the class being checked.
1906/// \param Inits All declarations, including anonymous struct/union members and
1907/// indirect members, for which any initialization was provided.
1908/// \param Diagnosed Whether we've emitted the error message yet. Used to attach
1909/// multiple notes for different members to the same error.
1910/// \param Kind Whether we're diagnosing a constructor as written or determining
1911/// whether the formal requirements are satisfied.
1912/// \return \c false if we're checking for validity and the constructor does
1913/// not satisfy the requirements on a constexpr constructor.
1914static bool CheckConstexprCtorInitializer(Sema &SemaRef,
1915 const FunctionDecl *Dcl,
1916 FieldDecl *Field,
1917 llvm::SmallSet<Decl*, 16> &Inits,
1918 bool &Diagnosed,
1919 Sema::CheckConstexprKind Kind) {
1920 // In C++20 onwards, there's nothing to check for validity.
1921 if (Kind == Sema::CheckConstexprKind::CheckValid &&
1922 SemaRef.getLangOpts().CPlusPlus2a)
1923 return true;
1924
1925 if (Field->isInvalidDecl())
1926 return true;
1927
1928 if (Field->isUnnamedBitfield())
1929 return true;
1930
1931 // Anonymous unions with no variant members and empty anonymous structs do not
1932 // need to be explicitly initialized. FIXME: Anonymous structs that contain no
1933 // indirect fields don't need initializing.
1934 if (Field->isAnonymousStructOrUnion() &&
1935 (Field->getType()->isUnionType()
1936 ? !Field->getType()->getAsCXXRecordDecl()->hasVariantMembers()
1937 : Field->getType()->getAsCXXRecordDecl()->isEmpty()))
1938 return true;
1939
1940 if (!Inits.count(Field)) {
1941 if (Kind == Sema::CheckConstexprKind::Diagnose) {
1942 if (!Diagnosed) {
1943 SemaRef.Diag(Dcl->getLocation(),
1944 SemaRef.getLangOpts().CPlusPlus2a
1945 ? diag::warn_cxx17_compat_constexpr_ctor_missing_init
1946 : diag::ext_constexpr_ctor_missing_init);
1947 Diagnosed = true;
1948 }
1949 SemaRef.Diag(Field->getLocation(),
1950 diag::note_constexpr_ctor_missing_init);
1951 } else if (!SemaRef.getLangOpts().CPlusPlus2a) {
1952 return false;
1953 }
1954 } else if (Field->isAnonymousStructOrUnion()) {
1955 const RecordDecl *RD = Field->getType()->castAs<RecordType>()->getDecl();
1956 for (auto *I : RD->fields())
1957 // If an anonymous union contains an anonymous struct of which any member
1958 // is initialized, all members must be initialized.
1959 if (!RD->isUnion() || Inits.count(I))
1960 if (!CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed,
1961 Kind))
1962 return false;
1963 }
1964 return true;
1965}
1966
1967/// Check the provided statement is allowed in a constexpr function
1968/// definition.
1969static bool
1970CheckConstexprFunctionStmt(Sema &SemaRef, const FunctionDecl *Dcl, Stmt *S,
1971 SmallVectorImpl<SourceLocation> &ReturnStmts,
1972 SourceLocation &Cxx1yLoc, SourceLocation &Cxx2aLoc,
1973 Sema::CheckConstexprKind Kind) {
1974 // - its function-body shall be [...] a compound-statement that contains only
1975 switch (S->getStmtClass()) {
1976 case Stmt::NullStmtClass:
1977 // - null statements,
1978 return true;
1979
1980 case Stmt::DeclStmtClass:
1981 // - static_assert-declarations
1982 // - using-declarations,
1983 // - using-directives,
1984 // - typedef declarations and alias-declarations that do not define
1985 // classes or enumerations,
1986 if (!CheckConstexprDeclStmt(SemaRef, Dcl, cast<DeclStmt>(S), Cxx1yLoc, Kind))
1987 return false;
1988 return true;
1989
1990 case Stmt::ReturnStmtClass:
1991 // - and exactly one return statement;
1992 if (isa<CXXConstructorDecl>(Dcl)) {
1993 // C++1y allows return statements in constexpr constructors.
1994 if (!Cxx1yLoc.isValid())
1995 Cxx1yLoc = S->getBeginLoc();
1996 return true;
1997 }
1998
1999 ReturnStmts.push_back(S->getBeginLoc());
2000 return true;
2001
2002 case Stmt::CompoundStmtClass: {
2003 // C++1y allows compound-statements.
2004 if (!Cxx1yLoc.isValid())
2005 Cxx1yLoc = S->getBeginLoc();
2006
2007 CompoundStmt *CompStmt = cast<CompoundStmt>(S);
2008 for (auto *BodyIt : CompStmt->body()) {
2009 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, BodyIt, ReturnStmts,
2010 Cxx1yLoc, Cxx2aLoc, Kind))
2011 return false;
2012 }
2013 return true;
2014 }
2015
2016 case Stmt::AttributedStmtClass:
2017 if (!Cxx1yLoc.isValid())
2018 Cxx1yLoc = S->getBeginLoc();
2019 return true;
2020
2021 case Stmt::IfStmtClass: {
2022 // C++1y allows if-statements.
2023 if (!Cxx1yLoc.isValid())
2024 Cxx1yLoc = S->getBeginLoc();
2025
2026 IfStmt *If = cast<IfStmt>(S);
2027 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, If->getThen(), ReturnStmts,
2028 Cxx1yLoc, Cxx2aLoc, Kind))
2029 return false;
2030 if (If->getElse() &&
2031 !CheckConstexprFunctionStmt(SemaRef, Dcl, If->getElse(), ReturnStmts,
2032 Cxx1yLoc, Cxx2aLoc, Kind))
2033 return false;
2034 return true;
2035 }
2036
2037 case Stmt::WhileStmtClass:
2038 case Stmt::DoStmtClass:
2039 case Stmt::ForStmtClass:
2040 case Stmt::CXXForRangeStmtClass:
2041 case Stmt::ContinueStmtClass:
2042 // C++1y allows all of these. We don't allow them as extensions in C++11,
2043 // because they don't make sense without variable mutation.
2044 if (!SemaRef.getLangOpts().CPlusPlus14)
2045 break;
2046 if (!Cxx1yLoc.isValid())
2047 Cxx1yLoc = S->getBeginLoc();
2048 for (Stmt *SubStmt : S->children())
2049 if (SubStmt &&
2050 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2051 Cxx1yLoc, Cxx2aLoc, Kind))
2052 return false;
2053 return true;
2054
2055 case Stmt::SwitchStmtClass:
2056 case Stmt::CaseStmtClass:
2057 case Stmt::DefaultStmtClass:
2058 case Stmt::BreakStmtClass:
2059 // C++1y allows switch-statements, and since they don't need variable
2060 // mutation, we can reasonably allow them in C++11 as an extension.
2061 if (!Cxx1yLoc.isValid())
2062 Cxx1yLoc = S->getBeginLoc();
2063 for (Stmt *SubStmt : S->children())
2064 if (SubStmt &&
2065 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2066 Cxx1yLoc, Cxx2aLoc, Kind))
2067 return false;
2068 return true;
2069
2070 case Stmt::GCCAsmStmtClass:
2071 case Stmt::MSAsmStmtClass:
2072 // C++2a allows inline assembly statements.
2073 case Stmt::CXXTryStmtClass:
2074 if (Cxx2aLoc.isInvalid())
2075 Cxx2aLoc = S->getBeginLoc();
2076 for (Stmt *SubStmt : S->children()) {
2077 if (SubStmt &&
2078 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2079 Cxx1yLoc, Cxx2aLoc, Kind))
2080 return false;
2081 }
2082 return true;
2083
2084 case Stmt::CXXCatchStmtClass:
2085 // Do not bother checking the language mode (already covered by the
2086 // try block check).
2087 if (!CheckConstexprFunctionStmt(SemaRef, Dcl,
2088 cast<CXXCatchStmt>(S)->getHandlerBlock(),
2089 ReturnStmts, Cxx1yLoc, Cxx2aLoc, Kind))
2090 return false;
2091 return true;
2092
2093 default:
2094 if (!isa<Expr>(S))
2095 break;
2096
2097 // C++1y allows expression-statements.
2098 if (!Cxx1yLoc.isValid())
2099 Cxx1yLoc = S->getBeginLoc();
2100 return true;
2101 }
2102
2103 if (Kind == Sema::CheckConstexprKind::Diagnose) {
2104 SemaRef.Diag(S->getBeginLoc(), diag::err_constexpr_body_invalid_stmt)
2105 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
2106 }
2107 return false;
2108}
2109
2110/// Check the body for the given constexpr function declaration only contains
2111/// the permitted types of statement. C++11 [dcl.constexpr]p3,p4.
2112///
2113/// \return true if the body is OK, false if we have found or diagnosed a
2114/// problem.
2115static bool CheckConstexprFunctionBody(Sema &SemaRef, const FunctionDecl *Dcl,
2116 Stmt *Body,
2117 Sema::CheckConstexprKind Kind) {
2118 SmallVector<SourceLocation, 4> ReturnStmts;
2119
2120 if (isa<CXXTryStmt>(Body)) {
2121 // C++11 [dcl.constexpr]p3:
2122 // The definition of a constexpr function shall satisfy the following
2123 // constraints: [...]
2124 // - its function-body shall be = delete, = default, or a
2125 // compound-statement
2126 //
2127 // C++11 [dcl.constexpr]p4:
2128 // In the definition of a constexpr constructor, [...]
2129 // - its function-body shall not be a function-try-block;
2130 //
2131 // This restriction is lifted in C++2a, as long as inner statements also
2132 // apply the general constexpr rules.
2133 switch (Kind) {
2134 case Sema::CheckConstexprKind::CheckValid:
2135 if (!SemaRef.getLangOpts().CPlusPlus2a)
2136 return false;
2137 break;
2138
2139 case Sema::CheckConstexprKind::Diagnose:
2140 SemaRef.Diag(Body->getBeginLoc(),
2141 !SemaRef.getLangOpts().CPlusPlus2a
2142 ? diag::ext_constexpr_function_try_block_cxx2a
2143 : diag::warn_cxx17_compat_constexpr_function_try_block)
2144 << isa<CXXConstructorDecl>(Dcl);
2145 break;
2146 }
2147 }
2148
2149 // - its function-body shall be [...] a compound-statement that contains only
2150 // [... list of cases ...]
2151 //
2152 // Note that walking the children here is enough to properly check for
2153 // CompoundStmt and CXXTryStmt body.
2154 SourceLocation Cxx1yLoc, Cxx2aLoc;
2155 for (Stmt *SubStmt : Body->children()) {
2156 if (SubStmt &&
2157 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
2158 Cxx1yLoc, Cxx2aLoc, Kind))
2159 return false;
2160 }
2161
2162 if (Kind == Sema::CheckConstexprKind::CheckValid) {
2163 // If this is only valid as an extension, report that we don't satisfy the
2164 // constraints of the current language.
2165 if ((Cxx2aLoc.isValid() && !SemaRef.getLangOpts().CPlusPlus2a) ||
2166 (Cxx1yLoc.isValid() && !SemaRef.getLangOpts().CPlusPlus17))
2167 return false;
2168 } else if (Cxx2aLoc.isValid()) {
2169 SemaRef.Diag(Cxx2aLoc,
2170 SemaRef.getLangOpts().CPlusPlus2a
2171 ? diag::warn_cxx17_compat_constexpr_body_invalid_stmt
2172 : diag::ext_constexpr_body_invalid_stmt_cxx2a)
2173 << isa<CXXConstructorDecl>(Dcl);
2174 } else if (Cxx1yLoc.isValid()) {
2175 SemaRef.Diag(Cxx1yLoc,
2176 SemaRef.getLangOpts().CPlusPlus14
2177 ? diag::warn_cxx11_compat_constexpr_body_invalid_stmt
2178 : diag::ext_constexpr_body_invalid_stmt)
2179 << isa<CXXConstructorDecl>(Dcl);
2180 }
2181
2182 if (const CXXConstructorDecl *Constructor
2183 = dyn_cast<CXXConstructorDecl>(Dcl)) {
2184 const CXXRecordDecl *RD = Constructor->getParent();
2185 // DR1359:
2186 // - every non-variant non-static data member and base class sub-object
2187 // shall be initialized;
2188 // DR1460:
2189 // - if the class is a union having variant members, exactly one of them
2190 // shall be initialized;
2191 if (RD->isUnion()) {
2192 if (Constructor->getNumCtorInitializers() == 0 &&
2193 RD->hasVariantMembers()) {
2194 if (Kind == Sema::CheckConstexprKind::Diagnose) {
2195 SemaRef.Diag(
2196 Dcl->getLocation(),
2197 SemaRef.getLangOpts().CPlusPlus2a
2198 ? diag::warn_cxx17_compat_constexpr_union_ctor_no_init
2199 : diag::ext_constexpr_union_ctor_no_init);
2200 } else if (!SemaRef.getLangOpts().CPlusPlus2a) {
2201 return false;
2202 }
2203 }
2204 } else if (!Constructor->isDependentContext() &&
2205 !Constructor->isDelegatingConstructor()) {
2206 assert(RD->getNumVBases() == 0 && "constexpr ctor with virtual bases")((RD->getNumVBases() == 0 && "constexpr ctor with virtual bases"
) ? static_cast<void> (0) : __assert_fail ("RD->getNumVBases() == 0 && \"constexpr ctor with virtual bases\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2206, __PRETTY_FUNCTION__))
;
2207
2208 // Skip detailed checking if we have enough initializers, and we would
2209 // allow at most one initializer per member.
2210 bool AnyAnonStructUnionMembers = false;
2211 unsigned Fields = 0;
2212 for (CXXRecordDecl::field_iterator I = RD->field_begin(),
2213 E = RD->field_end(); I != E; ++I, ++Fields) {
2214 if (I->isAnonymousStructOrUnion()) {
2215 AnyAnonStructUnionMembers = true;
2216 break;
2217 }
2218 }
2219 // DR1460:
2220 // - if the class is a union-like class, but is not a union, for each of
2221 // its anonymous union members having variant members, exactly one of
2222 // them shall be initialized;
2223 if (AnyAnonStructUnionMembers ||
2224 Constructor->getNumCtorInitializers() != RD->getNumBases() + Fields) {
2225 // Check initialization of non-static data members. Base classes are
2226 // always initialized so do not need to be checked. Dependent bases
2227 // might not have initializers in the member initializer list.
2228 llvm::SmallSet<Decl*, 16> Inits;
2229 for (const auto *I: Constructor->inits()) {
2230 if (FieldDecl *FD = I->getMember())
2231 Inits.insert(FD);
2232 else if (IndirectFieldDecl *ID = I->getIndirectMember())
2233 Inits.insert(ID->chain_begin(), ID->chain_end());
2234 }
2235
2236 bool Diagnosed = false;
2237 for (auto *I : RD->fields())
2238 if (!CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed,
2239 Kind))
2240 return false;
2241 }
2242 }
2243 } else {
2244 if (ReturnStmts.empty()) {
2245 // C++1y doesn't require constexpr functions to contain a 'return'
2246 // statement. We still do, unless the return type might be void, because
2247 // otherwise if there's no return statement, the function cannot
2248 // be used in a core constant expression.
2249 bool OK = SemaRef.getLangOpts().CPlusPlus14 &&
2250 (Dcl->getReturnType()->isVoidType() ||
2251 Dcl->getReturnType()->isDependentType());
2252 switch (Kind) {
2253 case Sema::CheckConstexprKind::Diagnose:
2254 SemaRef.Diag(Dcl->getLocation(),
2255 OK ? diag::warn_cxx11_compat_constexpr_body_no_return
2256 : diag::err_constexpr_body_no_return)
2257 << Dcl->isConsteval();
2258 if (!OK)
2259 return false;
2260 break;
2261
2262 case Sema::CheckConstexprKind::CheckValid:
2263 // The formal requirements don't include this rule in C++14, even
2264 // though the "must be able to produce a constant expression" rules
2265 // still imply it in some cases.
2266 if (!SemaRef.getLangOpts().CPlusPlus14)
2267 return false;
2268 break;
2269 }
2270 } else if (ReturnStmts.size() > 1) {
2271 switch (Kind) {
2272 case Sema::CheckConstexprKind::Diagnose:
2273 SemaRef.Diag(
2274 ReturnStmts.back(),
2275 SemaRef.getLangOpts().CPlusPlus14
2276 ? diag::warn_cxx11_compat_constexpr_body_multiple_return
2277 : diag::ext_constexpr_body_multiple_return);
2278 for (unsigned I = 0; I < ReturnStmts.size() - 1; ++I)
2279 SemaRef.Diag(ReturnStmts[I],
2280 diag::note_constexpr_body_previous_return);
2281 break;
2282
2283 case Sema::CheckConstexprKind::CheckValid:
2284 if (!SemaRef.getLangOpts().CPlusPlus14)
2285 return false;
2286 break;
2287 }
2288 }
2289 }
2290
2291 // C++11 [dcl.constexpr]p5:
2292 // if no function argument values exist such that the function invocation
2293 // substitution would produce a constant expression, the program is
2294 // ill-formed; no diagnostic required.
2295 // C++11 [dcl.constexpr]p3:
2296 // - every constructor call and implicit conversion used in initializing the
2297 // return value shall be one of those allowed in a constant expression.
2298 // C++11 [dcl.constexpr]p4:
2299 // - every constructor involved in initializing non-static data members and
2300 // base class sub-objects shall be a constexpr constructor.
2301 //
2302 // Note that this rule is distinct from the "requirements for a constexpr
2303 // function", so is not checked in CheckValid mode.
2304 SmallVector<PartialDiagnosticAt, 8> Diags;
2305 if (Kind == Sema::CheckConstexprKind::Diagnose &&
2306 !Expr::isPotentialConstantExpr(Dcl, Diags)) {
2307 SemaRef.Diag(Dcl->getLocation(),
2308 diag::ext_constexpr_function_never_constant_expr)
2309 << isa<CXXConstructorDecl>(Dcl) << Dcl->isConsteval();
2310 for (size_t I = 0, N = Diags.size(); I != N; ++I)
2311 SemaRef.Diag(Diags[I].first, Diags[I].second);
2312 // Don't return false here: we allow this for compatibility in
2313 // system headers.
2314 }
2315
2316 return true;
2317}
2318
2319/// Get the class that is directly named by the current context. This is the
2320/// class for which an unqualified-id in this scope could name a constructor
2321/// or destructor.
2322///
2323/// If the scope specifier denotes a class, this will be that class.
2324/// If the scope specifier is empty, this will be the class whose
2325/// member-specification we are currently within. Otherwise, there
2326/// is no such class.
2327CXXRecordDecl *Sema::getCurrentClass(Scope *, const CXXScopeSpec *SS) {
2328 assert(getLangOpts().CPlusPlus && "No class names in C!")((getLangOpts().CPlusPlus && "No class names in C!") ?
static_cast<void> (0) : __assert_fail ("getLangOpts().CPlusPlus && \"No class names in C!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2328, __PRETTY_FUNCTION__))
;
2329
2330 if (SS && SS->isInvalid())
2331 return nullptr;
2332
2333 if (SS && SS->isNotEmpty()) {
2334 DeclContext *DC = computeDeclContext(*SS, true);
2335 return dyn_cast_or_null<CXXRecordDecl>(DC);
2336 }
2337
2338 return dyn_cast_or_null<CXXRecordDecl>(CurContext);
2339}
2340
2341/// isCurrentClassName - Determine whether the identifier II is the
2342/// name of the class type currently being defined. In the case of
2343/// nested classes, this will only return true if II is the name of
2344/// the innermost class.
2345bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *S,
2346 const CXXScopeSpec *SS) {
2347 CXXRecordDecl *CurDecl = getCurrentClass(S, SS);
2348 return CurDecl && &II == CurDecl->getIdentifier();
2349}
2350
2351/// Determine whether the identifier II is a typo for the name of
2352/// the class type currently being defined. If so, update it to the identifier
2353/// that should have been used.
2354bool Sema::isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS) {
2355 assert(getLangOpts().CPlusPlus && "No class names in C!")((getLangOpts().CPlusPlus && "No class names in C!") ?
static_cast<void> (0) : __assert_fail ("getLangOpts().CPlusPlus && \"No class names in C!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2355, __PRETTY_FUNCTION__))
;
2356
2357 if (!getLangOpts().SpellChecking)
2358 return false;
2359
2360 CXXRecordDecl *CurDecl;
2361 if (SS && SS->isSet() && !SS->isInvalid()) {
2362 DeclContext *DC = computeDeclContext(*SS, true);
2363 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
2364 } else
2365 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
2366
2367 if (CurDecl && CurDecl->getIdentifier() && II != CurDecl->getIdentifier() &&
2368 3 * II->getName().edit_distance(CurDecl->getIdentifier()->getName())
2369 < II->getLength()) {
2370 II = CurDecl->getIdentifier();
2371 return true;
2372 }
2373
2374 return false;
2375}
2376
2377/// Determine whether the given class is a base class of the given
2378/// class, including looking at dependent bases.
2379static bool findCircularInheritance(const CXXRecordDecl *Class,
2380 const CXXRecordDecl *Current) {
2381 SmallVector<const CXXRecordDecl*, 8> Queue;
2382
2383 Class = Class->getCanonicalDecl();
2384 while (true) {
2385 for (const auto &I : Current->bases()) {
2386 CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
2387 if (!Base)
2388 continue;
2389
2390 Base = Base->getDefinition();
2391 if (!Base)
2392 continue;
2393
2394 if (Base->getCanonicalDecl() == Class)
2395 return true;
2396
2397 Queue.push_back(Base);
2398 }
2399
2400 if (Queue.empty())
2401 return false;
2402
2403 Current = Queue.pop_back_val();
2404 }
2405
2406 return false;
2407}
2408
2409/// Check the validity of a C++ base class specifier.
2410///
2411/// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics
2412/// and returns NULL otherwise.
2413CXXBaseSpecifier *
2414Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
2415 SourceRange SpecifierRange,
2416 bool Virtual, AccessSpecifier Access,
2417 TypeSourceInfo *TInfo,
2418 SourceLocation EllipsisLoc) {
2419 QualType BaseType = TInfo->getType();
2420
2421 // C++ [class.union]p1:
2422 // A union shall not have base classes.
2423 if (Class->isUnion()) {
2424 Diag(Class->getLocation(), diag::err_base_clause_on_union)
2425 << SpecifierRange;
2426 return nullptr;
2427 }
2428
2429 if (EllipsisLoc.isValid() &&
2430 !TInfo->getType()->containsUnexpandedParameterPack()) {
2431 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
2432 << TInfo->getTypeLoc().getSourceRange();
2433 EllipsisLoc = SourceLocation();
2434 }
2435
2436 SourceLocation BaseLoc = TInfo->getTypeLoc().getBeginLoc();
2437
2438 if (BaseType->isDependentType()) {
2439 // Make sure that we don't have circular inheritance among our dependent
2440 // bases. For non-dependent bases, the check for completeness below handles
2441 // this.
2442 if (CXXRecordDecl *BaseDecl = BaseType->getAsCXXRecordDecl()) {
2443 if (BaseDecl->getCanonicalDecl() == Class->getCanonicalDecl() ||
2444 ((BaseDecl = BaseDecl->getDefinition()) &&
2445 findCircularInheritance(Class, BaseDecl))) {
2446 Diag(BaseLoc, diag::err_circular_inheritance)
2447 << BaseType << Context.getTypeDeclType(Class);
2448
2449 if (BaseDecl->getCanonicalDecl() != Class->getCanonicalDecl())
2450 Diag(BaseDecl->getLocation(), diag::note_previous_decl)
2451 << BaseType;
2452
2453 return nullptr;
2454 }
2455 }
2456
2457 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2458 Class->getTagKind() == TTK_Class,
2459 Access, TInfo, EllipsisLoc);
2460 }
2461
2462 // Base specifiers must be record types.
2463 if (!BaseType->isRecordType()) {
2464 Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange;
2465 return nullptr;
2466 }
2467
2468 // C++ [class.union]p1:
2469 // A union shall not be used as a base class.
2470 if (BaseType->isUnionType()) {
2471 Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange;
2472 return nullptr;
2473 }
2474
2475 // For the MS ABI, propagate DLL attributes to base class templates.
2476 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2477 if (Attr *ClassAttr = getDLLAttr(Class)) {
2478 if (auto *BaseTemplate = dyn_cast_or_null<ClassTemplateSpecializationDecl>(
2479 BaseType->getAsCXXRecordDecl())) {
2480 propagateDLLAttrToBaseClassTemplate(Class, ClassAttr, BaseTemplate,
2481 BaseLoc);
2482 }
2483 }
2484 }
2485
2486 // C++ [class.derived]p2:
2487 // The class-name in a base-specifier shall not be an incompletely
2488 // defined class.
2489 if (RequireCompleteType(BaseLoc, BaseType,
2490 diag::err_incomplete_base_class, SpecifierRange)) {
2491 Class->setInvalidDecl();
2492 return nullptr;
2493 }
2494
2495 // If the base class is polymorphic or isn't empty, the new one is/isn't, too.
2496 RecordDecl *BaseDecl = BaseType->castAs<RecordType>()->getDecl();
2497 assert(BaseDecl && "Record type has no declaration")((BaseDecl && "Record type has no declaration") ? static_cast
<void> (0) : __assert_fail ("BaseDecl && \"Record type has no declaration\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2497, __PRETTY_FUNCTION__))
;
2498 BaseDecl = BaseDecl->getDefinition();
2499 assert(BaseDecl && "Base type is not incomplete, but has no definition")((BaseDecl && "Base type is not incomplete, but has no definition"
) ? static_cast<void> (0) : __assert_fail ("BaseDecl && \"Base type is not incomplete, but has no definition\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2499, __PRETTY_FUNCTION__))
;
2500 CXXRecordDecl *CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
2501 assert(CXXBaseDecl && "Base type is not a C++ type")((CXXBaseDecl && "Base type is not a C++ type") ? static_cast
<void> (0) : __assert_fail ("CXXBaseDecl && \"Base type is not a C++ type\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2501, __PRETTY_FUNCTION__))
;
2502
2503 // Microsoft docs say:
2504 // "If a base-class has a code_seg attribute, derived classes must have the
2505 // same attribute."
2506 const auto *BaseCSA = CXXBaseDecl->getAttr<CodeSegAttr>();
2507 const auto *DerivedCSA = Class->getAttr<CodeSegAttr>();
2508 if ((DerivedCSA || BaseCSA) &&
2509 (!BaseCSA || !DerivedCSA || BaseCSA->getName() != DerivedCSA->getName())) {
2510 Diag(Class->getLocation(), diag::err_mismatched_code_seg_base);
2511 Diag(CXXBaseDecl->getLocation(), diag::note_base_class_specified_here)
2512 << CXXBaseDecl;
2513 return nullptr;
2514 }
2515
2516 // A class which contains a flexible array member is not suitable for use as a
2517 // base class:
2518 // - If the layout determines that a base comes before another base,
2519 // the flexible array member would index into the subsequent base.
2520 // - If the layout determines that base comes before the derived class,
2521 // the flexible array member would index into the derived class.
2522 if (CXXBaseDecl->hasFlexibleArrayMember()) {
2523 Diag(BaseLoc, diag::err_base_class_has_flexible_array_member)
2524 << CXXBaseDecl->getDeclName();
2525 return nullptr;
2526 }
2527
2528 // C++ [class]p3:
2529 // If a class is marked final and it appears as a base-type-specifier in
2530 // base-clause, the program is ill-formed.
2531 if (FinalAttr *FA = CXXBaseDecl->getAttr<FinalAttr>()) {
2532 Diag(BaseLoc, diag::err_class_marked_final_used_as_base)
2533 << CXXBaseDecl->getDeclName()
2534 << FA->isSpelledAsSealed();
2535 Diag(CXXBaseDecl->getLocation(), diag::note_entity_declared_at)
2536 << CXXBaseDecl->getDeclName() << FA->getRange();
2537 return nullptr;
2538 }
2539
2540 if (BaseDecl->isInvalidDecl())
2541 Class->setInvalidDecl();
2542
2543 // Create the base specifier.
2544 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2545 Class->getTagKind() == TTK_Class,
2546 Access, TInfo, EllipsisLoc);
2547}
2548
2549/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is
2550/// one entry in the base class list of a class specifier, for
2551/// example:
2552/// class foo : public bar, virtual private baz {
2553/// 'public bar' and 'virtual private baz' are each base-specifiers.
2554BaseResult
2555Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
2556 ParsedAttributes &Attributes,
2557 bool Virtual, AccessSpecifier Access,
2558 ParsedType basetype, SourceLocation BaseLoc,
2559 SourceLocation EllipsisLoc) {
2560 if (!classdecl)
2561 return true;
2562
2563 AdjustDeclIfTemplate(classdecl);
2564 CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(classdecl);
2565 if (!Class)
2566 return true;
2567
2568 // We haven't yet attached the base specifiers.
2569 Class->setIsParsingBaseSpecifiers();
2570
2571 // We do not support any C++11 attributes on base-specifiers yet.
2572 // Diagnose any attributes we see.
2573 for (const ParsedAttr &AL : Attributes) {
2574 if (AL.isInvalid() || AL.getKind() == ParsedAttr::IgnoredAttribute)
2575 continue;
2576 Diag(AL.getLoc(), AL.getKind() == ParsedAttr::UnknownAttribute
2577 ? (unsigned)diag::warn_unknown_attribute_ignored
2578 : (unsigned)diag::err_base_specifier_attribute)
2579 << AL;
2580 }
2581
2582 TypeSourceInfo *TInfo = nullptr;
2583 GetTypeFromParser(basetype, &TInfo);
2584
2585 if (EllipsisLoc.isInvalid() &&
2586 DiagnoseUnexpandedParameterPack(SpecifierRange.getBegin(), TInfo,
2587 UPPC_BaseType))
2588 return true;
2589
2590 if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange,
2591 Virtual, Access, TInfo,
2592 EllipsisLoc))
2593 return BaseSpec;
2594 else
2595 Class->setInvalidDecl();
2596
2597 return true;
2598}
2599
2600/// Use small set to collect indirect bases. As this is only used
2601/// locally, there's no need to abstract the small size parameter.
2602typedef llvm::SmallPtrSet<QualType, 4> IndirectBaseSet;
2603
2604/// Recursively add the bases of Type. Don't add Type itself.
2605static void
2606NoteIndirectBases(ASTContext &Context, IndirectBaseSet &Set,
2607 const QualType &Type)
2608{
2609 // Even though the incoming type is a base, it might not be
2610 // a class -- it could be a template parm, for instance.
2611 if (auto Rec = Type->getAs<RecordType>()) {
2612 auto Decl = Rec->getAsCXXRecordDecl();
2613
2614 // Iterate over its bases.
2615 for (const auto &BaseSpec : Decl->bases()) {
2616 QualType Base = Context.getCanonicalType(BaseSpec.getType())
2617 .getUnqualifiedType();
2618 if (Set.insert(Base).second)
2619 // If we've not already seen it, recurse.
2620 NoteIndirectBases(Context, Set, Base);
2621 }
2622 }
2623}
2624
2625/// Performs the actual work of attaching the given base class
2626/// specifiers to a C++ class.
2627bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class,
2628 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2629 if (Bases.empty())
2630 return false;
2631
2632 // Used to keep track of which base types we have already seen, so
2633 // that we can properly diagnose redundant direct base types. Note
2634 // that the key is always the unqualified canonical type of the base
2635 // class.
2636 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes;
2637
2638 // Used to track indirect bases so we can see if a direct base is
2639 // ambiguous.
2640 IndirectBaseSet IndirectBaseTypes;
2641
2642 // Copy non-redundant base specifiers into permanent storage.
2643 unsigned NumGoodBases = 0;
2644 bool Invalid = false;
2645 for (unsigned idx = 0; idx < Bases.size(); ++idx) {
2646 QualType NewBaseType
2647 = Context.getCanonicalType(Bases[idx]->getType());
2648 NewBaseType = NewBaseType.getLocalUnqualifiedType();
2649
2650 CXXBaseSpecifier *&KnownBase = KnownBaseTypes[NewBaseType];
2651 if (KnownBase) {
2652 // C++ [class.mi]p3:
2653 // A class shall not be specified as a direct base class of a
2654 // derived class more than once.
2655 Diag(Bases[idx]->getBeginLoc(), diag::err_duplicate_base_class)
2656 << KnownBase->getType() << Bases[idx]->getSourceRange();
2657
2658 // Delete the duplicate base class specifier; we're going to
2659 // overwrite its pointer later.
2660 Context.Deallocate(Bases[idx]);
2661
2662 Invalid = true;
2663 } else {
2664 // Okay, add this new base class.
2665 KnownBase = Bases[idx];
2666 Bases[NumGoodBases++] = Bases[idx];
2667
2668 // Note this base's direct & indirect bases, if there could be ambiguity.
2669 if (Bases.size() > 1)
2670 NoteIndirectBases(Context, IndirectBaseTypes, NewBaseType);
2671
2672 if (const RecordType *Record = NewBaseType->getAs<RecordType>()) {
2673 const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
2674 if (Class->isInterface() &&
2675 (!RD->isInterfaceLike() ||
2676 KnownBase->getAccessSpecifier() != AS_public)) {
2677 // The Microsoft extension __interface does not permit bases that
2678 // are not themselves public interfaces.
2679 Diag(KnownBase->getBeginLoc(), diag::err_invalid_base_in_interface)
2680 << getRecordDiagFromTagKind(RD->getTagKind()) << RD
2681 << RD->getSourceRange();
2682 Invalid = true;
2683 }
2684 if (RD->hasAttr<WeakAttr>())
2685 Class->addAttr(WeakAttr::CreateImplicit(Context));
2686 }
2687 }
2688 }
2689
2690 // Attach the remaining base class specifiers to the derived class.
2691 Class->setBases(Bases.data(), NumGoodBases);
2692
2693 // Check that the only base classes that are duplicate are virtual.
2694 for (unsigned idx = 0; idx < NumGoodBases; ++idx) {
2695 // Check whether this direct base is inaccessible due to ambiguity.
2696 QualType BaseType = Bases[idx]->getType();
2697
2698 // Skip all dependent types in templates being used as base specifiers.
2699 // Checks below assume that the base specifier is a CXXRecord.
2700 if (BaseType->isDependentType())
2701 continue;
2702
2703 CanQualType CanonicalBase = Context.getCanonicalType(BaseType)
2704 .getUnqualifiedType();
2705
2706 if (IndirectBaseTypes.count(CanonicalBase)) {
2707 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2708 /*DetectVirtual=*/true);
2709 bool found
2710 = Class->isDerivedFrom(CanonicalBase->getAsCXXRecordDecl(), Paths);
2711 assert(found)((found) ? static_cast<void> (0) : __assert_fail ("found"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2711, __PRETTY_FUNCTION__))
;
2712 (void)found;
2713
2714 if (Paths.isAmbiguous(CanonicalBase))
2715 Diag(Bases[idx]->getBeginLoc(), diag::warn_inaccessible_base_class)
2716 << BaseType << getAmbiguousPathsDisplayString(Paths)
2717 << Bases[idx]->getSourceRange();
2718 else
2719 assert(Bases[idx]->isVirtual())((Bases[idx]->isVirtual()) ? static_cast<void> (0) :
__assert_fail ("Bases[idx]->isVirtual()", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2719, __PRETTY_FUNCTION__))
;
2720 }
2721
2722 // Delete the base class specifier, since its data has been copied
2723 // into the CXXRecordDecl.
2724 Context.Deallocate(Bases[idx]);
2725 }
2726
2727 return Invalid;
2728}
2729
2730/// ActOnBaseSpecifiers - Attach the given base specifiers to the
2731/// class, after checking whether there are any duplicate base
2732/// classes.
2733void Sema::ActOnBaseSpecifiers(Decl *ClassDecl,
2734 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2735 if (!ClassDecl || Bases.empty())
2736 return;
2737
2738 AdjustDeclIfTemplate(ClassDecl);
2739 AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl), Bases);
2740}
2741
2742/// Determine whether the type \p Derived is a C++ class that is
2743/// derived from the type \p Base.
2744bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base) {
2745 if (!getLangOpts().CPlusPlus)
2746 return false;
2747
2748 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2749 if (!DerivedRD)
2750 return false;
2751
2752 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2753 if (!BaseRD)
2754 return false;
2755
2756 // If either the base or the derived type is invalid, don't try to
2757 // check whether one is derived from the other.
2758 if (BaseRD->isInvalidDecl() || DerivedRD->isInvalidDecl())
2759 return false;
2760
2761 // FIXME: In a modules build, do we need the entire path to be visible for us
2762 // to be able to use the inheritance relationship?
2763 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2764 return false;
2765
2766 return DerivedRD->isDerivedFrom(BaseRD);
2767}
2768
2769/// Determine whether the type \p Derived is a C++ class that is
2770/// derived from the type \p Base.
2771bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base,
2772 CXXBasePaths &Paths) {
2773 if (!getLangOpts().CPlusPlus)
2774 return false;
2775
2776 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2777 if (!DerivedRD)
2778 return false;
2779
2780 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2781 if (!BaseRD)
2782 return false;
2783
2784 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2785 return false;
2786
2787 return DerivedRD->isDerivedFrom(BaseRD, Paths);
2788}
2789
2790static void BuildBasePathArray(const CXXBasePath &Path,
2791 CXXCastPath &BasePathArray) {
2792 // We first go backward and check if we have a virtual base.
2793 // FIXME: It would be better if CXXBasePath had the base specifier for
2794 // the nearest virtual base.
2795 unsigned Start = 0;
2796 for (unsigned I = Path.size(); I != 0; --I) {
2797 if (Path[I - 1].Base->isVirtual()) {
2798 Start = I - 1;
2799 break;
2800 }
2801 }
2802
2803 // Now add all bases.
2804 for (unsigned I = Start, E = Path.size(); I != E; ++I)
2805 BasePathArray.push_back(const_cast<CXXBaseSpecifier*>(Path[I].Base));
2806}
2807
2808
2809void Sema::BuildBasePathArray(const CXXBasePaths &Paths,
2810 CXXCastPath &BasePathArray) {
2811 assert(BasePathArray.empty() && "Base path array must be empty!")((BasePathArray.empty() && "Base path array must be empty!"
) ? static_cast<void> (0) : __assert_fail ("BasePathArray.empty() && \"Base path array must be empty!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2811, __PRETTY_FUNCTION__))
;
2812 assert(Paths.isRecordingPaths() && "Must record paths!")((Paths.isRecordingPaths() && "Must record paths!") ?
static_cast<void> (0) : __assert_fail ("Paths.isRecordingPaths() && \"Must record paths!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2812, __PRETTY_FUNCTION__))
;
2813 return ::BuildBasePathArray(Paths.front(), BasePathArray);
2814}
2815/// CheckDerivedToBaseConversion - Check whether the Derived-to-Base
2816/// conversion (where Derived and Base are class types) is
2817/// well-formed, meaning that the conversion is unambiguous (and
2818/// that all of the base classes are accessible). Returns true
2819/// and emits a diagnostic if the code is ill-formed, returns false
2820/// otherwise. Loc is the location where this routine should point to
2821/// if there is an error, and Range is the source range to highlight
2822/// if there is an error.
2823///
2824/// If either InaccessibleBaseID or AmbigiousBaseConvID are 0, then the
2825/// diagnostic for the respective type of error will be suppressed, but the
2826/// check for ill-formed code will still be performed.
2827bool
2828Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2829 unsigned InaccessibleBaseID,
2830 unsigned AmbigiousBaseConvID,
2831 SourceLocation Loc, SourceRange Range,
2832 DeclarationName Name,
2833 CXXCastPath *BasePath,
2834 bool IgnoreAccess) {
2835 // First, determine whether the path from Derived to Base is
2836 // ambiguous. This is slightly more expensive than checking whether
2837 // the Derived to Base conversion exists, because here we need to
2838 // explore multiple paths to determine if there is an ambiguity.
2839 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2840 /*DetectVirtual=*/false);
2841 bool DerivationOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2842 if (!DerivationOkay)
2843 return true;
2844
2845 const CXXBasePath *Path = nullptr;
2846 if (!Paths.isAmbiguous(Context.getCanonicalType(Base).getUnqualifiedType()))
2847 Path = &Paths.front();
2848
2849 // For MSVC compatibility, check if Derived directly inherits from Base. Clang
2850 // warns about this hierarchy under -Winaccessible-base, but MSVC allows the
2851 // user to access such bases.
2852 if (!Path && getLangOpts().MSVCCompat) {
2853 for (const CXXBasePath &PossiblePath : Paths) {
2854 if (PossiblePath.size() == 1) {
2855 Path = &PossiblePath;
2856 if (AmbigiousBaseConvID)
2857 Diag(Loc, diag::ext_ms_ambiguous_direct_base)
2858 << Base << Derived << Range;
2859 break;
2860 }
2861 }
2862 }
2863
2864 if (Path) {
2865 if (!IgnoreAccess) {
2866 // Check that the base class can be accessed.
2867 switch (
2868 CheckBaseClassAccess(Loc, Base, Derived, *Path, InaccessibleBaseID)) {
2869 case AR_inaccessible:
2870 return true;
2871 case AR_accessible:
2872 case AR_dependent:
2873 case AR_delayed:
2874 break;
2875 }
2876 }
2877
2878 // Build a base path if necessary.
2879 if (BasePath)
2880 ::BuildBasePathArray(*Path, *BasePath);
2881 return false;
2882 }
2883
2884 if (AmbigiousBaseConvID) {
2885 // We know that the derived-to-base conversion is ambiguous, and
2886 // we're going to produce a diagnostic. Perform the derived-to-base
2887 // search just one more time to compute all of the possible paths so
2888 // that we can print them out. This is more expensive than any of
2889 // the previous derived-to-base checks we've done, but at this point
2890 // performance isn't as much of an issue.
2891 Paths.clear();
2892 Paths.setRecordingPaths(true);
2893 bool StillOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2894 assert(StillOkay && "Can only be used with a derived-to-base conversion")((StillOkay && "Can only be used with a derived-to-base conversion"
) ? static_cast<void> (0) : __assert_fail ("StillOkay && \"Can only be used with a derived-to-base conversion\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2894, __PRETTY_FUNCTION__))
;
2895 (void)StillOkay;
2896
2897 // Build up a textual representation of the ambiguous paths, e.g.,
2898 // D -> B -> A, that will be used to illustrate the ambiguous
2899 // conversions in the diagnostic. We only print one of the paths
2900 // to each base class subobject.
2901 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
2902
2903 Diag(Loc, AmbigiousBaseConvID)
2904 << Derived << Base << PathDisplayStr << Range << Name;
2905 }
2906 return true;
2907}
2908
2909bool
2910Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2911 SourceLocation Loc, SourceRange Range,
2912 CXXCastPath *BasePath,
2913 bool IgnoreAccess) {
2914 return CheckDerivedToBaseConversion(
2915 Derived, Base, diag::err_upcast_to_inaccessible_base,
2916 diag::err_ambiguous_derived_to_base_conv, Loc, Range, DeclarationName(),
2917 BasePath, IgnoreAccess);
2918}
2919
2920
2921/// Builds a string representing ambiguous paths from a
2922/// specific derived class to different subobjects of the same base
2923/// class.
2924///
2925/// This function builds a string that can be used in error messages
2926/// to show the different paths that one can take through the
2927/// inheritance hierarchy to go from the derived class to different
2928/// subobjects of a base class. The result looks something like this:
2929/// @code
2930/// struct D -> struct B -> struct A
2931/// struct D -> struct C -> struct A
2932/// @endcode
2933std::string Sema::getAmbiguousPathsDisplayString(CXXBasePaths &Paths) {
2934 std::string PathDisplayStr;
2935 std::set<unsigned> DisplayedPaths;
2936 for (CXXBasePaths::paths_iterator Path = Paths.begin();
2937 Path != Paths.end(); ++Path) {
2938 if (DisplayedPaths.insert(Path->back().SubobjectNumber).second) {
2939 // We haven't displayed a path to this particular base
2940 // class subobject yet.
2941 PathDisplayStr += "\n ";
2942 PathDisplayStr += Context.getTypeDeclType(Paths.getOrigin()).getAsString();
2943 for (CXXBasePath::const_iterator Element = Path->begin();
2944 Element != Path->end(); ++Element)
2945 PathDisplayStr += " -> " + Element->Base->getType().getAsString();
2946 }
2947 }
2948
2949 return PathDisplayStr;
2950}
2951
2952//===----------------------------------------------------------------------===//
2953// C++ class member Handling
2954//===----------------------------------------------------------------------===//
2955
2956/// ActOnAccessSpecifier - Parsed an access specifier followed by a colon.
2957bool Sema::ActOnAccessSpecifier(AccessSpecifier Access, SourceLocation ASLoc,
2958 SourceLocation ColonLoc,
2959 const ParsedAttributesView &Attrs) {
2960 assert(Access != AS_none && "Invalid kind for syntactic access specifier!")((Access != AS_none && "Invalid kind for syntactic access specifier!"
) ? static_cast<void> (0) : __assert_fail ("Access != AS_none && \"Invalid kind for syntactic access specifier!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 2960, __PRETTY_FUNCTION__))
;
2961 AccessSpecDecl *ASDecl = AccessSpecDecl::Create(Context, Access, CurContext,
2962 ASLoc, ColonLoc);
2963 CurContext->addHiddenDecl(ASDecl);
2964 return ProcessAccessDeclAttributeList(ASDecl, Attrs);
2965}
2966
2967/// CheckOverrideControl - Check C++11 override control semantics.
2968void Sema::CheckOverrideControl(NamedDecl *D) {
2969 if (D->isInvalidDecl())
2970 return;
2971
2972 // We only care about "override" and "final" declarations.
2973 if (!D->hasAttr<OverrideAttr>() && !D->hasAttr<FinalAttr>())
2974 return;
2975
2976 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
2977
2978 // We can't check dependent instance methods.
2979 if (MD && MD->isInstance() &&
2980 (MD->getParent()->hasAnyDependentBases() ||
2981 MD->getType()->isDependentType()))
2982 return;
2983
2984 if (MD && !MD->isVirtual()) {
2985 // If we have a non-virtual method, check if if hides a virtual method.
2986 // (In that case, it's most likely the method has the wrong type.)
2987 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
2988 FindHiddenVirtualMethods(MD, OverloadedMethods);
2989
2990 if (!OverloadedMethods.empty()) {
2991 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
2992 Diag(OA->getLocation(),
2993 diag::override_keyword_hides_virtual_member_function)
2994 << "override" << (OverloadedMethods.size() > 1);
2995 } else if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
2996 Diag(FA->getLocation(),
2997 diag::override_keyword_hides_virtual_member_function)
2998 << (FA->isSpelledAsSealed() ? "sealed" : "final")
2999 << (OverloadedMethods.size() > 1);
3000 }
3001 NoteHiddenVirtualMethods(MD, OverloadedMethods);
3002 MD->setInvalidDecl();
3003 return;
3004 }
3005 // Fall through into the general case diagnostic.
3006 // FIXME: We might want to attempt typo correction here.
3007 }
3008
3009 if (!MD || !MD->isVirtual()) {
3010 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
3011 Diag(OA->getLocation(),
3012 diag::override_keyword_only_allowed_on_virtual_member_functions)
3013 << "override" << FixItHint::CreateRemoval(OA->getLocation());
3014 D->dropAttr<OverrideAttr>();
3015 }
3016 if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
3017 Diag(FA->getLocation(),
3018 diag::override_keyword_only_allowed_on_virtual_member_functions)
3019 << (FA->isSpelledAsSealed() ? "sealed" : "final")
3020 << FixItHint::CreateRemoval(FA->getLocation());
3021 D->dropAttr<FinalAttr>();
3022 }
3023 return;
3024 }
3025
3026 // C++11 [class.virtual]p5:
3027 // If a function is marked with the virt-specifier override and
3028 // does not override a member function of a base class, the program is
3029 // ill-formed.
3030 bool HasOverriddenMethods = MD->size_overridden_methods() != 0;
3031 if (MD->hasAttr<OverrideAttr>() && !HasOverriddenMethods)
3032 Diag(MD->getLocation(), diag::err_function_marked_override_not_overriding)
3033 << MD->getDeclName();
3034}
3035
3036void Sema::DiagnoseAbsenceOfOverrideControl(NamedDecl *D) {
3037 if (D->isInvalidDecl() || D->hasAttr<OverrideAttr>())
3038 return;
3039 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
3040 if (!MD || MD->isImplicit() || MD->hasAttr<FinalAttr>())
3041 return;
3042
3043 SourceLocation Loc = MD->getLocation();
3044 SourceLocation SpellingLoc = Loc;
3045 if (getSourceManager().isMacroArgExpansion(Loc))
3046 SpellingLoc = getSourceManager().getImmediateExpansionRange(Loc).getBegin();
3047 SpellingLoc = getSourceManager().getSpellingLoc(SpellingLoc);
3048 if (SpellingLoc.isValid() && getSourceManager().isInSystemHeader(SpellingLoc))
3049 return;
3050
3051 if (MD->size_overridden_methods() > 0) {
3052 unsigned DiagID = isa<CXXDestructorDecl>(MD)
3053 ? diag::warn_destructor_marked_not_override_overriding
3054 : diag::warn_function_marked_not_override_overriding;
3055 Diag(MD->getLocation(), DiagID) << MD->getDeclName();
3056 const CXXMethodDecl *OMD = *MD->begin_overridden_methods();
3057 Diag(OMD->getLocation(), diag::note_overridden_virtual_function);
3058 }
3059}
3060
3061/// CheckIfOverriddenFunctionIsMarkedFinal - Checks whether a virtual member
3062/// function overrides a virtual member function marked 'final', according to
3063/// C++11 [class.virtual]p4.
3064bool Sema::CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
3065 const CXXMethodDecl *Old) {
3066 FinalAttr *FA = Old->getAttr<FinalAttr>();
3067 if (!FA)
3068 return false;
3069
3070 Diag(New->getLocation(), diag::err_final_function_overridden)
3071 << New->getDeclName()
3072 << FA->isSpelledAsSealed();
3073 Diag(Old->getLocation(), diag::note_overridden_virtual_function);
3074 return true;
3075}
3076
3077static bool InitializationHasSideEffects(const FieldDecl &FD) {
3078 const Type *T = FD.getType()->getBaseElementTypeUnsafe();
3079 // FIXME: Destruction of ObjC lifetime types has side-effects.
3080 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3081 return !RD->isCompleteDefinition() ||
3082 !RD->hasTrivialDefaultConstructor() ||
3083 !RD->hasTrivialDestructor();
3084 return false;
3085}
3086
3087static const ParsedAttr *getMSPropertyAttr(const ParsedAttributesView &list) {
3088 ParsedAttributesView::const_iterator Itr =
3089 llvm::find_if(list, [](const ParsedAttr &AL) {
3090 return AL.isDeclspecPropertyAttribute();
3091 });
3092 if (Itr != list.end())
3093 return &*Itr;
3094 return nullptr;
3095}
3096
3097// Check if there is a field shadowing.
3098void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,
3099 DeclarationName FieldName,
3100 const CXXRecordDecl *RD,
3101 bool DeclIsField) {
3102 if (Diags.isIgnored(diag::warn_shadow_field, Loc))
3103 return;
3104
3105 // To record a shadowed field in a base
3106 std::map<CXXRecordDecl*, NamedDecl*> Bases;
3107 auto FieldShadowed = [&](const CXXBaseSpecifier *Specifier,
3108 CXXBasePath &Path) {
3109 const auto Base = Specifier->getType()->getAsCXXRecordDecl();
3110 // Record an ambiguous path directly
3111 if (Bases.find(Base) != Bases.end())
3112 return true;
3113 for (const auto Field : Base->lookup(FieldName)) {
3114 if ((isa<FieldDecl>(Field) || isa<IndirectFieldDecl>(Field)) &&
3115 Field->getAccess() != AS_private) {
3116 assert(Field->getAccess() != AS_none)((Field->getAccess() != AS_none) ? static_cast<void>
(0) : __assert_fail ("Field->getAccess() != AS_none", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3116, __PRETTY_FUNCTION__))
;
3117 assert(Bases.find(Base) == Bases.end())((Bases.find(Base) == Bases.end()) ? static_cast<void> (
0) : __assert_fail ("Bases.find(Base) == Bases.end()", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3117, __PRETTY_FUNCTION__))
;
3118 Bases[Base] = Field;
3119 return true;
3120 }
3121 }
3122 return false;
3123 };
3124
3125 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
3126 /*DetectVirtual=*/true);
3127 if (!RD->lookupInBases(FieldShadowed, Paths))
3128 return;
3129
3130 for (const auto &P : Paths) {
3131 auto Base = P.back().Base->getType()->getAsCXXRecordDecl();
3132 auto It = Bases.find(Base);
3133 // Skip duplicated bases
3134 if (It == Bases.end())
3135 continue;
3136 auto BaseField = It->second;
3137 assert(BaseField->getAccess() != AS_private)((BaseField->getAccess() != AS_private) ? static_cast<void
> (0) : __assert_fail ("BaseField->getAccess() != AS_private"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3137, __PRETTY_FUNCTION__))
;
3138 if (AS_none !=
3139 CXXRecordDecl::MergeAccess(P.Access, BaseField->getAccess())) {
3140 Diag(Loc, diag::warn_shadow_field)
3141 << FieldName << RD << Base << DeclIsField;
3142 Diag(BaseField->getLocation(), diag::note_shadow_field);
3143 Bases.erase(It);
3144 }
3145 }
3146}
3147
3148/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member
3149/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the
3150/// bitfield width if there is one, 'InitExpr' specifies the initializer if
3151/// one has been parsed, and 'InitStyle' is set if an in-class initializer is
3152/// present (but parsing it has been deferred).
3153NamedDecl *
3154Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D,
3155 MultiTemplateParamsArg TemplateParameterLists,
3156 Expr *BW, const VirtSpecifiers &VS,
3157 InClassInitStyle InitStyle) {
3158 const DeclSpec &DS = D.getDeclSpec();
3159 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
3160 DeclarationName Name = NameInfo.getName();
3161 SourceLocation Loc = NameInfo.getLoc();
3162
3163 // For anonymous bitfields, the location should point to the type.
3164 if (Loc.isInvalid())
3165 Loc = D.getBeginLoc();
3166
3167 Expr *BitWidth = static_cast<Expr*>(BW);
3168
3169 assert(isa<CXXRecordDecl>(CurContext))((isa<CXXRecordDecl>(CurContext)) ? static_cast<void
> (0) : __assert_fail ("isa<CXXRecordDecl>(CurContext)"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3169, __PRETTY_FUNCTION__))
;
3170 assert(!DS.isFriendSpecified())((!DS.isFriendSpecified()) ? static_cast<void> (0) : __assert_fail
("!DS.isFriendSpecified()", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3170, __PRETTY_FUNCTION__))
;
3171
3172 bool isFunc = D.isDeclarationOfFunction();
3173 const ParsedAttr *MSPropertyAttr =
3174 getMSPropertyAttr(D.getDeclSpec().getAttributes());
3175
3176 if (cast<CXXRecordDecl>(CurContext)->isInterface()) {
3177 // The Microsoft extension __interface only permits public member functions
3178 // and prohibits constructors, destructors, operators, non-public member
3179 // functions, static methods and data members.
3180 unsigned InvalidDecl;
3181 bool ShowDeclName = true;
3182 if (!isFunc &&
3183 (DS.getStorageClassSpec() == DeclSpec::SCS_typedef || MSPropertyAttr))
3184 InvalidDecl = 0;
3185 else if (!isFunc)
3186 InvalidDecl = 1;
3187 else if (AS != AS_public)
3188 InvalidDecl = 2;
3189 else if (DS.getStorageClassSpec() == DeclSpec::SCS_static)
3190 InvalidDecl = 3;
3191 else switch (Name.getNameKind()) {
3192 case DeclarationName::CXXConstructorName:
3193 InvalidDecl = 4;
3194 ShowDeclName = false;
3195 break;
3196
3197 case DeclarationName::CXXDestructorName:
3198 InvalidDecl = 5;
3199 ShowDeclName = false;
3200 break;
3201
3202 case DeclarationName::CXXOperatorName:
3203 case DeclarationName::CXXConversionFunctionName:
3204 InvalidDecl = 6;
3205 break;
3206
3207 default:
3208 InvalidDecl = 0;
3209 break;
3210 }
3211
3212 if (InvalidDecl) {
3213 if (ShowDeclName)
3214 Diag(Loc, diag::err_invalid_member_in_interface)
3215 << (InvalidDecl-1) << Name;
3216 else
3217 Diag(Loc, diag::err_invalid_member_in_interface)
3218 << (InvalidDecl-1) << "";
3219 return nullptr;
3220 }
3221 }
3222
3223 // C++ 9.2p6: A member shall not be declared to have automatic storage
3224 // duration (auto, register) or with the extern storage-class-specifier.
3225 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class
3226 // data members and cannot be applied to names declared const or static,
3227 // and cannot be applied to reference members.
3228 switch (DS.getStorageClassSpec()) {
3229 case DeclSpec::SCS_unspecified:
3230 case DeclSpec::SCS_typedef:
3231 case DeclSpec::SCS_static:
3232 break;
3233 case DeclSpec::SCS_mutable:
3234 if (isFunc) {
3235 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function);
3236
3237 // FIXME: It would be nicer if the keyword was ignored only for this
3238 // declarator. Otherwise we could get follow-up errors.
3239 D.getMutableDeclSpec().ClearStorageClassSpecs();
3240 }
3241 break;
3242 default:
3243 Diag(DS.getStorageClassSpecLoc(),
3244 diag::err_storageclass_invalid_for_member);
3245 D.getMutableDeclSpec().ClearStorageClassSpecs();
3246 break;
3247 }
3248
3249 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified ||
3250 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) &&
3251 !isFunc);
3252
3253 if (DS.hasConstexprSpecifier() && isInstField) {
3254 SemaDiagnosticBuilder B =
3255 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr_member);
3256 SourceLocation ConstexprLoc = DS.getConstexprSpecLoc();
3257 if (InitStyle == ICIS_NoInit) {
3258 B << 0 << 0;
3259 if (D.getDeclSpec().getTypeQualifiers() & DeclSpec::TQ_const)
3260 B << FixItHint::CreateRemoval(ConstexprLoc);
3261 else {
3262 B << FixItHint::CreateReplacement(ConstexprLoc, "const");
3263 D.getMutableDeclSpec().ClearConstexprSpec();
3264 const char *PrevSpec;
3265 unsigned DiagID;
3266 bool Failed = D.getMutableDeclSpec().SetTypeQual(
3267 DeclSpec::TQ_const, ConstexprLoc, PrevSpec, DiagID, getLangOpts());
3268 (void)Failed;
3269 assert(!Failed && "Making a constexpr member const shouldn't fail")((!Failed && "Making a constexpr member const shouldn't fail"
) ? static_cast<void> (0) : __assert_fail ("!Failed && \"Making a constexpr member const shouldn't fail\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3269, __PRETTY_FUNCTION__))
;
3270 }
3271 } else {
3272 B << 1;
3273 const char *PrevSpec;
3274 unsigned DiagID;
3275 if (D.getMutableDeclSpec().SetStorageClassSpec(
3276 *this, DeclSpec::SCS_static, ConstexprLoc, PrevSpec, DiagID,
3277 Context.getPrintingPolicy())) {
3278 assert(DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&((DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&
"This is the only DeclSpec that should fail to be applied") ?
static_cast<void> (0) : __assert_fail ("DS.getStorageClassSpec() == DeclSpec::SCS_mutable && \"This is the only DeclSpec that should fail to be applied\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3279, __PRETTY_FUNCTION__))
3279 "This is the only DeclSpec that should fail to be applied")((DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&
"This is the only DeclSpec that should fail to be applied") ?
static_cast<void> (0) : __assert_fail ("DS.getStorageClassSpec() == DeclSpec::SCS_mutable && \"This is the only DeclSpec that should fail to be applied\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3279, __PRETTY_FUNCTION__))
;
3280 B << 1;
3281 } else {
3282 B << 0 << FixItHint::CreateInsertion(ConstexprLoc, "static ");
3283 isInstField = false;
3284 }
3285 }
3286 }
3287
3288 NamedDecl *Member;
3289 if (isInstField) {
3290 CXXScopeSpec &SS = D.getCXXScopeSpec();
3291
3292 // Data members must have identifiers for names.
3293 if (!Name.isIdentifier()) {
3294 Diag(Loc, diag::err_bad_variable_name)
3295 << Name;
3296 return nullptr;
3297 }
3298
3299 IdentifierInfo *II = Name.getAsIdentifierInfo();
3300
3301 // Member field could not be with "template" keyword.
3302 // So TemplateParameterLists should be empty in this case.
3303 if (TemplateParameterLists.size()) {
3304 TemplateParameterList* TemplateParams = TemplateParameterLists[0];
3305 if (TemplateParams->size()) {
3306 // There is no such thing as a member field template.
3307 Diag(D.getIdentifierLoc(), diag::err_template_member)
3308 << II
3309 << SourceRange(TemplateParams->getTemplateLoc(),
3310 TemplateParams->getRAngleLoc());
3311 } else {
3312 // There is an extraneous 'template<>' for this member.
3313 Diag(TemplateParams->getTemplateLoc(),
3314 diag::err_template_member_noparams)
3315 << II
3316 << SourceRange(TemplateParams->getTemplateLoc(),
3317 TemplateParams->getRAngleLoc());
3318 }
3319 return nullptr;
3320 }
3321
3322 if (SS.isSet() && !SS.isInvalid()) {
3323 // The user provided a superfluous scope specifier inside a class
3324 // definition:
3325 //
3326 // class X {
3327 // int X::member;
3328 // };
3329 if (DeclContext *DC = computeDeclContext(SS, false))
3330 diagnoseQualifiedDeclaration(SS, DC, Name, D.getIdentifierLoc(),
3331 D.getName().getKind() ==
3332 UnqualifiedIdKind::IK_TemplateId);
3333 else
3334 Diag(D.getIdentifierLoc(), diag::err_member_qualification)
3335 << Name << SS.getRange();
3336
3337 SS.clear();
3338 }
3339
3340 if (MSPropertyAttr) {
3341 Member = HandleMSProperty(S, cast<CXXRecordDecl>(CurContext), Loc, D,
3342 BitWidth, InitStyle, AS, *MSPropertyAttr);
3343 if (!Member)
3344 return nullptr;
3345 isInstField = false;
3346 } else {
3347 Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D,
3348 BitWidth, InitStyle, AS);
3349 if (!Member)
3350 return nullptr;
3351 }
3352
3353 CheckShadowInheritedFields(Loc, Name, cast<CXXRecordDecl>(CurContext));
3354 } else {
3355 Member = HandleDeclarator(S, D, TemplateParameterLists);
3356 if (!Member)
3357 return nullptr;
3358
3359 // Non-instance-fields can't have a bitfield.
3360 if (BitWidth) {
3361 if (Member->isInvalidDecl()) {
3362 // don't emit another diagnostic.
3363 } else if (isa<VarDecl>(Member) || isa<VarTemplateDecl>(Member)) {
3364 // C++ 9.6p3: A bit-field shall not be a static member.
3365 // "static member 'A' cannot be a bit-field"
3366 Diag(Loc, diag::err_static_not_bitfield)
3367 << Name << BitWidth->getSourceRange();
3368 } else if (isa<TypedefDecl>(Member)) {
3369 // "typedef member 'x' cannot be a bit-field"
3370 Diag(Loc, diag::err_typedef_not_bitfield)
3371 << Name << BitWidth->getSourceRange();
3372 } else {
3373 // A function typedef ("typedef int f(); f a;").
3374 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
3375 Diag(Loc, diag::err_not_integral_type_bitfield)
3376 << Name << cast<ValueDecl>(Member)->getType()
3377 << BitWidth->getSourceRange();
3378 }
3379
3380 BitWidth = nullptr;
3381 Member->setInvalidDecl();
3382 }
3383
3384 NamedDecl *NonTemplateMember = Member;
3385 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Member))
3386 NonTemplateMember = FunTmpl->getTemplatedDecl();
3387 else if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(Member))
3388 NonTemplateMember = VarTmpl->getTemplatedDecl();
3389
3390 Member->setAccess(AS);
3391
3392 // If we have declared a member function template or static data member
3393 // template, set the access of the templated declaration as well.
3394 if (NonTemplateMember != Member)
3395 NonTemplateMember->setAccess(AS);
3396
3397 // C++ [temp.deduct.guide]p3:
3398 // A deduction guide [...] for a member class template [shall be
3399 // declared] with the same access [as the template].
3400 if (auto *DG = dyn_cast<CXXDeductionGuideDecl>(NonTemplateMember)) {
3401 auto *TD = DG->getDeducedTemplate();
3402 // Access specifiers are only meaningful if both the template and the
3403 // deduction guide are from the same scope.
3404 if (AS != TD->getAccess() &&
3405 TD->getDeclContext()->getRedeclContext()->Equals(
3406 DG->getDeclContext()->getRedeclContext())) {
3407 Diag(DG->getBeginLoc(), diag::err_deduction_guide_wrong_access);
3408 Diag(TD->getBeginLoc(), diag::note_deduction_guide_template_access)
3409 << TD->getAccess();
3410 const AccessSpecDecl *LastAccessSpec = nullptr;
3411 for (const auto *D : cast<CXXRecordDecl>(CurContext)->decls()) {
3412 if (const auto *AccessSpec = dyn_cast<AccessSpecDecl>(D))
3413 LastAccessSpec = AccessSpec;
3414 }
3415 assert(LastAccessSpec && "differing access with no access specifier")((LastAccessSpec && "differing access with no access specifier"
) ? static_cast<void> (0) : __assert_fail ("LastAccessSpec && \"differing access with no access specifier\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3415, __PRETTY_FUNCTION__))
;
3416 Diag(LastAccessSpec->getBeginLoc(), diag::note_deduction_guide_access)
3417 << AS;
3418 }
3419 }
3420 }
3421
3422 if (VS.isOverrideSpecified())
3423 Member->addAttr(OverrideAttr::Create(Context, VS.getOverrideLoc(),
3424 AttributeCommonInfo::AS_Keyword));
3425 if (VS.isFinalSpecified())
3426 Member->addAttr(FinalAttr::Create(
3427 Context, VS.getFinalLoc(), AttributeCommonInfo::AS_Keyword,
3428 static_cast<FinalAttr::Spelling>(VS.isFinalSpelledSealed())));
3429
3430 if (VS.getLastLocation().isValid()) {
3431 // Update the end location of a method that has a virt-specifiers.
3432 if (CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Member))
3433 MD->setRangeEnd(VS.getLastLocation());
3434 }
3435
3436 CheckOverrideControl(Member);
3437
3438 assert((Name || isInstField) && "No identifier for non-field ?")(((Name || isInstField) && "No identifier for non-field ?"
) ? static_cast<void> (0) : __assert_fail ("(Name || isInstField) && \"No identifier for non-field ?\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3438, __PRETTY_FUNCTION__))
;
3439
3440 if (isInstField) {
3441 FieldDecl *FD = cast<FieldDecl>(Member);
3442 FieldCollector->Add(FD);
3443
3444 if (!Diags.isIgnored(diag::warn_unused_private_field, FD->getLocation())) {
3445 // Remember all explicit private FieldDecls that have a name, no side
3446 // effects and are not part of a dependent type declaration.
3447 if (!FD->isImplicit() && FD->getDeclName() &&
3448 FD->getAccess() == AS_private &&
3449 !FD->hasAttr<UnusedAttr>() &&
3450 !FD->getParent()->isDependentContext() &&
3451 !InitializationHasSideEffects(*FD))
3452 UnusedPrivateFields.insert(FD);
3453 }
3454 }
3455
3456 return Member;
3457}
3458
3459namespace {
3460 class UninitializedFieldVisitor
3461 : public EvaluatedExprVisitor<UninitializedFieldVisitor> {
3462 Sema &S;
3463 // List of Decls to generate a warning on. Also remove Decls that become
3464 // initialized.
3465 llvm::SmallPtrSetImpl<ValueDecl*> &Decls;
3466 // List of base classes of the record. Classes are removed after their
3467 // initializers.
3468 llvm::SmallPtrSetImpl<QualType> &BaseClasses;
3469 // Vector of decls to be removed from the Decl set prior to visiting the
3470 // nodes. These Decls may have been initialized in the prior initializer.
3471 llvm::SmallVector<ValueDecl*, 4> DeclsToRemove;
3472 // If non-null, add a note to the warning pointing back to the constructor.
3473 const CXXConstructorDecl *Constructor;
3474 // Variables to hold state when processing an initializer list. When
3475 // InitList is true, special case initialization of FieldDecls matching
3476 // InitListFieldDecl.
3477 bool InitList;
3478 FieldDecl *InitListFieldDecl;
3479 llvm::SmallVector<unsigned, 4> InitFieldIndex;
3480
3481 public:
3482 typedef EvaluatedExprVisitor<UninitializedFieldVisitor> Inherited;
3483 UninitializedFieldVisitor(Sema &S,
3484 llvm::SmallPtrSetImpl<ValueDecl*> &Decls,
3485 llvm::SmallPtrSetImpl<QualType> &BaseClasses)
3486 : Inherited(S.Context), S(S), Decls(Decls), BaseClasses(BaseClasses),
3487 Constructor(nullptr), InitList(false), InitListFieldDecl(nullptr) {}
3488
3489 // Returns true if the use of ME is not an uninitialized use.
3490 bool IsInitListMemberExprInitialized(MemberExpr *ME,
3491 bool CheckReferenceOnly) {
3492 llvm::SmallVector<FieldDecl*, 4> Fields;
3493 bool ReferenceField = false;
3494 while (ME) {
3495 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
3496 if (!FD)
3497 return false;
3498 Fields.push_back(FD);
3499 if (FD->getType()->isReferenceType())
3500 ReferenceField = true;
3501 ME = dyn_cast<MemberExpr>(ME->getBase()->IgnoreParenImpCasts());
3502 }
3503
3504 // Binding a reference to an uninitialized field is not an
3505 // uninitialized use.
3506 if (CheckReferenceOnly && !ReferenceField)
3507 return true;
3508
3509 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
3510 // Discard the first field since it is the field decl that is being
3511 // initialized.
3512 for (auto I = Fields.rbegin() + 1, E = Fields.rend(); I != E; ++I) {
3513 UsedFieldIndex.push_back((*I)->getFieldIndex());
3514 }
3515
3516 for (auto UsedIter = UsedFieldIndex.begin(),
3517 UsedEnd = UsedFieldIndex.end(),
3518 OrigIter = InitFieldIndex.begin(),
3519 OrigEnd = InitFieldIndex.end();
3520 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
3521 if (*UsedIter < *OrigIter)
3522 return true;
3523 if (*UsedIter > *OrigIter)
3524 break;
3525 }
3526
3527 return false;
3528 }
3529
3530 void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly,
3531 bool AddressOf) {
3532 if (isa<EnumConstantDecl>(ME->getMemberDecl()))
3533 return;
3534
3535 // FieldME is the inner-most MemberExpr that is not an anonymous struct
3536 // or union.
3537 MemberExpr *FieldME = ME;
3538
3539 bool AllPODFields = FieldME->getType().isPODType(S.Context);
3540
3541 Expr *Base = ME;
3542 while (MemberExpr *SubME =
3543 dyn_cast<MemberExpr>(Base->IgnoreParenImpCasts())) {
3544
3545 if (isa<VarDecl>(SubME->getMemberDecl()))
3546 return;
3547
3548 if (FieldDecl *FD = dyn_cast<FieldDecl>(SubME->getMemberDecl()))
3549 if (!FD->isAnonymousStructOrUnion())
3550 FieldME = SubME;
3551
3552 if (!FieldME->getType().isPODType(S.Context))
3553 AllPODFields = false;
3554
3555 Base = SubME->getBase();
3556 }
3557
3558 if (!isa<CXXThisExpr>(Base->IgnoreParenImpCasts()))
3559 return;
3560
3561 if (AddressOf && AllPODFields)
3562 return;
3563
3564 ValueDecl* FoundVD = FieldME->getMemberDecl();
3565
3566 if (ImplicitCastExpr *BaseCast = dyn_cast<ImplicitCastExpr>(Base)) {
3567 while (isa<ImplicitCastExpr>(BaseCast->getSubExpr())) {
3568 BaseCast = cast<ImplicitCastExpr>(BaseCast->getSubExpr());
3569 }
3570
3571 if (BaseCast->getCastKind() == CK_UncheckedDerivedToBase) {
3572 QualType T = BaseCast->getType();
3573 if (T->isPointerType() &&
3574 BaseClasses.count(T->getPointeeType())) {
3575 S.Diag(FieldME->getExprLoc(), diag::warn_base_class_is_uninit)
3576 << T->getPointeeType() << FoundVD;
3577 }
3578 }
3579 }
3580
3581 if (!Decls.count(FoundVD))
3582 return;
3583
3584 const bool IsReference = FoundVD->getType()->isReferenceType();
3585
3586 if (InitList && !AddressOf && FoundVD == InitListFieldDecl) {
3587 // Special checking for initializer lists.
3588 if (IsInitListMemberExprInitialized(ME, CheckReferenceOnly)) {
3589 return;
3590 }
3591 } else {
3592 // Prevent double warnings on use of unbounded references.
3593 if (CheckReferenceOnly && !IsReference)
3594 return;
3595 }
3596
3597 unsigned diag = IsReference
3598 ? diag::warn_reference_field_is_uninit
3599 : diag::warn_field_is_uninit;
3600 S.Diag(FieldME->getExprLoc(), diag) << FoundVD;
3601 if (Constructor)
3602 S.Diag(Constructor->getLocation(),
3603 diag::note_uninit_in_this_constructor)
3604 << (Constructor->isDefaultConstructor() && Constructor->isImplicit());
3605
3606 }
3607
3608 void HandleValue(Expr *E, bool AddressOf) {
3609 E = E->IgnoreParens();
3610
3611 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
3612 HandleMemberExpr(ME, false /*CheckReferenceOnly*/,
3613 AddressOf /*AddressOf*/);
3614 return;
3615 }
3616
3617 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
3618 Visit(CO->getCond());
3619 HandleValue(CO->getTrueExpr(), AddressOf);
3620 HandleValue(CO->getFalseExpr(), AddressOf);
3621 return;
3622 }
3623
3624 if (BinaryConditionalOperator *BCO =
3625 dyn_cast<BinaryConditionalOperator>(E)) {
3626 Visit(BCO->getCond());
3627 HandleValue(BCO->getFalseExpr(), AddressOf);
3628 return;
3629 }
3630
3631 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
3632 HandleValue(OVE->getSourceExpr(), AddressOf);
3633 return;
3634 }
3635
3636 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
3637 switch (BO->getOpcode()) {
3638 default:
3639 break;
3640 case(BO_PtrMemD):
3641 case(BO_PtrMemI):
3642 HandleValue(BO->getLHS(), AddressOf);
3643 Visit(BO->getRHS());
3644 return;
3645 case(BO_Comma):
3646 Visit(BO->getLHS());
3647 HandleValue(BO->getRHS(), AddressOf);
3648 return;
3649 }
3650 }
3651
3652 Visit(E);
3653 }
3654
3655 void CheckInitListExpr(InitListExpr *ILE) {
3656 InitFieldIndex.push_back(0);
3657 for (auto Child : ILE->children()) {
3658 if (InitListExpr *SubList = dyn_cast<InitListExpr>(Child)) {
3659 CheckInitListExpr(SubList);
3660 } else {
3661 Visit(Child);
3662 }
3663 ++InitFieldIndex.back();
3664 }
3665 InitFieldIndex.pop_back();
3666 }
3667
3668 void CheckInitializer(Expr *E, const CXXConstructorDecl *FieldConstructor,
3669 FieldDecl *Field, const Type *BaseClass) {
3670 // Remove Decls that may have been initialized in the previous
3671 // initializer.
3672 for (ValueDecl* VD : DeclsToRemove)
3673 Decls.erase(VD);
3674 DeclsToRemove.clear();
3675
3676 Constructor = FieldConstructor;
3677 InitListExpr *ILE = dyn_cast<InitListExpr>(E);
3678
3679 if (ILE && Field) {
3680 InitList = true;
3681 InitListFieldDecl = Field;
3682 InitFieldIndex.clear();
3683 CheckInitListExpr(ILE);
3684 } else {
3685 InitList = false;
3686 Visit(E);
3687 }
3688
3689 if (Field)
3690 Decls.erase(Field);
3691 if (BaseClass)
3692 BaseClasses.erase(BaseClass->getCanonicalTypeInternal());
3693 }
3694
3695 void VisitMemberExpr(MemberExpr *ME) {
3696 // All uses of unbounded reference fields will warn.
3697 HandleMemberExpr(ME, true /*CheckReferenceOnly*/, false /*AddressOf*/);
3698 }
3699
3700 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
3701 if (E->getCastKind() == CK_LValueToRValue) {
3702 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3703 return;
3704 }
3705
3706 Inherited::VisitImplicitCastExpr(E);
3707 }
3708
3709 void VisitCXXConstructExpr(CXXConstructExpr *E) {
3710 if (E->getConstructor()->isCopyConstructor()) {
3711 Expr *ArgExpr = E->getArg(0);
3712 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
3713 if (ILE->getNumInits() == 1)
3714 ArgExpr = ILE->getInit(0);
3715 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
3716 if (ICE->getCastKind() == CK_NoOp)
3717 ArgExpr = ICE->getSubExpr();
3718 HandleValue(ArgExpr, false /*AddressOf*/);
3719 return;
3720 }
3721 Inherited::VisitCXXConstructExpr(E);
3722 }
3723
3724 void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
3725 Expr *Callee = E->getCallee();
3726 if (isa<MemberExpr>(Callee)) {
3727 HandleValue(Callee, false /*AddressOf*/);
3728 for (auto Arg : E->arguments())
3729 Visit(Arg);
3730 return;
3731 }
3732
3733 Inherited::VisitCXXMemberCallExpr(E);
3734 }
3735
3736 void VisitCallExpr(CallExpr *E) {
3737 // Treat std::move as a use.
3738 if (E->isCallToStdMove()) {
3739 HandleValue(E->getArg(0), /*AddressOf=*/false);
3740 return;
3741 }
3742
3743 Inherited::VisitCallExpr(E);
3744 }
3745
3746 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
3747 Expr *Callee = E->getCallee();
3748
3749 if (isa<UnresolvedLookupExpr>(Callee))
3750 return Inherited::VisitCXXOperatorCallExpr(E);
3751
3752 Visit(Callee);
3753 for (auto Arg : E->arguments())
3754 HandleValue(Arg->IgnoreParenImpCasts(), false /*AddressOf*/);
3755 }
3756
3757 void VisitBinaryOperator(BinaryOperator *E) {
3758 // If a field assignment is detected, remove the field from the
3759 // uninitiailized field set.
3760 if (E->getOpcode() == BO_Assign)
3761 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getLHS()))
3762 if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3763 if (!FD->getType()->isReferenceType())
3764 DeclsToRemove.push_back(FD);
3765
3766 if (E->isCompoundAssignmentOp()) {
3767 HandleValue(E->getLHS(), false /*AddressOf*/);
3768 Visit(E->getRHS());
3769 return;
3770 }
3771
3772 Inherited::VisitBinaryOperator(E);
3773 }
3774
3775 void VisitUnaryOperator(UnaryOperator *E) {
3776 if (E->isIncrementDecrementOp()) {
3777 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3778 return;
3779 }
3780 if (E->getOpcode() == UO_AddrOf) {
3781 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getSubExpr())) {
3782 HandleValue(ME->getBase(), true /*AddressOf*/);
3783 return;
3784 }
3785 }
3786
3787 Inherited::VisitUnaryOperator(E);
3788 }
3789 };
3790
3791 // Diagnose value-uses of fields to initialize themselves, e.g.
3792 // foo(foo)
3793 // where foo is not also a parameter to the constructor.
3794 // Also diagnose across field uninitialized use such as
3795 // x(y), y(x)
3796 // TODO: implement -Wuninitialized and fold this into that framework.
3797 static void DiagnoseUninitializedFields(
3798 Sema &SemaRef, const CXXConstructorDecl *Constructor) {
3799
3800 if (SemaRef.getDiagnostics().isIgnored(diag::warn_field_is_uninit,
3801 Constructor->getLocation())) {
3802 return;
3803 }
3804
3805 if (Constructor->isInvalidDecl())
3806 return;
3807
3808 const CXXRecordDecl *RD = Constructor->getParent();
3809
3810 if (RD->isDependentContext())
3811 return;
3812
3813 // Holds fields that are uninitialized.
3814 llvm::SmallPtrSet<ValueDecl*, 4> UninitializedFields;
3815
3816 // At the beginning, all fields are uninitialized.
3817 for (auto *I : RD->decls()) {
3818 if (auto *FD = dyn_cast<FieldDecl>(I)) {
3819 UninitializedFields.insert(FD);
3820 } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(I)) {
3821 UninitializedFields.insert(IFD->getAnonField());
3822 }
3823 }
3824
3825 llvm::SmallPtrSet<QualType, 4> UninitializedBaseClasses;
3826 for (auto I : RD->bases())
3827 UninitializedBaseClasses.insert(I.getType().getCanonicalType());
3828
3829 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3830 return;
3831
3832 UninitializedFieldVisitor UninitializedChecker(SemaRef,
3833 UninitializedFields,
3834 UninitializedBaseClasses);
3835
3836 for (const auto *FieldInit : Constructor->inits()) {
3837 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3838 break;
3839
3840 Expr *InitExpr = FieldInit->getInit();
3841 if (!InitExpr)
3842 continue;
3843
3844 if (CXXDefaultInitExpr *Default =
3845 dyn_cast<CXXDefaultInitExpr>(InitExpr)) {
3846 InitExpr = Default->getExpr();
3847 if (!InitExpr)
3848 continue;
3849 // In class initializers will point to the constructor.
3850 UninitializedChecker.CheckInitializer(InitExpr, Constructor,
3851 FieldInit->getAnyMember(),
3852 FieldInit->getBaseClass());
3853 } else {
3854 UninitializedChecker.CheckInitializer(InitExpr, nullptr,
3855 FieldInit->getAnyMember(),
3856 FieldInit->getBaseClass());
3857 }
3858 }
3859 }
3860} // namespace
3861
3862/// Enter a new C++ default initializer scope. After calling this, the
3863/// caller must call \ref ActOnFinishCXXInClassMemberInitializer, even if
3864/// parsing or instantiating the initializer failed.
3865void Sema::ActOnStartCXXInClassMemberInitializer() {
3866 // Create a synthetic function scope to represent the call to the constructor
3867 // that notionally surrounds a use of this initializer.
3868 PushFunctionScope();
3869}
3870
3871void Sema::ActOnStartTrailingRequiresClause(Scope *S, Declarator &D) {
3872 if (!D.isFunctionDeclarator())
3873 return;
3874 auto &FTI = D.getFunctionTypeInfo();
3875 if (!FTI.Params)
3876 return;
3877 for (auto &Param : ArrayRef<DeclaratorChunk::ParamInfo>(FTI.Params,
3878 FTI.NumParams)) {
3879 auto *ParamDecl = cast<NamedDecl>(Param.Param);
3880 if (ParamDecl->getDeclName())
3881 PushOnScopeChains(ParamDecl, S, /*AddToContext=*/false);
3882 }
3883}
3884
3885ExprResult Sema::ActOnFinishTrailingRequiresClause(ExprResult ConstraintExpr) {
3886 if (ConstraintExpr.isInvalid())
3887 return ExprError();
3888 return CorrectDelayedTyposInExpr(ConstraintExpr);
3889}
3890
3891/// This is invoked after parsing an in-class initializer for a
3892/// non-static C++ class member, and after instantiating an in-class initializer
3893/// in a class template. Such actions are deferred until the class is complete.
3894void Sema::ActOnFinishCXXInClassMemberInitializer(Decl *D,
3895 SourceLocation InitLoc,
3896 Expr *InitExpr) {
3897 // Pop the notional constructor scope we created earlier.
3898 PopFunctionScopeInfo(nullptr, D);
3899
3900 FieldDecl *FD = dyn_cast<FieldDecl>(D);
1
Assuming 'D' is not a 'FieldDecl'
2
'FD' initialized to a null pointer value
3901 assert((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) &&(((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle
() != ICIS_NoInit) && "must set init style when field is created"
) ? static_cast<void> (0) : __assert_fail ("(isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) && \"must set init style when field is created\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3902, __PRETTY_FUNCTION__))
3
Assuming 'D' is a 'MSPropertyDecl'
4
'?' condition is true
3902 "must set init style when field is created")(((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle
() != ICIS_NoInit) && "must set init style when field is created"
) ? static_cast<void> (0) : __assert_fail ("(isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) && \"must set init style when field is created\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 3902, __PRETTY_FUNCTION__))
;
3903
3904 if (!InitExpr) {
5
Assuming 'InitExpr' is non-null
6
Taking false branch
3905 D->setInvalidDecl();
3906 if (FD)
3907 FD->removeInClassInitializer();
3908 return;
3909 }
3910
3911 if (DiagnoseUnexpandedParameterPack(InitExpr, UPPC_Initializer)) {
7
Assuming the condition is true
8
Taking true branch
3912 FD->setInvalidDecl();
9
Called C++ object pointer is null
3913 FD->removeInClassInitializer();
3914 return;
3915 }
3916
3917 ExprResult Init = InitExpr;
3918 if (!FD->getType()->isDependentType() && !InitExpr->isTypeDependent()) {
3919 InitializedEntity Entity =
3920 InitializedEntity::InitializeMemberFromDefaultMemberInitializer(FD);
3921 InitializationKind Kind =
3922 FD->getInClassInitStyle() == ICIS_ListInit
3923 ? InitializationKind::CreateDirectList(InitExpr->getBeginLoc(),
3924 InitExpr->getBeginLoc(),
3925 InitExpr->getEndLoc())
3926 : InitializationKind::CreateCopy(InitExpr->getBeginLoc(), InitLoc);
3927 InitializationSequence Seq(*this, Entity, Kind, InitExpr);
3928 Init = Seq.Perform(*this, Entity, Kind, InitExpr);
3929 if (Init.isInvalid()) {
3930 FD->setInvalidDecl();
3931 return;
3932 }
3933 }
3934
3935 // C++11 [class.base.init]p7:
3936 // The initialization of each base and member constitutes a
3937 // full-expression.
3938 Init = ActOnFinishFullExpr(Init.get(), InitLoc, /*DiscardedValue*/ false);
3939 if (Init.isInvalid()) {
3940 FD->setInvalidDecl();
3941 return;
3942 }
3943
3944 InitExpr = Init.get();
3945
3946 FD->setInClassInitializer(InitExpr);
3947}
3948
3949/// Find the direct and/or virtual base specifiers that
3950/// correspond to the given base type, for use in base initialization
3951/// within a constructor.
3952static bool FindBaseInitializer(Sema &SemaRef,
3953 CXXRecordDecl *ClassDecl,
3954 QualType BaseType,
3955 const CXXBaseSpecifier *&DirectBaseSpec,
3956 const CXXBaseSpecifier *&VirtualBaseSpec) {
3957 // First, check for a direct base class.
3958 DirectBaseSpec = nullptr;
3959 for (const auto &Base : ClassDecl->bases()) {
3960 if (SemaRef.Context.hasSameUnqualifiedType(BaseType, Base.getType())) {
3961 // We found a direct base of this type. That's what we're
3962 // initializing.
3963 DirectBaseSpec = &Base;
3964 break;
3965 }
3966 }
3967
3968 // Check for a virtual base class.
3969 // FIXME: We might be able to short-circuit this if we know in advance that
3970 // there are no virtual bases.
3971 VirtualBaseSpec = nullptr;
3972 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) {
3973 // We haven't found a base yet; search the class hierarchy for a
3974 // virtual base class.
3975 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
3976 /*DetectVirtual=*/false);
3977 if (SemaRef.IsDerivedFrom(ClassDecl->getLocation(),
3978 SemaRef.Context.getTypeDeclType(ClassDecl),
3979 BaseType, Paths)) {
3980 for (CXXBasePaths::paths_iterator Path = Paths.begin();
3981 Path != Paths.end(); ++Path) {
3982 if (Path->back().Base->isVirtual()) {
3983 VirtualBaseSpec = Path->back().Base;
3984 break;
3985 }
3986 }
3987 }
3988 }
3989
3990 return DirectBaseSpec || VirtualBaseSpec;
3991}
3992
3993/// Handle a C++ member initializer using braced-init-list syntax.
3994MemInitResult
3995Sema::ActOnMemInitializer(Decl *ConstructorD,
3996 Scope *S,
3997 CXXScopeSpec &SS,
3998 IdentifierInfo *MemberOrBase,
3999 ParsedType TemplateTypeTy,
4000 const DeclSpec &DS,
4001 SourceLocation IdLoc,
4002 Expr *InitList,
4003 SourceLocation EllipsisLoc) {
4004 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
4005 DS, IdLoc, InitList,
4006 EllipsisLoc);
4007}
4008
4009/// Handle a C++ member initializer using parentheses syntax.
4010MemInitResult
4011Sema::ActOnMemInitializer(Decl *ConstructorD,
4012 Scope *S,
4013 CXXScopeSpec &SS,
4014 IdentifierInfo *MemberOrBase,
4015 ParsedType TemplateTypeTy,
4016 const DeclSpec &DS,
4017 SourceLocation IdLoc,
4018 SourceLocation LParenLoc,
4019 ArrayRef<Expr *> Args,
4020 SourceLocation RParenLoc,
4021 SourceLocation EllipsisLoc) {
4022 Expr *List = ParenListExpr::Create(Context, LParenLoc, Args, RParenLoc);
4023 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
4024 DS, IdLoc, List, EllipsisLoc);
4025}
4026
4027namespace {
4028
4029// Callback to only accept typo corrections that can be a valid C++ member
4030// intializer: either a non-static field member or a base class.
4031class MemInitializerValidatorCCC final : public CorrectionCandidateCallback {
4032public:
4033 explicit MemInitializerValidatorCCC(CXXRecordDecl *ClassDecl)
4034 : ClassDecl(ClassDecl) {}
4035
4036 bool ValidateCandidate(const TypoCorrection &candidate) override {
4037 if (NamedDecl *ND = candidate.getCorrectionDecl()) {
4038 if (FieldDecl *Member = dyn_cast<FieldDecl>(ND))
4039 return Member->getDeclContext()->getRedeclContext()->Equals(ClassDecl);
4040 return isa<TypeDecl>(ND);
4041 }
4042 return false;
4043 }
4044
4045 std::unique_ptr<CorrectionCandidateCallback> clone() override {
4046 return std::make_unique<MemInitializerValidatorCCC>(*this);
4047 }
4048
4049private:
4050 CXXRecordDecl *ClassDecl;
4051};
4052
4053}
4054
4055ValueDecl *Sema::tryLookupCtorInitMemberDecl(CXXRecordDecl *ClassDecl,
4056 CXXScopeSpec &SS,
4057 ParsedType TemplateTypeTy,
4058 IdentifierInfo *MemberOrBase) {
4059 if (SS.getScopeRep() || TemplateTypeTy)
4060 return nullptr;
4061 DeclContext::lookup_result Result = ClassDecl->lookup(MemberOrBase);
4062 if (Result.empty())
4063 return nullptr;
4064 ValueDecl *Member;
4065 if ((Member = dyn_cast<FieldDecl>(Result.front())) ||
4066 (Member = dyn_cast<IndirectFieldDecl>(Result.front())))
4067 return Member;
4068 return nullptr;
4069}
4070
4071/// Handle a C++ member initializer.
4072MemInitResult
4073Sema::BuildMemInitializer(Decl *ConstructorD,
4074 Scope *S,
4075 CXXScopeSpec &SS,
4076 IdentifierInfo *MemberOrBase,
4077 ParsedType TemplateTypeTy,
4078 const DeclSpec &DS,
4079 SourceLocation IdLoc,
4080 Expr *Init,
4081 SourceLocation EllipsisLoc) {
4082 ExprResult Res = CorrectDelayedTyposInExpr(Init);
4083 if (!Res.isUsable())
4084 return true;
4085 Init = Res.get();
4086
4087 if (!ConstructorD)
4088 return true;
4089
4090 AdjustDeclIfTemplate(ConstructorD);
4091
4092 CXXConstructorDecl *Constructor
4093 = dyn_cast<CXXConstructorDecl>(ConstructorD);
4094 if (!Constructor) {
4095 // The user wrote a constructor initializer on a function that is
4096 // not a C++ constructor. Ignore the error for now, because we may
4097 // have more member initializers coming; we'll diagnose it just
4098 // once in ActOnMemInitializers.
4099 return true;
4100 }
4101
4102 CXXRecordDecl *ClassDecl = Constructor->getParent();
4103
4104 // C++ [class.base.init]p2:
4105 // Names in a mem-initializer-id are looked up in the scope of the
4106 // constructor's class and, if not found in that scope, are looked
4107 // up in the scope containing the constructor's definition.
4108 // [Note: if the constructor's class contains a member with the
4109 // same name as a direct or virtual base class of the class, a
4110 // mem-initializer-id naming the member or base class and composed
4111 // of a single identifier refers to the class member. A
4112 // mem-initializer-id for the hidden base class may be specified
4113 // using a qualified name. ]
4114
4115 // Look for a member, first.
4116 if (ValueDecl *Member = tryLookupCtorInitMemberDecl(
4117 ClassDecl, SS, TemplateTypeTy, MemberOrBase)) {
4118 if (EllipsisLoc.isValid())
4119 Diag(EllipsisLoc, diag::err_pack_expansion_member_init)
4120 << MemberOrBase
4121 << SourceRange(IdLoc, Init->getSourceRange().getEnd());
4122
4123 return BuildMemberInitializer(Member, Init, IdLoc);
4124 }
4125 // It didn't name a member, so see if it names a class.
4126 QualType BaseType;
4127 TypeSourceInfo *TInfo = nullptr;
4128
4129 if (TemplateTypeTy) {
4130 BaseType = GetTypeFromParser(TemplateTypeTy, &TInfo);
4131 if (BaseType.isNull())
4132 return true;
4133 } else if (DS.getTypeSpecType() == TST_decltype) {
4134 BaseType = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
4135 } else if (DS.getTypeSpecType() == TST_decltype_auto) {
4136 Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
4137 return true;
4138 } else {
4139 LookupResult R(*this, MemberOrBase, IdLoc, LookupOrdinaryName);
4140 LookupParsedName(R, S, &SS);
4141
4142 TypeDecl *TyD = R.getAsSingle<TypeDecl>();
4143 if (!TyD) {
4144 if (R.isAmbiguous()) return true;
4145
4146 // We don't want access-control diagnostics here.
4147 R.suppressDiagnostics();
4148
4149 if (SS.isSet() && isDependentScopeSpecifier(SS)) {
4150 bool NotUnknownSpecialization = false;
4151 DeclContext *DC = computeDeclContext(SS, false);
4152 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(DC))
4153 NotUnknownSpecialization = !Record->hasAnyDependentBases();
4154
4155 if (!NotUnknownSpecialization) {
4156 // When the scope specifier can refer to a member of an unknown
4157 // specialization, we take it as a type name.
4158 BaseType = CheckTypenameType(ETK_None, SourceLocation(),
4159 SS.getWithLocInContext(Context),
4160 *MemberOrBase, IdLoc);
4161 if (BaseType.isNull())
4162 return true;
4163
4164 TInfo = Context.CreateTypeSourceInfo(BaseType);
4165 DependentNameTypeLoc TL =
4166 TInfo->getTypeLoc().castAs<DependentNameTypeLoc>();
4167 if (!TL.isNull()) {
4168 TL.setNameLoc(IdLoc);
4169 TL.setElaboratedKeywordLoc(SourceLocation());
4170 TL.setQualifierLoc(SS.getWithLocInContext(Context));
4171 }
4172
4173 R.clear();
4174 R.setLookupName(MemberOrBase);
4175 }
4176 }
4177
4178 // If no results were found, try to correct typos.
4179 TypoCorrection Corr;
4180 MemInitializerValidatorCCC CCC(ClassDecl);
4181 if (R.empty() && BaseType.isNull() &&
4182 (Corr = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
4183 CCC, CTK_ErrorRecovery, ClassDecl))) {
4184 if (FieldDecl *Member = Corr.getCorrectionDeclAs<FieldDecl>()) {
4185 // We have found a non-static data member with a similar
4186 // name to what was typed; complain and initialize that
4187 // member.
4188 diagnoseTypo(Corr,
4189 PDiag(diag::err_mem_init_not_member_or_class_suggest)
4190 << MemberOrBase << true);
4191 return BuildMemberInitializer(Member, Init, IdLoc);
4192 } else if (TypeDecl *Type = Corr.getCorrectionDeclAs<TypeDecl>()) {
4193 const CXXBaseSpecifier *DirectBaseSpec;
4194 const CXXBaseSpecifier *VirtualBaseSpec;
4195 if (FindBaseInitializer(*this, ClassDecl,
4196 Context.getTypeDeclType(Type),
4197 DirectBaseSpec, VirtualBaseSpec)) {
4198 // We have found a direct or virtual base class with a
4199 // similar name to what was typed; complain and initialize
4200 // that base class.
4201 diagnoseTypo(Corr,
4202 PDiag(diag::err_mem_init_not_member_or_class_suggest)
4203 << MemberOrBase << false,
4204 PDiag() /*Suppress note, we provide our own.*/);
4205
4206 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec ? DirectBaseSpec
4207 : VirtualBaseSpec;
4208 Diag(BaseSpec->getBeginLoc(), diag::note_base_class_specified_here)
4209 << BaseSpec->getType() << BaseSpec->getSourceRange();
4210
4211 TyD = Type;
4212 }
4213 }
4214 }
4215
4216 if (!TyD && BaseType.isNull()) {
4217 Diag(IdLoc, diag::err_mem_init_not_member_or_class)
4218 << MemberOrBase << SourceRange(IdLoc,Init->getSourceRange().getEnd());
4219 return true;
4220 }
4221 }
4222
4223 if (BaseType.isNull()) {
4224 BaseType = Context.getTypeDeclType(TyD);
4225 MarkAnyDeclReferenced(TyD->getLocation(), TyD, /*OdrUse=*/false);
4226 if (SS.isSet()) {
4227 BaseType = Context.getElaboratedType(ETK_None, SS.getScopeRep(),
4228 BaseType);
4229 TInfo = Context.CreateTypeSourceInfo(BaseType);
4230 ElaboratedTypeLoc TL = TInfo->getTypeLoc().castAs<ElaboratedTypeLoc>();
4231 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
4232 TL.setElaboratedKeywordLoc(SourceLocation());
4233 TL.setQualifierLoc(SS.getWithLocInContext(Context));
4234 }
4235 }
4236 }
4237
4238 if (!TInfo)
4239 TInfo = Context.getTrivialTypeSourceInfo(BaseType, IdLoc);
4240
4241 return BuildBaseInitializer(BaseType, TInfo, Init, ClassDecl, EllipsisLoc);
4242}
4243
4244MemInitResult
4245Sema::BuildMemberInitializer(ValueDecl *Member, Expr *Init,
4246 SourceLocation IdLoc) {
4247 FieldDecl *DirectMember = dyn_cast<FieldDecl>(Member);
4248 IndirectFieldDecl *IndirectMember = dyn_cast<IndirectFieldDecl>(Member);
4249 assert((DirectMember || IndirectMember) &&(((DirectMember || IndirectMember) && "Member must be a FieldDecl or IndirectFieldDecl"
) ? static_cast<void> (0) : __assert_fail ("(DirectMember || IndirectMember) && \"Member must be a FieldDecl or IndirectFieldDecl\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 4250, __PRETTY_FUNCTION__))
4250 "Member must be a FieldDecl or IndirectFieldDecl")(((DirectMember || IndirectMember) && "Member must be a FieldDecl or IndirectFieldDecl"
) ? static_cast<void> (0) : __assert_fail ("(DirectMember || IndirectMember) && \"Member must be a FieldDecl or IndirectFieldDecl\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 4250, __PRETTY_FUNCTION__))
;
4251
4252 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
4253 return true;
4254
4255 if (Member->isInvalidDecl())
4256 return true;
4257
4258 MultiExprArg Args;
4259 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4260 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4261 } else if (InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
4262 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
4263 } else {
4264 // Template instantiation doesn't reconstruct ParenListExprs for us.
4265 Args = Init;
4266 }
4267
4268 SourceRange InitRange = Init->getSourceRange();
4269
4270 if (Member->getType()->isDependentType() || Init->isTypeDependent()) {
4271 // Can't check initialization for a member of dependent type or when
4272 // any of the arguments are type-dependent expressions.
4273 DiscardCleanupsInEvaluationContext();
4274 } else {
4275 bool InitList = false;
4276 if (isa<InitListExpr>(Init)) {
4277 InitList = true;
4278 Args = Init;
4279 }
4280
4281 // Initialize the member.
4282 InitializedEntity MemberEntity =
4283 DirectMember ? InitializedEntity::InitializeMember(DirectMember, nullptr)
4284 : InitializedEntity::InitializeMember(IndirectMember,
4285 nullptr);
4286 InitializationKind Kind =
4287 InitList ? InitializationKind::CreateDirectList(
4288 IdLoc, Init->getBeginLoc(), Init->getEndLoc())
4289 : InitializationKind::CreateDirect(IdLoc, InitRange.getBegin(),
4290 InitRange.getEnd());
4291
4292 InitializationSequence InitSeq(*this, MemberEntity, Kind, Args);
4293 ExprResult MemberInit = InitSeq.Perform(*this, MemberEntity, Kind, Args,
4294 nullptr);
4295 if (MemberInit.isInvalid())
4296 return true;
4297
4298 // C++11 [class.base.init]p7:
4299 // The initialization of each base and member constitutes a
4300 // full-expression.
4301 MemberInit = ActOnFinishFullExpr(MemberInit.get(), InitRange.getBegin(),
4302 /*DiscardedValue*/ false);
4303 if (MemberInit.isInvalid())
4304 return true;
4305
4306 Init = MemberInit.get();
4307 }
4308
4309 if (DirectMember) {
4310 return new (Context) CXXCtorInitializer(Context, DirectMember, IdLoc,
4311 InitRange.getBegin(), Init,
4312 InitRange.getEnd());
4313 } else {
4314 return new (Context) CXXCtorInitializer(Context, IndirectMember, IdLoc,
4315 InitRange.getBegin(), Init,
4316 InitRange.getEnd());
4317 }
4318}
4319
4320MemInitResult
4321Sema::BuildDelegatingInitializer(TypeSourceInfo *TInfo, Expr *Init,
4322 CXXRecordDecl *ClassDecl) {
4323 SourceLocation NameLoc = TInfo->getTypeLoc().getLocalSourceRange().getBegin();
4324 if (!LangOpts.CPlusPlus11)
4325 return Diag(NameLoc, diag::err_delegating_ctor)
4326 << TInfo->getTypeLoc().getLocalSourceRange();
4327 Diag(NameLoc, diag::warn_cxx98_compat_delegating_ctor);
4328
4329 bool InitList = true;
4330 MultiExprArg Args = Init;
4331 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4332 InitList = false;
4333 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4334 }
4335
4336 SourceRange InitRange = Init->getSourceRange();
4337 // Initialize the object.
4338 InitializedEntity DelegationEntity = InitializedEntity::InitializeDelegation(
4339 QualType(ClassDecl->getTypeForDecl(), 0));
4340 InitializationKind Kind =
4341 InitList ? InitializationKind::CreateDirectList(
4342 NameLoc, Init->getBeginLoc(), Init->getEndLoc())
4343 : InitializationKind::CreateDirect(NameLoc, InitRange.getBegin(),
4344 InitRange.getEnd());
4345 InitializationSequence InitSeq(*this, DelegationEntity, Kind, Args);
4346 ExprResult DelegationInit = InitSeq.Perform(*this, DelegationEntity, Kind,
4347 Args, nullptr);
4348 if (DelegationInit.isInvalid())
4349 return true;
4350
4351 assert(cast<CXXConstructExpr>(DelegationInit.get())->getConstructor() &&((cast<CXXConstructExpr>(DelegationInit.get())->getConstructor
() && "Delegating constructor with no target?") ? static_cast
<void> (0) : __assert_fail ("cast<CXXConstructExpr>(DelegationInit.get())->getConstructor() && \"Delegating constructor with no target?\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 4352, __PRETTY_FUNCTION__))
4352 "Delegating constructor with no target?")((cast<CXXConstructExpr>(DelegationInit.get())->getConstructor
() && "Delegating constructor with no target?") ? static_cast
<void> (0) : __assert_fail ("cast<CXXConstructExpr>(DelegationInit.get())->getConstructor() && \"Delegating constructor with no target?\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 4352, __PRETTY_FUNCTION__))
;
4353
4354 // C++11 [class.base.init]p7:
4355 // The initialization of each base and member constitutes a
4356 // full-expression.
4357 DelegationInit = ActOnFinishFullExpr(
4358 DelegationInit.get(), InitRange.getBegin(), /*DiscardedValue*/ false);
4359 if (DelegationInit.isInvalid())
4360 return true;
4361
4362 // If we are in a dependent context, template instantiation will
4363 // perform this type-checking again. Just save the arguments that we
4364 // received in a ParenListExpr.
4365 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4366 // of the information that we have about the base
4367 // initializer. However, deconstructing the ASTs is a dicey process,
4368 // and this approach is far more likely to get the corner cases right.
4369 if (CurContext->isDependentContext())
4370 DelegationInit = Init;
4371
4372 return new (Context) CXXCtorInitializer(Context, TInfo, InitRange.getBegin(),
4373 DelegationInit.getAs<Expr>(),
4374 InitRange.getEnd());
4375}
4376
4377MemInitResult
4378Sema::BuildBaseInitializer(QualType BaseType, TypeSourceInfo *BaseTInfo,
4379 Expr *Init, CXXRecordDecl *ClassDecl,
4380 SourceLocation EllipsisLoc) {
4381 SourceLocation BaseLoc
4382 = BaseTInfo->getTypeLoc().getLocalSourceRange().getBegin();
4383
4384 if (!BaseType->isDependentType() && !BaseType->isRecordType())
4385 return Diag(BaseLoc, diag::err_base_init_does_not_name_class)
4386 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
4387
4388 // C++ [class.base.init]p2:
4389 // [...] Unless the mem-initializer-id names a nonstatic data
4390 // member of the constructor's class or a direct or virtual base
4391 // of that class, the mem-initializer is ill-formed. A
4392 // mem-initializer-list can initialize a base class using any
4393 // name that denotes that base class type.
4394 bool Dependent = BaseType->isDependentType() || Init->isTypeDependent();
4395
4396 SourceRange InitRange = Init->getSourceRange();
4397 if (EllipsisLoc.isValid()) {
4398 // This is a pack expansion.
4399 if (!BaseType->containsUnexpandedParameterPack()) {
4400 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
4401 << SourceRange(BaseLoc, InitRange.getEnd());
4402
4403 EllipsisLoc = SourceLocation();
4404 }
4405 } else {
4406 // Check for any unexpanded parameter packs.
4407 if (DiagnoseUnexpandedParameterPack(BaseLoc, BaseTInfo, UPPC_Initializer))
4408 return true;
4409
4410 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
4411 return true;
4412 }
4413
4414 // Check for direct and virtual base classes.
4415 const CXXBaseSpecifier *DirectBaseSpec = nullptr;
4416 const CXXBaseSpecifier *VirtualBaseSpec = nullptr;
4417 if (!Dependent) {
4418 if (Context.hasSameUnqualifiedType(QualType(ClassDecl->getTypeForDecl(),0),
4419 BaseType))
4420 return BuildDelegatingInitializer(BaseTInfo, Init, ClassDecl);
4421
4422 FindBaseInitializer(*this, ClassDecl, BaseType, DirectBaseSpec,
4423 VirtualBaseSpec);
4424
4425 // C++ [base.class.init]p2:
4426 // Unless the mem-initializer-id names a nonstatic data member of the
4427 // constructor's class or a direct or virtual base of that class, the
4428 // mem-initializer is ill-formed.
4429 if (!DirectBaseSpec && !VirtualBaseSpec) {
4430 // If the class has any dependent bases, then it's possible that
4431 // one of those types will resolve to the same type as
4432 // BaseType. Therefore, just treat this as a dependent base
4433 // class initialization. FIXME: Should we try to check the
4434 // initialization anyway? It seems odd.
4435 if (ClassDecl->hasAnyDependentBases())
4436 Dependent = true;
4437 else
4438 return Diag(BaseLoc, diag::err_not_direct_base_or_virtual)
4439 << BaseType << Context.getTypeDeclType(ClassDecl)
4440 << BaseTInfo->getTypeLoc().getLocalSourceRange();
4441 }
4442 }
4443
4444 if (Dependent) {
4445 DiscardCleanupsInEvaluationContext();
4446
4447 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4448 /*IsVirtual=*/false,
4449 InitRange.getBegin(), Init,
4450 InitRange.getEnd(), EllipsisLoc);
4451 }
4452
4453 // C++ [base.class.init]p2:
4454 // If a mem-initializer-id is ambiguous because it designates both
4455 // a direct non-virtual base class and an inherited virtual base
4456 // class, the mem-initializer is ill-formed.
4457 if (DirectBaseSpec && VirtualBaseSpec)
4458 return Diag(BaseLoc, diag::err_base_init_direct_and_virtual)
4459 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
4460
4461 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec;
4462 if (!BaseSpec)
4463 BaseSpec = VirtualBaseSpec;
4464
4465 // Initialize the base.
4466 bool InitList = true;
4467 MultiExprArg Args = Init;
4468 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4469 InitList = false;
4470 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4471 }
4472
4473 InitializedEntity BaseEntity =
4474 InitializedEntity::InitializeBase(Context, BaseSpec, VirtualBaseSpec);
4475 InitializationKind Kind =
4476 InitList ? InitializationKind::CreateDirectList(BaseLoc)
4477 : InitializationKind::CreateDirect(BaseLoc, InitRange.getBegin(),
4478 InitRange.getEnd());
4479 InitializationSequence InitSeq(*this, BaseEntity, Kind, Args);
4480 ExprResult BaseInit = InitSeq.Perform(*this, BaseEntity, Kind, Args, nullptr);
4481 if (BaseInit.isInvalid())
4482 return true;
4483
4484 // C++11 [class.base.init]p7:
4485 // The initialization of each base and member constitutes a
4486 // full-expression.
4487 BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin(),
4488 /*DiscardedValue*/ false);
4489 if (BaseInit.isInvalid())
4490 return true;
4491
4492 // If we are in a dependent context, template instantiation will
4493 // perform this type-checking again. Just save the arguments that we
4494 // received in a ParenListExpr.
4495 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4496 // of the information that we have about the base
4497 // initializer. However, deconstructing the ASTs is a dicey process,
4498 // and this approach is far more likely to get the corner cases right.
4499 if (CurContext->isDependentContext())
4500 BaseInit = Init;
4501
4502 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4503 BaseSpec->isVirtual(),
4504 InitRange.getBegin(),
4505 BaseInit.getAs<Expr>(),
4506 InitRange.getEnd(), EllipsisLoc);
4507}
4508
4509// Create a static_cast\<T&&>(expr).
4510static Expr *CastForMoving(Sema &SemaRef, Expr *E, QualType T = QualType()) {
4511 if (T.isNull()) T = E->getType();
4512 QualType TargetType = SemaRef.BuildReferenceType(
4513 T, /*SpelledAsLValue*/false, SourceLocation(), DeclarationName());
4514 SourceLocation ExprLoc = E->getBeginLoc();
4515 TypeSourceInfo *TargetLoc = SemaRef.Context.getTrivialTypeSourceInfo(
4516 TargetType, ExprLoc);
4517
4518 return SemaRef.BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E,
4519 SourceRange(ExprLoc, ExprLoc),
4520 E->getSourceRange()).get();
4521}
4522
4523/// ImplicitInitializerKind - How an implicit base or member initializer should
4524/// initialize its base or member.
4525enum ImplicitInitializerKind {
4526 IIK_Default,
4527 IIK_Copy,
4528 IIK_Move,
4529 IIK_Inherit
4530};
4531
4532static bool
4533BuildImplicitBaseInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4534 ImplicitInitializerKind ImplicitInitKind,
4535 CXXBaseSpecifier *BaseSpec,
4536 bool IsInheritedVirtualBase,
4537 CXXCtorInitializer *&CXXBaseInit) {
4538 InitializedEntity InitEntity
4539 = InitializedEntity::InitializeBase(SemaRef.Context, BaseSpec,
4540 IsInheritedVirtualBase);
4541
4542 ExprResult BaseInit;
4543
4544 switch (ImplicitInitKind) {
4545 case IIK_Inherit:
4546 case IIK_Default: {
4547 InitializationKind InitKind
4548 = InitializationKind::CreateDefault(Constructor->getLocation());
4549 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4550 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4551 break;
4552 }
4553
4554 case IIK_Move:
4555 case IIK_Copy: {
4556 bool Moving = ImplicitInitKind == IIK_Move;
4557 ParmVarDecl *Param = Constructor->getParamDecl(0);
4558 QualType ParamType = Param->getType().getNonReferenceType();
4559
4560 Expr *CopyCtorArg =
4561 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4562 SourceLocation(), Param, false,
4563 Constructor->getLocation(), ParamType,
4564 VK_LValue, nullptr);
4565
4566 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(CopyCtorArg));
4567
4568 // Cast to the base class to avoid ambiguities.
4569 QualType ArgTy =
4570 SemaRef.Context.getQualifiedType(BaseSpec->getType().getUnqualifiedType(),
4571 ParamType.getQualifiers());
4572
4573 if (Moving) {
4574 CopyCtorArg = CastForMoving(SemaRef, CopyCtorArg);
4575 }
4576
4577 CXXCastPath BasePath;
4578 BasePath.push_back(BaseSpec);
4579 CopyCtorArg = SemaRef.ImpCastExprToType(CopyCtorArg, ArgTy,
4580 CK_UncheckedDerivedToBase,
4581 Moving ? VK_XValue : VK_LValue,
4582 &BasePath).get();
4583
4584 InitializationKind InitKind
4585 = InitializationKind::CreateDirect(Constructor->getLocation(),
4586 SourceLocation(), SourceLocation());
4587 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, CopyCtorArg);
4588 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, CopyCtorArg);
4589 break;
4590 }
4591 }
4592
4593 BaseInit = SemaRef.MaybeCreateExprWithCleanups(BaseInit);
4594 if (BaseInit.isInvalid())
4595 return true;
4596
4597 CXXBaseInit =
4598 new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4599 SemaRef.Context.getTrivialTypeSourceInfo(BaseSpec->getType(),
4600 SourceLocation()),
4601 BaseSpec->isVirtual(),
4602 SourceLocation(),
4603 BaseInit.getAs<Expr>(),
4604 SourceLocation(),
4605 SourceLocation());
4606
4607 return false;
4608}
4609
4610static bool RefersToRValueRef(Expr *MemRef) {
4611 ValueDecl *Referenced = cast<MemberExpr>(MemRef)->getMemberDecl();
4612 return Referenced->getType()->isRValueReferenceType();
4613}
4614
4615static bool
4616BuildImplicitMemberInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4617 ImplicitInitializerKind ImplicitInitKind,
4618 FieldDecl *Field, IndirectFieldDecl *Indirect,
4619 CXXCtorInitializer *&CXXMemberInit) {
4620 if (Field->isInvalidDecl())
4621 return true;
4622
4623 SourceLocation Loc = Constructor->getLocation();
4624
4625 if (ImplicitInitKind == IIK_Copy || ImplicitInitKind == IIK_Move) {
4626 bool Moving = ImplicitInitKind == IIK_Move;
4627 ParmVarDecl *Param = Constructor->getParamDecl(0);
4628 QualType ParamType = Param->getType().getNonReferenceType();
4629
4630 // Suppress copying zero-width bitfields.
4631 if (Field->isZeroLengthBitField(SemaRef.Context))
4632 return false;
4633
4634 Expr *MemberExprBase =
4635 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4636 SourceLocation(), Param, false,
4637 Loc, ParamType, VK_LValue, nullptr);
4638
4639 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(MemberExprBase));
4640
4641 if (Moving) {
4642 MemberExprBase = CastForMoving(SemaRef, MemberExprBase);
4643 }
4644
4645 // Build a reference to this field within the parameter.
4646 CXXScopeSpec SS;
4647 LookupResult MemberLookup(SemaRef, Field->getDeclName(), Loc,
4648 Sema::LookupMemberName);
4649 MemberLookup.addDecl(Indirect ? cast<ValueDecl>(Indirect)
4650 : cast<ValueDecl>(Field), AS_public);
4651 MemberLookup.resolveKind();
4652 ExprResult CtorArg
4653 = SemaRef.BuildMemberReferenceExpr(MemberExprBase,
4654 ParamType, Loc,
4655 /*IsArrow=*/false,
4656 SS,
4657 /*TemplateKWLoc=*/SourceLocation(),
4658 /*FirstQualifierInScope=*/nullptr,
4659 MemberLookup,
4660 /*TemplateArgs=*/nullptr,
4661 /*S*/nullptr);
4662 if (CtorArg.isInvalid())
4663 return true;
4664
4665 // C++11 [class.copy]p15:
4666 // - if a member m has rvalue reference type T&&, it is direct-initialized
4667 // with static_cast<T&&>(x.m);
4668 if (RefersToRValueRef(CtorArg.get())) {
4669 CtorArg = CastForMoving(SemaRef, CtorArg.get());
4670 }
4671
4672 InitializedEntity Entity =
4673 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4674 /*Implicit*/ true)
4675 : InitializedEntity::InitializeMember(Field, nullptr,
4676 /*Implicit*/ true);
4677
4678 // Direct-initialize to use the copy constructor.
4679 InitializationKind InitKind =
4680 InitializationKind::CreateDirect(Loc, SourceLocation(), SourceLocation());
4681
4682 Expr *CtorArgE = CtorArg.getAs<Expr>();
4683 InitializationSequence InitSeq(SemaRef, Entity, InitKind, CtorArgE);
4684 ExprResult MemberInit =
4685 InitSeq.Perform(SemaRef, Entity, InitKind, MultiExprArg(&CtorArgE, 1));
4686 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4687 if (MemberInit.isInvalid())
4688 return true;
4689
4690 if (Indirect)
4691 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4692 SemaRef.Context, Indirect, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4693 else
4694 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4695 SemaRef.Context, Field, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4696 return false;
4697 }
4698
4699 assert((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) &&(((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit
) && "Unhandled implicit init kind!") ? static_cast<
void> (0) : __assert_fail ("(ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) && \"Unhandled implicit init kind!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 4700, __PRETTY_FUNCTION__))
4700 "Unhandled implicit init kind!")(((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit
) && "Unhandled implicit init kind!") ? static_cast<
void> (0) : __assert_fail ("(ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) && \"Unhandled implicit init kind!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 4700, __PRETTY_FUNCTION__))
;
4701
4702 QualType FieldBaseElementType =
4703 SemaRef.Context.getBaseElementType(Field->getType());
4704
4705 if (FieldBaseElementType->isRecordType()) {
4706 InitializedEntity InitEntity =
4707 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4708 /*Implicit*/ true)
4709 : InitializedEntity::InitializeMember(Field, nullptr,
4710 /*Implicit*/ true);
4711 InitializationKind InitKind =
4712 InitializationKind::CreateDefault(Loc);
4713
4714 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4715 ExprResult MemberInit =
4716 InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4717
4718 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4719 if (MemberInit.isInvalid())
4720 return true;
4721
4722 if (Indirect)
4723 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4724 Indirect, Loc,
4725 Loc,
4726 MemberInit.get(),
4727 Loc);
4728 else
4729 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4730 Field, Loc, Loc,
4731 MemberInit.get(),
4732 Loc);
4733 return false;
4734 }
4735
4736 if (!Field->getParent()->isUnion()) {
4737 if (FieldBaseElementType->isReferenceType()) {
4738 SemaRef.Diag(Constructor->getLocation(),
4739 diag::err_uninitialized_member_in_ctor)
4740 << (int)Constructor->isImplicit()
4741 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4742 << 0 << Field->getDeclName();
4743 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4744 return true;
4745 }
4746
4747 if (FieldBaseElementType.isConstQualified()) {
4748 SemaRef.Diag(Constructor->getLocation(),
4749 diag::err_uninitialized_member_in_ctor)
4750 << (int)Constructor->isImplicit()
4751 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4752 << 1 << Field->getDeclName();
4753 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4754 return true;
4755 }
4756 }
4757
4758 if (FieldBaseElementType.hasNonTrivialObjCLifetime()) {
4759 // ARC and Weak:
4760 // Default-initialize Objective-C pointers to NULL.
4761 CXXMemberInit
4762 = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
4763 Loc, Loc,
4764 new (SemaRef.Context) ImplicitValueInitExpr(Field->getType()),
4765 Loc);
4766 return false;
4767 }
4768
4769 // Nothing to initialize.
4770 CXXMemberInit = nullptr;
4771 return false;
4772}
4773
4774namespace {
4775struct BaseAndFieldInfo {
4776 Sema &S;
4777 CXXConstructorDecl *Ctor;
4778 bool AnyErrorsInInits;
4779 ImplicitInitializerKind IIK;
4780 llvm::DenseMap<const void *, CXXCtorInitializer*> AllBaseFields;
4781 SmallVector<CXXCtorInitializer*, 8> AllToInit;
4782 llvm::DenseMap<TagDecl*, FieldDecl*> ActiveUnionMember;
4783
4784 BaseAndFieldInfo(Sema &S, CXXConstructorDecl *Ctor, bool ErrorsInInits)
4785 : S(S), Ctor(Ctor), AnyErrorsInInits(ErrorsInInits) {
4786 bool Generated = Ctor->isImplicit() || Ctor->isDefaulted();
4787 if (Ctor->getInheritedConstructor())
4788 IIK = IIK_Inherit;
4789 else if (Generated && Ctor->isCopyConstructor())
4790 IIK = IIK_Copy;
4791 else if (Generated && Ctor->isMoveConstructor())
4792 IIK = IIK_Move;
4793 else
4794 IIK = IIK_Default;
4795 }
4796
4797 bool isImplicitCopyOrMove() const {
4798 switch (IIK) {
4799 case IIK_Copy:
4800 case IIK_Move:
4801 return true;
4802
4803 case IIK_Default:
4804 case IIK_Inherit:
4805 return false;
4806 }
4807
4808 llvm_unreachable("Invalid ImplicitInitializerKind!")::llvm::llvm_unreachable_internal("Invalid ImplicitInitializerKind!"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 4808)
;
4809 }
4810
4811 bool addFieldInitializer(CXXCtorInitializer *Init) {
4812 AllToInit.push_back(Init);
4813
4814 // Check whether this initializer makes the field "used".
4815 if (Init->getInit()->HasSideEffects(S.Context))
4816 S.UnusedPrivateFields.remove(Init->getAnyMember());
4817
4818 return false;
4819 }
4820
4821 bool isInactiveUnionMember(FieldDecl *Field) {
4822 RecordDecl *Record = Field->getParent();
4823 if (!Record->isUnion())
4824 return false;
4825
4826 if (FieldDecl *Active =
4827 ActiveUnionMember.lookup(Record->getCanonicalDecl()))
4828 return Active != Field->getCanonicalDecl();
4829
4830 // In an implicit copy or move constructor, ignore any in-class initializer.
4831 if (isImplicitCopyOrMove())
4832 return true;
4833
4834 // If there's no explicit initialization, the field is active only if it
4835 // has an in-class initializer...
4836 if (Field->hasInClassInitializer())
4837 return false;
4838 // ... or it's an anonymous struct or union whose class has an in-class
4839 // initializer.
4840 if (!Field->isAnonymousStructOrUnion())
4841 return true;
4842 CXXRecordDecl *FieldRD = Field->getType()->getAsCXXRecordDecl();
4843 return !FieldRD->hasInClassInitializer();
4844 }
4845
4846 /// Determine whether the given field is, or is within, a union member
4847 /// that is inactive (because there was an initializer given for a different
4848 /// member of the union, or because the union was not initialized at all).
4849 bool isWithinInactiveUnionMember(FieldDecl *Field,
4850 IndirectFieldDecl *Indirect) {
4851 if (!Indirect)
4852 return isInactiveUnionMember(Field);
4853
4854 for (auto *C : Indirect->chain()) {
4855 FieldDecl *Field = dyn_cast<FieldDecl>(C);
4856 if (Field && isInactiveUnionMember(Field))
4857 return true;
4858 }
4859 return false;
4860 }
4861};
4862}
4863
4864/// Determine whether the given type is an incomplete or zero-lenfgth
4865/// array type.
4866static bool isIncompleteOrZeroLengthArrayType(ASTContext &Context, QualType T) {
4867 if (T->isIncompleteArrayType())
4868 return true;
4869
4870 while (const ConstantArrayType *ArrayT = Context.getAsConstantArrayType(T)) {
4871 if (!ArrayT->getSize())
4872 return true;
4873
4874 T = ArrayT->getElementType();
4875 }
4876
4877 return false;
4878}
4879
4880static bool CollectFieldInitializer(Sema &SemaRef, BaseAndFieldInfo &Info,
4881 FieldDecl *Field,
4882 IndirectFieldDecl *Indirect = nullptr) {
4883 if (Field->isInvalidDecl())
4884 return false;
4885
4886 // Overwhelmingly common case: we have a direct initializer for this field.
4887 if (CXXCtorInitializer *Init =
4888 Info.AllBaseFields.lookup(Field->getCanonicalDecl()))
4889 return Info.addFieldInitializer(Init);
4890
4891 // C++11 [class.base.init]p8:
4892 // if the entity is a non-static data member that has a
4893 // brace-or-equal-initializer and either
4894 // -- the constructor's class is a union and no other variant member of that
4895 // union is designated by a mem-initializer-id or
4896 // -- the constructor's class is not a union, and, if the entity is a member
4897 // of an anonymous union, no other member of that union is designated by
4898 // a mem-initializer-id,
4899 // the entity is initialized as specified in [dcl.init].
4900 //
4901 // We also apply the same rules to handle anonymous structs within anonymous
4902 // unions.
4903 if (Info.isWithinInactiveUnionMember(Field, Indirect))
4904 return false;
4905
4906 if (Field->hasInClassInitializer() && !Info.isImplicitCopyOrMove()) {
4907 ExprResult DIE =
4908 SemaRef.BuildCXXDefaultInitExpr(Info.Ctor->getLocation(), Field);
4909 if (DIE.isInvalid())
4910 return true;
4911
4912 auto Entity = InitializedEntity::InitializeMember(Field, nullptr, true);
4913 SemaRef.checkInitializerLifetime(Entity, DIE.get());
4914
4915 CXXCtorInitializer *Init;
4916 if (Indirect)
4917 Init = new (SemaRef.Context)
4918 CXXCtorInitializer(SemaRef.Context, Indirect, SourceLocation(),
4919 SourceLocation(), DIE.get(), SourceLocation());
4920 else
4921 Init = new (SemaRef.Context)
4922 CXXCtorInitializer(SemaRef.Context, Field, SourceLocation(),
4923 SourceLocation(), DIE.get(), SourceLocation());
4924 return Info.addFieldInitializer(Init);
4925 }
4926
4927 // Don't initialize incomplete or zero-length arrays.
4928 if (isIncompleteOrZeroLengthArrayType(SemaRef.Context, Field->getType()))
4929 return false;
4930
4931 // Don't try to build an implicit initializer if there were semantic
4932 // errors in any of the initializers (and therefore we might be
4933 // missing some that the user actually wrote).
4934 if (Info.AnyErrorsInInits)
4935 return false;
4936
4937 CXXCtorInitializer *Init = nullptr;
4938 if (BuildImplicitMemberInitializer(Info.S, Info.Ctor, Info.IIK, Field,
4939 Indirect, Init))
4940 return true;
4941
4942 if (!Init)
4943 return false;
4944
4945 return Info.addFieldInitializer(Init);
4946}
4947
4948bool
4949Sema::SetDelegatingInitializer(CXXConstructorDecl *Constructor,
4950 CXXCtorInitializer *Initializer) {
4951 assert(Initializer->isDelegatingInitializer())((Initializer->isDelegatingInitializer()) ? static_cast<
void> (0) : __assert_fail ("Initializer->isDelegatingInitializer()"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 4951, __PRETTY_FUNCTION__))
;
4952 Constructor->setNumCtorInitializers(1);
4953 CXXCtorInitializer **initializer =
4954 new (Context) CXXCtorInitializer*[1];
4955 memcpy(initializer, &Initializer, sizeof (CXXCtorInitializer*));
4956 Constructor->setCtorInitializers(initializer);
4957
4958 if (CXXDestructorDecl *Dtor = LookupDestructor(Constructor->getParent())) {
4959 MarkFunctionReferenced(Initializer->getSourceLocation(), Dtor);
4960 DiagnoseUseOfDecl(Dtor, Initializer->getSourceLocation());
4961 }
4962
4963 DelegatingCtorDecls.push_back(Constructor);
4964
4965 DiagnoseUninitializedFields(*this, Constructor);
4966
4967 return false;
4968}
4969
4970bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
4971 ArrayRef<CXXCtorInitializer *> Initializers) {
4972 if (Constructor->isDependentContext()) {
4973 // Just store the initializers as written, they will be checked during
4974 // instantiation.
4975 if (!Initializers.empty()) {
4976 Constructor->setNumCtorInitializers(Initializers.size());
4977 CXXCtorInitializer **baseOrMemberInitializers =
4978 new (Context) CXXCtorInitializer*[Initializers.size()];
4979 memcpy(baseOrMemberInitializers, Initializers.data(),
4980 Initializers.size() * sizeof(CXXCtorInitializer*));
4981 Constructor->setCtorInitializers(baseOrMemberInitializers);
4982 }
4983
4984 // Let template instantiation know whether we had errors.
4985 if (AnyErrors)
4986 Constructor->setInvalidDecl();
4987
4988 return false;
4989 }
4990
4991 BaseAndFieldInfo Info(*this, Constructor, AnyErrors);
4992
4993 // We need to build the initializer AST according to order of construction
4994 // and not what user specified in the Initializers list.
4995 CXXRecordDecl *ClassDecl = Constructor->getParent()->getDefinition();
4996 if (!ClassDecl)
4997 return true;
4998
4999 bool HadError = false;
5000
5001 for (unsigned i = 0; i < Initializers.size(); i++) {
5002 CXXCtorInitializer *Member = Initializers[i];
5003
5004 if (Member->isBaseInitializer())
5005 Info.AllBaseFields[Member->getBaseClass()->getAs<RecordType>()] = Member;
5006 else {
5007 Info.AllBaseFields[Member->getAnyMember()->getCanonicalDecl()] = Member;
5008
5009 if (IndirectFieldDecl *F = Member->getIndirectMember()) {
5010 for (auto *C : F->chain()) {
5011 FieldDecl *FD = dyn_cast<FieldDecl>(C);
5012 if (FD && FD->getParent()->isUnion())
5013 Info.ActiveUnionMember.insert(std::make_pair(
5014 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
5015 }
5016 } else if (FieldDecl *FD = Member->getMember()) {
5017 if (FD->getParent()->isUnion())
5018 Info.ActiveUnionMember.insert(std::make_pair(
5019 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
5020 }
5021 }
5022 }
5023
5024 // Keep track of the direct virtual bases.
5025 llvm::SmallPtrSet<CXXBaseSpecifier *, 16> DirectVBases;
5026 for (auto &I : ClassDecl->bases()) {
5027 if (I.isVirtual())
5028 DirectVBases.insert(&I);
5029 }
5030
5031 // Push virtual bases before others.
5032 for (auto &VBase : ClassDecl->vbases()) {
5033 if (CXXCtorInitializer *Value
5034 = Info.AllBaseFields.lookup(VBase.getType()->getAs<RecordType>())) {
5035 // [class.base.init]p7, per DR257:
5036 // A mem-initializer where the mem-initializer-id names a virtual base
5037 // class is ignored during execution of a constructor of any class that
5038 // is not the most derived class.
5039 if (ClassDecl->isAbstract()) {
5040 // FIXME: Provide a fixit to remove the base specifier. This requires
5041 // tracking the location of the associated comma for a base specifier.
5042 Diag(Value->getSourceLocation(), diag::warn_abstract_vbase_init_ignored)
5043 << VBase.getType() << ClassDecl;
5044 DiagnoseAbstractType(ClassDecl);
5045 }
5046
5047 Info.AllToInit.push_back(Value);
5048 } else if (!AnyErrors && !ClassDecl->isAbstract()) {
5049 // [class.base.init]p8, per DR257:
5050 // If a given [...] base class is not named by a mem-initializer-id
5051 // [...] and the entity is not a virtual base class of an abstract
5052 // class, then [...] the entity is default-initialized.
5053 bool IsInheritedVirtualBase = !DirectVBases.count(&VBase);
5054 CXXCtorInitializer *CXXBaseInit;
5055 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
5056 &VBase, IsInheritedVirtualBase,
5057 CXXBaseInit)) {
5058 HadError = true;
5059 continue;
5060 }
5061
5062 Info.AllToInit.push_back(CXXBaseInit);
5063 }
5064 }
5065
5066 // Non-virtual bases.
5067 for (auto &Base : ClassDecl->bases()) {
5068 // Virtuals are in the virtual base list and already constructed.
5069 if (Base.isVirtual())
5070 continue;
5071
5072 if (CXXCtorInitializer *Value
5073 = Info.AllBaseFields.lookup(Base.getType()->getAs<RecordType>())) {
5074 Info.AllToInit.push_back(Value);
5075 } else if (!AnyErrors) {
5076 CXXCtorInitializer *CXXBaseInit;
5077 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
5078 &Base, /*IsInheritedVirtualBase=*/false,
5079 CXXBaseInit)) {
5080 HadError = true;
5081 continue;
5082 }
5083
5084 Info.AllToInit.push_back(CXXBaseInit);
5085 }
5086 }
5087
5088 // Fields.
5089 for (auto *Mem : ClassDecl->decls()) {
5090 if (auto *F = dyn_cast<FieldDecl>(Mem)) {
5091 // C++ [class.bit]p2:
5092 // A declaration for a bit-field that omits the identifier declares an
5093 // unnamed bit-field. Unnamed bit-fields are not members and cannot be
5094 // initialized.
5095 if (F->isUnnamedBitfield())
5096 continue;
5097
5098 // If we're not generating the implicit copy/move constructor, then we'll
5099 // handle anonymous struct/union fields based on their individual
5100 // indirect fields.
5101 if (F->isAnonymousStructOrUnion() && !Info.isImplicitCopyOrMove())
5102 continue;
5103
5104 if (CollectFieldInitializer(*this, Info, F))
5105 HadError = true;
5106 continue;
5107 }
5108
5109 // Beyond this point, we only consider default initialization.
5110 if (Info.isImplicitCopyOrMove())
5111 continue;
5112
5113 if (auto *F = dyn_cast<IndirectFieldDecl>(Mem)) {
5114 if (F->getType()->isIncompleteArrayType()) {
5115 assert(ClassDecl->hasFlexibleArrayMember() &&((ClassDecl->hasFlexibleArrayMember() && "Incomplete array type is not valid"
) ? static_cast<void> (0) : __assert_fail ("ClassDecl->hasFlexibleArrayMember() && \"Incomplete array type is not valid\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5116, __PRETTY_FUNCTION__))
5116 "Incomplete array type is not valid")((ClassDecl->hasFlexibleArrayMember() && "Incomplete array type is not valid"
) ? static_cast<void> (0) : __assert_fail ("ClassDecl->hasFlexibleArrayMember() && \"Incomplete array type is not valid\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5116, __PRETTY_FUNCTION__))
;
5117 continue;
5118 }
5119
5120 // Initialize each field of an anonymous struct individually.
5121 if (CollectFieldInitializer(*this, Info, F->getAnonField(), F))
5122 HadError = true;
5123
5124 continue;
5125 }
5126 }
5127
5128 unsigned NumInitializers = Info.AllToInit.size();
5129 if (NumInitializers > 0) {
5130 Constructor->setNumCtorInitializers(NumInitializers);
5131 CXXCtorInitializer **baseOrMemberInitializers =
5132 new (Context) CXXCtorInitializer*[NumInitializers];
5133 memcpy(baseOrMemberInitializers, Info.AllToInit.data(),
5134 NumInitializers * sizeof(CXXCtorInitializer*));
5135 Constructor->setCtorInitializers(baseOrMemberInitializers);
5136
5137 // Constructors implicitly reference the base and member
5138 // destructors.
5139 MarkBaseAndMemberDestructorsReferenced(Constructor->getLocation(),
5140 Constructor->getParent());
5141 }
5142
5143 return HadError;
5144}
5145
5146static void PopulateKeysForFields(FieldDecl *Field, SmallVectorImpl<const void*> &IdealInits) {
5147 if (const RecordType *RT = Field->getType()->getAs<RecordType>()) {
5148 const RecordDecl *RD = RT->getDecl();
5149 if (RD->isAnonymousStructOrUnion()) {
5150 for (auto *Field : RD->fields())
5151 PopulateKeysForFields(Field, IdealInits);
5152 return;
5153 }
5154 }
5155 IdealInits.push_back(Field->getCanonicalDecl());
5156}
5157
5158static const void *GetKeyForBase(ASTContext &Context, QualType BaseType) {
5159 return Context.getCanonicalType(BaseType).getTypePtr();
5160}
5161
5162static const void *GetKeyForMember(ASTContext &Context,
5163 CXXCtorInitializer *Member) {
5164 if (!Member->isAnyMemberInitializer())
5165 return GetKeyForBase(Context, QualType(Member->getBaseClass(), 0));
5166
5167 return Member->getAnyMember()->getCanonicalDecl();
5168}
5169
5170static void DiagnoseBaseOrMemInitializerOrder(
5171 Sema &SemaRef, const CXXConstructorDecl *Constructor,
5172 ArrayRef<CXXCtorInitializer *> Inits) {
5173 if (Constructor->getDeclContext()->isDependentContext())
5174 return;
5175
5176 // Don't check initializers order unless the warning is enabled at the
5177 // location of at least one initializer.
5178 bool ShouldCheckOrder = false;
5179 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
5180 CXXCtorInitializer *Init = Inits[InitIndex];
5181 if (!SemaRef.Diags.isIgnored(diag::warn_initializer_out_of_order,
5182 Init->getSourceLocation())) {
5183 ShouldCheckOrder = true;
5184 break;
5185 }
5186 }
5187 if (!ShouldCheckOrder)
5188 return;
5189
5190 // Build the list of bases and members in the order that they'll
5191 // actually be initialized. The explicit initializers should be in
5192 // this same order but may be missing things.
5193 SmallVector<const void*, 32> IdealInitKeys;
5194
5195 const CXXRecordDecl *ClassDecl = Constructor->getParent();
5196
5197 // 1. Virtual bases.
5198 for (const auto &VBase : ClassDecl->vbases())
5199 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, VBase.getType()));
5200
5201 // 2. Non-virtual bases.
5202 for (const auto &Base : ClassDecl->bases()) {
5203 if (Base.isVirtual())
5204 continue;
5205 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, Base.getType()));
5206 }
5207
5208 // 3. Direct fields.
5209 for (auto *Field : ClassDecl->fields()) {
5210 if (Field->isUnnamedBitfield())
5211 continue;
5212
5213 PopulateKeysForFields(Field, IdealInitKeys);
5214 }
5215
5216 unsigned NumIdealInits = IdealInitKeys.size();
5217 unsigned IdealIndex = 0;
5218
5219 CXXCtorInitializer *PrevInit = nullptr;
5220 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
5221 CXXCtorInitializer *Init = Inits[InitIndex];
5222 const void *InitKey = GetKeyForMember(SemaRef.Context, Init);
5223
5224 // Scan forward to try to find this initializer in the idealized
5225 // initializers list.
5226 for (; IdealIndex != NumIdealInits; ++IdealIndex)
5227 if (InitKey == IdealInitKeys[IdealIndex])
5228 break;
5229
5230 // If we didn't find this initializer, it must be because we
5231 // scanned past it on a previous iteration. That can only
5232 // happen if we're out of order; emit a warning.
5233 if (IdealIndex == NumIdealInits && PrevInit) {
5234 Sema::SemaDiagnosticBuilder D =
5235 SemaRef.Diag(PrevInit->getSourceLocation(),
5236 diag::warn_initializer_out_of_order);
5237
5238 if (PrevInit->isAnyMemberInitializer())
5239 D << 0 << PrevInit->getAnyMember()->getDeclName();
5240 else
5241 D << 1 << PrevInit->getTypeSourceInfo()->getType();
5242
5243 if (Init->isAnyMemberInitializer())
5244 D << 0 << Init->getAnyMember()->getDeclName();
5245 else
5246 D << 1 << Init->getTypeSourceInfo()->getType();
5247
5248 // Move back to the initializer's location in the ideal list.
5249 for (IdealIndex = 0; IdealIndex != NumIdealInits; ++IdealIndex)
5250 if (InitKey == IdealInitKeys[IdealIndex])
5251 break;
5252
5253 assert(IdealIndex < NumIdealInits &&((IdealIndex < NumIdealInits && "initializer not found in initializer list"
) ? static_cast<void> (0) : __assert_fail ("IdealIndex < NumIdealInits && \"initializer not found in initializer list\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5254, __PRETTY_FUNCTION__))
5254 "initializer not found in initializer list")((IdealIndex < NumIdealInits && "initializer not found in initializer list"
) ? static_cast<void> (0) : __assert_fail ("IdealIndex < NumIdealInits && \"initializer not found in initializer list\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5254, __PRETTY_FUNCTION__))
;
5255 }
5256
5257 PrevInit = Init;
5258 }
5259}
5260
5261namespace {
5262bool CheckRedundantInit(Sema &S,
5263 CXXCtorInitializer *Init,
5264 CXXCtorInitializer *&PrevInit) {
5265 if (!PrevInit) {
5266 PrevInit = Init;
5267 return false;
5268 }
5269
5270 if (FieldDecl *Field = Init->getAnyMember())
5271 S.Diag(Init->getSourceLocation(),
5272 diag::err_multiple_mem_initialization)
5273 << Field->getDeclName()
5274 << Init->getSourceRange();
5275 else {
5276 const Type *BaseClass = Init->getBaseClass();
5277 assert(BaseClass && "neither field nor base")((BaseClass && "neither field nor base") ? static_cast
<void> (0) : __assert_fail ("BaseClass && \"neither field nor base\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5277, __PRETTY_FUNCTION__))
;
5278 S.Diag(Init->getSourceLocation(),
5279 diag::err_multiple_base_initialization)
5280 << QualType(BaseClass, 0)
5281 << Init->getSourceRange();
5282 }
5283 S.Diag(PrevInit->getSourceLocation(), diag::note_previous_initializer)
5284 << 0 << PrevInit->getSourceRange();
5285
5286 return true;
5287}
5288
5289typedef std::pair<NamedDecl *, CXXCtorInitializer *> UnionEntry;
5290typedef llvm::DenseMap<RecordDecl*, UnionEntry> RedundantUnionMap;
5291
5292bool CheckRedundantUnionInit(Sema &S,
5293 CXXCtorInitializer *Init,
5294 RedundantUnionMap &Unions) {
5295 FieldDecl *Field = Init->getAnyMember();
5296 RecordDecl *Parent = Field->getParent();
5297 NamedDecl *Child = Field;
5298
5299 while (Parent->isAnonymousStructOrUnion() || Parent->isUnion()) {
5300 if (Parent->isUnion()) {
5301 UnionEntry &En = Unions[Parent];
5302 if (En.first && En.first != Child) {
5303 S.Diag(Init->getSourceLocation(),
5304 diag::err_multiple_mem_union_initialization)
5305 << Field->getDeclName()
5306 << Init->getSourceRange();
5307 S.Diag(En.second->getSourceLocation(), diag::note_previous_initializer)
5308 << 0 << En.second->getSourceRange();
5309 return true;
5310 }
5311 if (!En.first) {
5312 En.first = Child;
5313 En.second = Init;
5314 }
5315 if (!Parent->isAnonymousStructOrUnion())
5316 return false;
5317 }
5318
5319 Child = Parent;
5320 Parent = cast<RecordDecl>(Parent->getDeclContext());
5321 }
5322
5323 return false;
5324}
5325}
5326
5327/// ActOnMemInitializers - Handle the member initializers for a constructor.
5328void Sema::ActOnMemInitializers(Decl *ConstructorDecl,
5329 SourceLocation ColonLoc,
5330 ArrayRef<CXXCtorInitializer*> MemInits,
5331 bool AnyErrors) {
5332 if (!ConstructorDecl)
5333 return;
5334
5335 AdjustDeclIfTemplate(ConstructorDecl);
5336
5337 CXXConstructorDecl *Constructor
5338 = dyn_cast<CXXConstructorDecl>(ConstructorDecl);
5339
5340 if (!Constructor) {
5341 Diag(ColonLoc, diag::err_only_constructors_take_base_inits);
5342 return;
5343 }
5344
5345 // Mapping for the duplicate initializers check.
5346 // For member initializers, this is keyed with a FieldDecl*.
5347 // For base initializers, this is keyed with a Type*.
5348 llvm::DenseMap<const void *, CXXCtorInitializer *> Members;
5349
5350 // Mapping for the inconsistent anonymous-union initializers check.
5351 RedundantUnionMap MemberUnions;
5352
5353 bool HadError = false;
5354 for (unsigned i = 0; i < MemInits.size(); i++) {
5355 CXXCtorInitializer *Init = MemInits[i];
5356
5357 // Set the source order index.
5358 Init->setSourceOrder(i);
5359
5360 if (Init->isAnyMemberInitializer()) {
5361 const void *Key = GetKeyForMember(Context, Init);
5362 if (CheckRedundantInit(*this, Init, Members[Key]) ||
5363 CheckRedundantUnionInit(*this, Init, MemberUnions))
5364 HadError = true;
5365 } else if (Init->isBaseInitializer()) {
5366 const void *Key = GetKeyForMember(Context, Init);
5367 if (CheckRedundantInit(*this, Init, Members[Key]))
5368 HadError = true;
5369 } else {
5370 assert(Init->isDelegatingInitializer())((Init->isDelegatingInitializer()) ? static_cast<void>
(0) : __assert_fail ("Init->isDelegatingInitializer()", "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5370, __PRETTY_FUNCTION__))
;
5371 // This must be the only initializer
5372 if (MemInits.size() != 1) {
5373 Diag(Init->getSourceLocation(),
5374 diag::err_delegating_initializer_alone)
5375 << Init->getSourceRange() << MemInits[i ? 0 : 1]->getSourceRange();
5376 // We will treat this as being the only initializer.
5377 }
5378 SetDelegatingInitializer(Constructor, MemInits[i]);
5379 // Return immediately as the initializer is set.
5380 return;
5381 }
5382 }
5383
5384 if (HadError)
5385 return;
5386
5387 DiagnoseBaseOrMemInitializerOrder(*this, Constructor, MemInits);
5388
5389 SetCtorInitializers(Constructor, AnyErrors, MemInits);
5390
5391 DiagnoseUninitializedFields(*this, Constructor);
5392}
5393
5394void
5395Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
5396 CXXRecordDecl *ClassDecl) {
5397 // Ignore dependent contexts. Also ignore unions, since their members never
5398 // have destructors implicitly called.
5399 if (ClassDecl->isDependentContext() || ClassDecl->isUnion())
5400 return;
5401
5402 // FIXME: all the access-control diagnostics are positioned on the
5403 // field/base declaration. That's probably good; that said, the
5404 // user might reasonably want to know why the destructor is being
5405 // emitted, and we currently don't say.
5406
5407 // Non-static data members.
5408 for (auto *Field : ClassDecl->fields()) {
5409 if (Field->isInvalidDecl())
5410 continue;
5411
5412 // Don't destroy incomplete or zero-length arrays.
5413 if (isIncompleteOrZeroLengthArrayType(Context, Field->getType()))
5414 continue;
5415
5416 QualType FieldType = Context.getBaseElementType(Field->getType());
5417
5418 const RecordType* RT = FieldType->getAs<RecordType>();
5419 if (!RT)
5420 continue;
5421
5422 CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5423 if (FieldClassDecl->isInvalidDecl())
5424 continue;
5425 if (FieldClassDecl->hasIrrelevantDestructor())
5426 continue;
5427 // The destructor for an implicit anonymous union member is never invoked.
5428 if (FieldClassDecl->isUnion() && FieldClassDecl->isAnonymousStructOrUnion())
5429 continue;
5430
5431 CXXDestructorDecl *Dtor = LookupDestructor(FieldClassDecl);
5432 assert(Dtor && "No dtor found for FieldClassDecl!")((Dtor && "No dtor found for FieldClassDecl!") ? static_cast
<void> (0) : __assert_fail ("Dtor && \"No dtor found for FieldClassDecl!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5432, __PRETTY_FUNCTION__))
;
5433 CheckDestructorAccess(Field->getLocation(), Dtor,
5434 PDiag(diag::err_access_dtor_field)
5435 << Field->getDeclName()
5436 << FieldType);
5437
5438 MarkFunctionReferenced(Location, Dtor);
5439 DiagnoseUseOfDecl(Dtor, Location);
5440 }
5441
5442 // We only potentially invoke the destructors of potentially constructed
5443 // subobjects.
5444 bool VisitVirtualBases = !ClassDecl->isAbstract();
5445
5446 llvm::SmallPtrSet<const RecordType *, 8> DirectVirtualBases;
5447
5448 // Bases.
5449 for (const auto &Base : ClassDecl->bases()) {
5450 // Bases are always records in a well-formed non-dependent class.
5451 const RecordType *RT = Base.getType()->getAs<RecordType>();
5452
5453 // Remember direct virtual bases.
5454 if (Base.isVirtual()) {
5455 if (!VisitVirtualBases)
5456 continue;
5457 DirectVirtualBases.insert(RT);
5458 }
5459
5460 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5461 // If our base class is invalid, we probably can't get its dtor anyway.
5462 if (BaseClassDecl->isInvalidDecl())
5463 continue;
5464 if (BaseClassDecl->hasIrrelevantDestructor())
5465 continue;
5466
5467 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5468 assert(Dtor && "No dtor found for BaseClassDecl!")((Dtor && "No dtor found for BaseClassDecl!") ? static_cast
<void> (0) : __assert_fail ("Dtor && \"No dtor found for BaseClassDecl!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5468, __PRETTY_FUNCTION__))
;
5469
5470 // FIXME: caret should be on the start of the class name
5471 CheckDestructorAccess(Base.getBeginLoc(), Dtor,
5472 PDiag(diag::err_access_dtor_base)
5473 << Base.getType() << Base.getSourceRange(),
5474 Context.getTypeDeclType(ClassDecl));
5475
5476 MarkFunctionReferenced(Location, Dtor);
5477 DiagnoseUseOfDecl(Dtor, Location);
5478 }
5479
5480 if (!VisitVirtualBases)
5481 return;
5482
5483 // Virtual bases.
5484 for (const auto &VBase : ClassDecl->vbases()) {
5485 // Bases are always records in a well-formed non-dependent class.
5486 const RecordType *RT = VBase.getType()->castAs<RecordType>();
5487
5488 // Ignore direct virtual bases.
5489 if (DirectVirtualBases.count(RT))
5490 continue;
5491
5492 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5493 // If our base class is invalid, we probably can't get its dtor anyway.
5494 if (BaseClassDecl->isInvalidDecl())
5495 continue;
5496 if (BaseClassDecl->hasIrrelevantDestructor())
5497 continue;
5498
5499 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5500 assert(Dtor && "No dtor found for BaseClassDecl!")((Dtor && "No dtor found for BaseClassDecl!") ? static_cast
<void> (0) : __assert_fail ("Dtor && \"No dtor found for BaseClassDecl!\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5500, __PRETTY_FUNCTION__))
;
5501 if (CheckDestructorAccess(
5502 ClassDecl->getLocation(), Dtor,
5503 PDiag(diag::err_access_dtor_vbase)
5504 << Context.getTypeDeclType(ClassDecl) << VBase.getType(),
5505 Context.getTypeDeclType(ClassDecl)) ==
5506 AR_accessible) {
5507 CheckDerivedToBaseConversion(
5508 Context.getTypeDeclType(ClassDecl), VBase.getType(),
5509 diag::err_access_dtor_vbase, 0, ClassDecl->getLocation(),
5510 SourceRange(), DeclarationName(), nullptr);
5511 }
5512
5513 MarkFunctionReferenced(Location, Dtor);
5514 DiagnoseUseOfDecl(Dtor, Location);
5515 }
5516}
5517
5518void Sema::ActOnDefaultCtorInitializers(Decl *CDtorDecl) {
5519 if (!CDtorDecl)
5520 return;
5521
5522 if (CXXConstructorDecl *Constructor
5523 = dyn_cast<CXXConstructorDecl>(CDtorDecl)) {
5524 SetCtorInitializers(Constructor, /*AnyErrors=*/false);
5525 DiagnoseUninitializedFields(*this, Constructor);
5526 }
5527}
5528
5529bool Sema::isAbstractType(SourceLocation Loc, QualType T) {
5530 if (!getLangOpts().CPlusPlus)
5531 return false;
5532
5533 const auto *RD = Context.getBaseElementType(T)->getAsCXXRecordDecl();
5534 if (!RD)
5535 return false;
5536
5537 // FIXME: Per [temp.inst]p1, we are supposed to trigger instantiation of a
5538 // class template specialization here, but doing so breaks a lot of code.
5539
5540 // We can't answer whether something is abstract until it has a
5541 // definition. If it's currently being defined, we'll walk back
5542 // over all the declarations when we have a full definition.
5543 const CXXRecordDecl *Def = RD->getDefinition();
5544 if (!Def || Def->isBeingDefined())
5545 return false;
5546
5547 return RD->isAbstract();
5548}
5549
5550bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T,
5551 TypeDiagnoser &Diagnoser) {
5552 if (!isAbstractType(Loc, T))
5553 return false;
5554
5555 T = Context.getBaseElementType(T);
5556 Diagnoser.diagnose(*this, Loc, T);
5557 DiagnoseAbstractType(T->getAsCXXRecordDecl());
5558 return true;
5559}
5560
5561void Sema::DiagnoseAbstractType(const CXXRecordDecl *RD) {
5562 // Check if we've already emitted the list of pure virtual functions
5563 // for this class.
5564 if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD))
5565 return;
5566
5567 // If the diagnostic is suppressed, don't emit the notes. We're only
5568 // going to emit them once, so try to attach them to a diagnostic we're
5569 // actually going to show.
5570 if (Diags.isLastDiagnosticIgnored())
5571 return;
5572
5573 CXXFinalOverriderMap FinalOverriders;
5574 RD->getFinalOverriders(FinalOverriders);
5575
5576 // Keep a set of seen pure methods so we won't diagnose the same method
5577 // more than once.
5578 llvm::SmallPtrSet<const CXXMethodDecl *, 8> SeenPureMethods;
5579
5580 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
5581 MEnd = FinalOverriders.end();
5582 M != MEnd;
5583 ++M) {
5584 for (OverridingMethods::iterator SO = M->second.begin(),
5585 SOEnd = M->second.end();
5586 SO != SOEnd; ++SO) {
5587 // C++ [class.abstract]p4:
5588 // A class is abstract if it contains or inherits at least one
5589 // pure virtual function for which the final overrider is pure
5590 // virtual.
5591
5592 //
5593 if (SO->second.size() != 1)
5594 continue;
5595
5596 if (!SO->second.front().Method->isPure())
5597 continue;
5598
5599 if (!SeenPureMethods.insert(SO->second.front().Method).second)
5600 continue;
5601
5602 Diag(SO->second.front().Method->getLocation(),
5603 diag::note_pure_virtual_function)
5604 << SO->second.front().Method->getDeclName() << RD->getDeclName();
5605 }
5606 }
5607
5608 if (!PureVirtualClassDiagSet)
5609 PureVirtualClassDiagSet.reset(new RecordDeclSetTy);
5610 PureVirtualClassDiagSet->insert(RD);
5611}
5612
5613namespace {
5614struct AbstractUsageInfo {
5615 Sema &S;
5616 CXXRecordDecl *Record;
5617 CanQualType AbstractType;
5618 bool Invalid;
5619
5620 AbstractUsageInfo(Sema &S, CXXRecordDecl *Record)
5621 : S(S), Record(Record),
5622 AbstractType(S.Context.getCanonicalType(
5623 S.Context.getTypeDeclType(Record))),
5624 Invalid(false) {}
5625
5626 void DiagnoseAbstractType() {
5627 if (Invalid) return;
5628 S.DiagnoseAbstractType(Record);
5629 Invalid = true;
5630 }
5631
5632 void CheckType(const NamedDecl *D, TypeLoc TL, Sema::AbstractDiagSelID Sel);
5633};
5634
5635struct CheckAbstractUsage {
5636 AbstractUsageInfo &Info;
5637 const NamedDecl *Ctx;
5638
5639 CheckAbstractUsage(AbstractUsageInfo &Info, const NamedDecl *Ctx)
5640 : Info(Info), Ctx(Ctx) {}
5641
5642 void Visit(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
5643 switch (TL.getTypeLocClass()) {
5644#define ABSTRACT_TYPELOC(CLASS, PARENT)
5645#define TYPELOC(CLASS, PARENT) \
5646 case TypeLoc::CLASS: Check(TL.castAs<CLASS##TypeLoc>(), Sel); break;
5647#include "clang/AST/TypeLocNodes.def"
5648 }
5649 }
5650
5651 void Check(FunctionProtoTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5652 Visit(TL.getReturnLoc(), Sema::AbstractReturnType);
5653 for (unsigned I = 0, E = TL.getNumParams(); I != E; ++I) {
5654 if (!TL.getParam(I))
5655 continue;
5656
5657 TypeSourceInfo *TSI = TL.getParam(I)->getTypeSourceInfo();
5658 if (TSI) Visit(TSI->getTypeLoc(), Sema::AbstractParamType);
5659 }
5660 }
5661
5662 void Check(ArrayTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5663 Visit(TL.getElementLoc(), Sema::AbstractArrayType);
5664 }
5665
5666 void Check(TemplateSpecializationTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5667 // Visit the type parameters from a permissive context.
5668 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) {
5669 TemplateArgumentLoc TAL = TL.getArgLoc(I);
5670 if (TAL.getArgument().getKind() == TemplateArgument::Type)
5671 if (TypeSourceInfo *TSI = TAL.getTypeSourceInfo())
5672 Visit(TSI->getTypeLoc(), Sema::AbstractNone);
5673 // TODO: other template argument types?
5674 }
5675 }
5676
5677 // Visit pointee types from a permissive context.
5678#define CheckPolymorphic(Type)void Check(Type TL, Sema::AbstractDiagSelID Sel) { Visit(TL.getNextTypeLoc
(), Sema::AbstractNone); }
\
5679 void Check(Type TL, Sema::AbstractDiagSelID Sel) { \
5680 Visit(TL.getNextTypeLoc(), Sema::AbstractNone); \
5681 }
5682 CheckPolymorphic(PointerTypeLoc)void Check(PointerTypeLoc TL, Sema::AbstractDiagSelID Sel) { Visit
(TL.getNextTypeLoc(), Sema::AbstractNone); }
5683 CheckPolymorphic(ReferenceTypeLoc)void Check(ReferenceTypeLoc TL, Sema::AbstractDiagSelID Sel) {
Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5684 CheckPolymorphic(MemberPointerTypeLoc)void Check(MemberPointerTypeLoc TL, Sema::AbstractDiagSelID Sel
) { Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5685 CheckPolymorphic(BlockPointerTypeLoc)void Check(BlockPointerTypeLoc TL, Sema::AbstractDiagSelID Sel
) { Visit(TL.getNextTypeLoc(), Sema::AbstractNone); }
5686 CheckPolymorphic(AtomicTypeLoc)void Check(AtomicTypeLoc TL, Sema::AbstractDiagSelID Sel) { Visit
(TL.getNextTypeLoc(), Sema::AbstractNone); }
5687
5688 /// Handle all the types we haven't given a more specific
5689 /// implementation for above.
5690 void Check(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
5691 // Every other kind of type that we haven't called out already
5692 // that has an inner type is either (1) sugar or (2) contains that
5693 // inner type in some way as a subobject.
5694 if (TypeLoc Next = TL.getNextTypeLoc())
5695 return Visit(Next, Sel);
5696
5697 // If there's no inner type and we're in a permissive context,
5698 // don't diagnose.
5699 if (Sel == Sema::AbstractNone) return;
5700
5701 // Check whether the type matches the abstract type.
5702 QualType T = TL.getType();
5703 if (T->isArrayType()) {
5704 Sel = Sema::AbstractArrayType;
5705 T = Info.S.Context.getBaseElementType(T);
5706 }
5707 CanQualType CT = T->getCanonicalTypeUnqualified().getUnqualifiedType();
5708 if (CT != Info.AbstractType) return;
5709
5710 // It matched; do some magic.
5711 if (Sel == Sema::AbstractArrayType) {
5712 Info.S.Diag(Ctx->getLocation(), diag::err_array_of_abstract_type)
5713 << T << TL.getSourceRange();
5714 } else {
5715 Info.S.Diag(Ctx->getLocation(), diag::err_abstract_type_in_decl)
5716 << Sel << T << TL.getSourceRange();
5717 }
5718 Info.DiagnoseAbstractType();
5719 }
5720};
5721
5722void AbstractUsageInfo::CheckType(const NamedDecl *D, TypeLoc TL,
5723 Sema::AbstractDiagSelID Sel) {
5724 CheckAbstractUsage(*this, D).Visit(TL, Sel);
5725}
5726
5727}
5728
5729/// Check for invalid uses of an abstract type in a method declaration.
5730static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
5731 CXXMethodDecl *MD) {
5732 // No need to do the check on definitions, which require that
5733 // the return/param types be complete.
5734 if (MD->doesThisDeclarationHaveABody())
5735 return;
5736
5737 // For safety's sake, just ignore it if we don't have type source
5738 // information. This should never happen for non-implicit methods,
5739 // but...
5740 if (TypeSourceInfo *TSI = MD->getTypeSourceInfo())
5741 Info.CheckType(MD, TSI->getTypeLoc(), Sema::AbstractNone);
5742}
5743
5744/// Check for invalid uses of an abstract type within a class definition.
5745static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
5746 CXXRecordDecl *RD) {
5747 for (auto *D : RD->decls()) {
5748 if (D->isImplicit()) continue;
5749
5750 // Methods and method templates.
5751 if (isa<CXXMethodDecl>(D)) {
5752 CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(D));
5753 } else if (isa<FunctionTemplateDecl>(D)) {
5754 FunctionDecl *FD = cast<FunctionTemplateDecl>(D)->getTemplatedDecl();
5755 CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(FD));
5756
5757 // Fields and static variables.
5758 } else if (isa<FieldDecl>(D)) {
5759 FieldDecl *FD = cast<FieldDecl>(D);
5760 if (TypeSourceInfo *TSI = FD->getTypeSourceInfo())
5761 Info.CheckType(FD, TSI->getTypeLoc(), Sema::AbstractFieldType);
5762 } else if (isa<VarDecl>(D)) {
5763 VarDecl *VD = cast<VarDecl>(D);
5764 if (TypeSourceInfo *TSI = VD->getTypeSourceInfo())
5765 Info.CheckType(VD, TSI->getTypeLoc(), Sema::AbstractVariableType);
5766
5767 // Nested classes and class templates.
5768 } else if (isa<CXXRecordDecl>(D)) {
5769 CheckAbstractClassUsage(Info, cast<CXXRecordDecl>(D));
5770 } else if (isa<ClassTemplateDecl>(D)) {
5771 CheckAbstractClassUsage(Info,
5772 cast<ClassTemplateDecl>(D)->getTemplatedDecl());
5773 }
5774 }
5775}
5776
5777static void ReferenceDllExportedMembers(Sema &S, CXXRecordDecl *Class) {
5778 Attr *ClassAttr = getDLLAttr(Class);
5779 if (!ClassAttr)
5780 return;
5781
5782 assert(ClassAttr->getKind() == attr::DLLExport)((ClassAttr->getKind() == attr::DLLExport) ? static_cast<
void> (0) : __assert_fail ("ClassAttr->getKind() == attr::DLLExport"
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 5782, __PRETTY_FUNCTION__))
;
5783
5784 TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
5785
5786 if (TSK == TSK_ExplicitInstantiationDeclaration)
5787 // Don't go any further if this is just an explicit instantiation
5788 // declaration.
5789 return;
5790
5791 if (S.Context.getTargetInfo().getTriple().isWindowsGNUEnvironment())
5792 S.MarkVTableUsed(Class->getLocation(), Class, true);
5793
5794 for (Decl *Member : Class->decls()) {
5795 // Defined static variables that are members of an exported base
5796 // class must be marked export too.
5797 auto *VD = dyn_cast<VarDecl>(Member);
5798 if (VD && Member->getAttr<DLLExportAttr>() &&
5799 VD->getStorageClass() == SC_Static &&
5800 TSK == TSK_ImplicitInstantiation)
5801 S.MarkVariableReferenced(VD->getLocation(), VD);
5802
5803 auto *MD = dyn_cast<CXXMethodDecl>(Member);
5804 if (!MD)
5805 continue;
5806
5807 if (Member->getAttr<DLLExportAttr>()) {
5808 if (MD->isUserProvided()) {
5809 // Instantiate non-default class member functions ...
5810
5811 // .. except for certain kinds of template specializations.
5812 if (TSK == TSK_ImplicitInstantiation && !ClassAttr->isInherited())
5813 continue;
5814
5815 S.MarkFunctionReferenced(Class->getLocation(), MD);
5816
5817 // The function will be passed to the consumer when its definition is
5818 // encountered.
5819 } else if (!MD->isTrivial() || MD->isExplicitlyDefaulted() ||
5820 MD->isCopyAssignmentOperator() ||
5821 MD->isMoveAssignmentOperator()) {
5822 // Synthesize and instantiate non-trivial implicit methods, explicitly
5823 // defaulted methods, and the copy and move assignment operators. The
5824 // latter are exported even if they are trivial, because the address of
5825 // an operator can be taken and should compare equal across libraries.
5826 DiagnosticErrorTrap Trap(S.Diags);
5827 S.MarkFunctionReferenced(Class->getLocation(), MD);
5828 if (Trap.hasErrorOccurred()) {
5829 S.Diag(ClassAttr->getLocation(), diag::note_due_to_dllexported_class)
5830 << Class << !S.getLangOpts().CPlusPlus11;
5831 break;
5832 }
5833
5834 // There is no later point when we will see the definition of this
5835 // function, so pass it to the consumer now.
5836 S.Consumer.HandleTopLevelDecl(DeclGroupRef(MD));
5837 }
5838 }
5839 }
5840}
5841
5842static void checkForMultipleExportedDefaultConstructors(Sema &S,
5843 CXXRecordDecl *Class) {
5844 // Only the MS ABI has default constructor closures, so we don't need to do
5845 // this semantic checking anywhere else.
5846 if (!S.Context.getTargetInfo().getCXXABI().isMicrosoft())
5847 return;
5848
5849 CXXConstructorDecl *LastExportedDefaultCtor = nullptr;
5850 for (Decl *Member : Class->decls()) {
5851 // Look for exported default constructors.
5852 auto *CD = dyn_cast<CXXConstructorDecl>(Member);
5853 if (!CD || !CD->isDefaultConstructor())
5854 continue;
5855 auto *Attr = CD->getAttr<DLLExportAttr>();
5856 if (!Attr)
5857 continue;
5858
5859 // If the class is non-dependent, mark the default arguments as ODR-used so
5860 // that we can properly codegen the constructor closure.
5861 if (!Class->isDependentContext()) {
5862 for (ParmVarDecl *PD : CD->parameters()) {
5863 (void)S.CheckCXXDefaultArgExpr(Attr->getLocation(), CD, PD);
5864 S.DiscardCleanupsInEvaluationContext();
5865 }
5866 }
5867
5868 if (LastExportedDefaultCtor) {
5869 S.Diag(LastExportedDefaultCtor->getLocation(),
5870 diag::err_attribute_dll_ambiguous_default_ctor)
5871 << Class;
5872 S.Diag(CD->getLocation(), diag::note_entity_declared_at)
5873 << CD->getDeclName();
5874 return;
5875 }
5876 LastExportedDefaultCtor = CD;
5877 }
5878}
5879
5880void Sema::checkClassLevelCodeSegAttribute(CXXRecordDecl *Class) {
5881 // Mark any compiler-generated routines with the implicit code_seg attribute.
5882 for (auto *Method : Class->methods()) {
5883 if (Method->isUserProvided())
5884 continue;
5885 if (Attr *A = getImplicitCodeSegOrSectionAttrForFunction(Method, /*IsDefinition=*/true))
5886 Method->addAttr(A);
5887 }
5888}
5889
5890/// Check class-level dllimport/dllexport attribute.
5891void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
5892 Attr *ClassAttr = getDLLAttr(Class);
5893
5894 // MSVC inherits DLL attributes to partial class template specializations.
5895 if (Context.getTargetInfo().getCXXABI().isMicrosoft() && !ClassAttr) {
5896 if (auto *Spec = dyn_cast<ClassTemplatePartialSpecializationDecl>(Class)) {
5897 if (Attr *TemplateAttr =
5898 getDLLAttr(Spec->getSpecializedTemplate()->getTemplatedDecl())) {
5899 auto *A = cast<InheritableAttr>(TemplateAttr->clone(getASTContext()));
5900 A->setInherited(true);
5901 ClassAttr = A;
5902 }
5903 }
5904 }
5905
5906 if (!ClassAttr)
5907 return;
5908
5909 if (!Class->isExternallyVisible()) {
5910 Diag(Class->getLocation(), diag::err_attribute_dll_not_extern)
5911 << Class << ClassAttr;
5912 return;
5913 }
5914
5915 if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
5916 !ClassAttr->isInherited()) {
5917 // Diagnose dll attributes on members of class with dll attribute.
5918 for (Decl *Member : Class->decls()) {
5919 if (!isa<VarDecl>(Member) && !isa<CXXMethodDecl>(Member))
5920 continue;
5921 InheritableAttr *MemberAttr = getDLLAttr(Member);
5922 if (!MemberAttr || MemberAttr->isInherited() || Member->isInvalidDecl())
5923 continue;
5924
5925 Diag(MemberAttr->getLocation(),
5926 diag::err_attribute_dll_member_of_dll_class)
5927 << MemberAttr << ClassAttr;
5928 Diag(ClassAttr->getLocation(), diag::note_previous_attribute);
5929 Member->setInvalidDecl();
5930 }
5931 }
5932
5933 if (Class->getDescribedClassTemplate())
5934 // Don't inherit dll attribute until the template is instantiated.
5935 return;
5936
5937 // The class is either imported or exported.
5938 const bool ClassExported = ClassAttr->getKind() == attr::DLLExport;
5939
5940 // Check if this was a dllimport attribute propagated from a derived class to
5941 // a base class template specialization. We don't apply these attributes to
5942 // static data members.
5943 const bool PropagatedImport =
5944 !ClassExported &&
5945 cast<DLLImportAttr>(ClassAttr)->wasPropagatedToBaseTemplate();
5946
5947 TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
5948
5949 // Ignore explicit dllexport on explicit class template instantiation
5950 // declarations, except in MinGW mode.
5951 if (ClassExported && !ClassAttr->isInherited() &&
5952 TSK == TSK_ExplicitInstantiationDeclaration &&
5953 !Context.getTargetInfo().getTriple().isWindowsGNUEnvironment()) {
5954 Class->dropAttr<DLLExportAttr>();
5955 return;
5956 }
5957
5958 // Force declaration of implicit members so they can inherit the attribute.
5959 ForceDeclarationOfImplicitMembers(Class);
5960
5961 // FIXME: MSVC's docs say all bases must be exportable, but this doesn't
5962 // seem to be true in practice?
5963
5964 for (Decl *Member : Class->decls()) {
5965 VarDecl *VD = dyn_cast<VarDecl>(Member);
5966 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member);
5967
5968 // Only methods and static fields inherit the attributes.
5969 if (!VD && !MD)
5970 continue;
5971
5972 if (MD) {
5973 // Don't process deleted methods.
5974 if (MD->isDeleted())
5975 continue;
5976
5977 if (MD->isInlined()) {
5978 // MinGW does not import or export inline methods. But do it for
5979 // template instantiations.
5980 if (!Context.getTargetInfo().getCXXABI().isMicrosoft() &&
5981 !Context.getTargetInfo().getTriple().isWindowsItaniumEnvironment() &&
5982 TSK != TSK_ExplicitInstantiationDeclaration &&
5983 TSK != TSK_ExplicitInstantiationDefinition)
5984 continue;
5985
5986 // MSVC versions before 2015 don't export the move assignment operators
5987 // and move constructor, so don't attempt to import/export them if
5988 // we have a definition.
5989 auto *Ctor = dyn_cast<CXXConstructorDecl>(MD);
5990 if ((MD->isMoveAssignmentOperator() ||
5991 (Ctor && Ctor->isMoveConstructor())) &&
5992 !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
5993 continue;
5994
5995 // MSVC2015 doesn't export trivial defaulted x-tor but copy assign
5996 // operator is exported anyway.
5997 if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
5998 (Ctor || isa<CXXDestructorDecl>(MD)) && MD->isTrivial())
5999 continue;
6000 }
6001 }
6002
6003 // Don't apply dllimport attributes to static data members of class template
6004 // instantiations when the attribute is propagated from a derived class.
6005 if (VD && PropagatedImport)
6006 continue;
6007
6008 if (!cast<NamedDecl>(Member)->isExternallyVisible())
6009 continue;
6010
6011 if (!getDLLAttr(Member)) {
6012 InheritableAttr *NewAttr = nullptr;
6013
6014 // Do not export/import inline function when -fno-dllexport-inlines is
6015 // passed. But add attribute for later local static var check.
6016 if (!getLangOpts().DllExportInlines && MD && MD->isInlined() &&
6017 TSK != TSK_ExplicitInstantiationDeclaration &&
6018 TSK != TSK_ExplicitInstantiationDefinition) {
6019 if (ClassExported) {
6020 NewAttr = ::new (getASTContext())
6021 DLLExportStaticLocalAttr(getASTContext(), *ClassAttr);
6022 } else {
6023 NewAttr = ::new (getASTContext())
6024 DLLImportStaticLocalAttr(getASTContext(), *ClassAttr);
6025 }
6026 } else {
6027 NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
6028 }
6029
6030 NewAttr->setInherited(true);
6031 Member->addAttr(NewAttr);
6032
6033 if (MD) {
6034 // Propagate DLLAttr to friend re-declarations of MD that have already
6035 // been constructed.
6036 for (FunctionDecl *FD = MD->getMostRecentDecl(); FD;
6037 FD = FD->getPreviousDecl()) {
6038 if (FD->getFriendObjectKind() == Decl::FOK_None)
6039 continue;
6040 assert(!getDLLAttr(FD) &&((!getDLLAttr(FD) && "friend re-decl should not already have a DLLAttr"
) ? static_cast<void> (0) : __assert_fail ("!getDLLAttr(FD) && \"friend re-decl should not already have a DLLAttr\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 6041, __PRETTY_FUNCTION__))
6041 "friend re-decl should not already have a DLLAttr")((!getDLLAttr(FD) && "friend re-decl should not already have a DLLAttr"
) ? static_cast<void> (0) : __assert_fail ("!getDLLAttr(FD) && \"friend re-decl should not already have a DLLAttr\""
, "/build/llvm-toolchain-snapshot-11~++20200309111110+2c36c23f347/clang/lib/Sema/SemaDeclCXX.cpp"
, 6041, __PRETTY_FUNCTION__))
;
6042 NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
6043 NewAttr->setInherited(true);
6044 FD->addAttr(NewAttr);
6045 }
6046 }
6047 }
6048 }
6049
6050 if (ClassExported)
6051 DelayedDllExportClasses.push_back(Class);
6052}
6053
6054/// Perform propagation of DLL attributes from a derived class to a
6055/// templated base class for MS compatibility.
6056void Sema::propagateDLLAttrToBaseClassTemplate(
6057 CXXRecordDecl *Class, Attr *ClassAttr,
6058 ClassTemplateSpecializationDecl *BaseTemplateSpec, SourceLocation BaseLoc) {
6059 if (getDLLAttr(
6060 BaseTemplateSpec->getSpecializedTemplate()->getTemplatedDecl())) {
6061 // If the base class template has a DLL attribute, don't try to change it.
6062 return;
6063 }
6064
6065 auto TSK = BaseTemplateSpec->getSpecializationKind();
6066 if (!getDLLAttr(BaseTemplateSpec) &&
6067 (TSK == TSK_Undeclared || TSK == TSK_ExplicitInstantiationDeclaration ||
6068 TSK == TSK_ImplicitInstantiation)) {
6069 // The template hasn't been instantiated yet (or it has, but only as an
6070 // explicit instantiation declaration or implicit instantiation, which means
6071 // we haven't codegenned any members yet), so propagate the attribute.
6072 auto *NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
6073 NewAttr->setInherited(true);
6074 BaseTemplateSpec->addAttr(NewAttr);
6075
6076 // If this was an import, mark that we propagated it from a derived class to
6077 // a base class template specialization.
6078 if (auto *ImportAttr = dyn_cast<DLLImportAttr>(NewAttr))
6079 ImportAttr->setPropagatedToBaseTemplate();
6080
6081 // If the template is already instantiated, checkDLLAttributeRedeclaration()
6082 // needs to be run again to work see the new attribute. Otherwise this will
6083 // get run whenever the template is instantiated.
6084 if (TSK != TSK_Undeclared)
6085 checkClassLevelDLLAttribute(BaseTemplateSpec);
6086
6087 return;
6088 }
6089
6090 if (getDLLAttr(BaseTemplateSpec)) {
6091 // The template has already been specialized or instantiated with an
6092 // attribute, explicitly or through propagation. We should not try to change
6093 // it.
6094 return;
6095 }
6096
6097 // The template was previously instantiated or explicitly specialized without
6098 // a dll attribute, It's too late for us to add an attribute, so warn that
6099 // this is unsupported.
6100 Diag(BaseLoc, diag::warn_attribute_dll_instantiated_base_class)
6101 << BaseTemplateSpec->isExplicitSpecialization();
6102 Diag(ClassAttr->getLocation(), diag::note_attribute);
6103 if (BaseTemplateSpec->isExplicitSpecialization()) {
6104 Diag(BaseTemplateSpec->getLocation(),
6105 diag::note_template_class_explicit_specialization_was_here)
6106 << BaseTemplateS