Bug Summary

File:tools/clang/lib/Sema/SemaAccess.cpp
Warning:line 1554, column 16
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 SemaAccess.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 -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mthread-model posix -mframe-pointer=none -relaxed-aliasing -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -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-10~svn373517/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-10~svn373517/tools/clang/include -I /build/llvm-toolchain-snapshot-10~svn373517/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-10~svn373517/build-llvm/include -I /build/llvm-toolchain-snapshot-10~svn373517/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-10/lib/clang/10.0.0/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-10~svn373517/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-10~svn373517=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -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-2019-10-02-234743-9763-1 -x c++ /build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp
1//===---- SemaAccess.cpp - C++ Access Control -------------------*- C++ -*-===//
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 provides Sema routines for C++ access control semantics.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/Basic/Specifiers.h"
14#include "clang/Sema/SemaInternal.h"
15#include "clang/AST/ASTContext.h"
16#include "clang/AST/CXXInheritance.h"
17#include "clang/AST/DeclCXX.h"
18#include "clang/AST/DeclFriend.h"
19#include "clang/AST/DeclObjC.h"
20#include "clang/AST/DependentDiagnostic.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/Sema/DelayedDiagnostic.h"
23#include "clang/Sema/Initialization.h"
24#include "clang/Sema/Lookup.h"
25
26using namespace clang;
27using namespace sema;
28
29/// A copy of Sema's enum without AR_delayed.
30enum AccessResult {
31 AR_accessible,
32 AR_inaccessible,
33 AR_dependent
34};
35
36/// SetMemberAccessSpecifier - Set the access specifier of a member.
37/// Returns true on error (when the previous member decl access specifier
38/// is different from the new member decl access specifier).
39bool Sema::SetMemberAccessSpecifier(NamedDecl *MemberDecl,
40 NamedDecl *PrevMemberDecl,
41 AccessSpecifier LexicalAS) {
42 if (!PrevMemberDecl) {
43 // Use the lexical access specifier.
44 MemberDecl->setAccess(LexicalAS);
45 return false;
46 }
47
48 // C++ [class.access.spec]p3: When a member is redeclared its access
49 // specifier must be same as its initial declaration.
50 if (LexicalAS != AS_none && LexicalAS != PrevMemberDecl->getAccess()) {
51 Diag(MemberDecl->getLocation(),
52 diag::err_class_redeclared_with_different_access)
53 << MemberDecl << LexicalAS;
54 Diag(PrevMemberDecl->getLocation(), diag::note_previous_access_declaration)
55 << PrevMemberDecl << PrevMemberDecl->getAccess();
56
57 MemberDecl->setAccess(LexicalAS);
58 return true;
59 }
60
61 MemberDecl->setAccess(PrevMemberDecl->getAccess());
62 return false;
63}
64
65static CXXRecordDecl *FindDeclaringClass(NamedDecl *D) {
66 DeclContext *DC = D->getDeclContext();
67
68 // This can only happen at top: enum decls only "publish" their
69 // immediate members.
70 if (isa<EnumDecl>(DC))
71 DC = cast<EnumDecl>(DC)->getDeclContext();
72
73 CXXRecordDecl *DeclaringClass = cast<CXXRecordDecl>(DC);
74 while (DeclaringClass->isAnonymousStructOrUnion())
75 DeclaringClass = cast<CXXRecordDecl>(DeclaringClass->getDeclContext());
76 return DeclaringClass;
77}
78
79namespace {
80struct EffectiveContext {
81 EffectiveContext() : Inner(nullptr), Dependent(false) {}
82
83 explicit EffectiveContext(DeclContext *DC)
84 : Inner(DC),
85 Dependent(DC->isDependentContext()) {
86
87 // C++11 [class.access.nest]p1:
88 // A nested class is a member and as such has the same access
89 // rights as any other member.
90 // C++11 [class.access]p2:
91 // A member of a class can also access all the names to which
92 // the class has access. A local class of a member function
93 // may access the same names that the member function itself
94 // may access.
95 // This almost implies that the privileges of nesting are transitive.
96 // Technically it says nothing about the local classes of non-member
97 // functions (which can gain privileges through friendship), but we
98 // take that as an oversight.
99 while (true) {
100 // We want to add canonical declarations to the EC lists for
101 // simplicity of checking, but we need to walk up through the
102 // actual current DC chain. Otherwise, something like a local
103 // extern or friend which happens to be the canonical
104 // declaration will really mess us up.
105
106 if (isa<CXXRecordDecl>(DC)) {
107 CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
108 Records.push_back(Record->getCanonicalDecl());
109 DC = Record->getDeclContext();
110 } else if (isa<FunctionDecl>(DC)) {
111 FunctionDecl *Function = cast<FunctionDecl>(DC);
112 Functions.push_back(Function->getCanonicalDecl());
113 if (Function->getFriendObjectKind())
114 DC = Function->getLexicalDeclContext();
115 else
116 DC = Function->getDeclContext();
117 } else if (DC->isFileContext()) {
118 break;
119 } else {
120 DC = DC->getParent();
121 }
122 }
123 }
124
125 bool isDependent() const { return Dependent; }
126
127 bool includesClass(const CXXRecordDecl *R) const {
128 R = R->getCanonicalDecl();
129 return llvm::find(Records, R) != Records.end();
130 }
131
132 /// Retrieves the innermost "useful" context. Can be null if we're
133 /// doing access-control without privileges.
134 DeclContext *getInnerContext() const {
135 return Inner;
136 }
137
138 typedef SmallVectorImpl<CXXRecordDecl*>::const_iterator record_iterator;
139
140 DeclContext *Inner;
141 SmallVector<FunctionDecl*, 4> Functions;
142 SmallVector<CXXRecordDecl*, 4> Records;
143 bool Dependent;
144};
145
146/// Like sema::AccessedEntity, but kindly lets us scribble all over
147/// it.
148struct AccessTarget : public AccessedEntity {
149 AccessTarget(const AccessedEntity &Entity)
150 : AccessedEntity(Entity) {
151 initialize();
152 }
153
154 AccessTarget(ASTContext &Context,
155 MemberNonce _,
156 CXXRecordDecl *NamingClass,
157 DeclAccessPair FoundDecl,
158 QualType BaseObjectType)
159 : AccessedEntity(Context.getDiagAllocator(), Member, NamingClass,
160 FoundDecl, BaseObjectType) {
161 initialize();
162 }
163
164 AccessTarget(ASTContext &Context,
165 BaseNonce _,
166 CXXRecordDecl *BaseClass,
167 CXXRecordDecl *DerivedClass,
168 AccessSpecifier Access)
169 : AccessedEntity(Context.getDiagAllocator(), Base, BaseClass, DerivedClass,
170 Access) {
171 initialize();
172 }
173
174 bool isInstanceMember() const {
175 return (isMemberAccess() && getTargetDecl()->isCXXInstanceMember());
176 }
177
178 bool hasInstanceContext() const {
179 return HasInstanceContext;
180 }
181
182 class SavedInstanceContext {
183 public:
184 SavedInstanceContext(SavedInstanceContext &&S)
185 : Target(S.Target), Has(S.Has) {
186 S.Target = nullptr;
187 }
188 ~SavedInstanceContext() {
189 if (Target)
190 Target->HasInstanceContext = Has;
191 }
192
193 private:
194 friend struct AccessTarget;
195 explicit SavedInstanceContext(AccessTarget &Target)
196 : Target(&Target), Has(Target.HasInstanceContext) {}
197 AccessTarget *Target;
198 bool Has;
199 };
200
201 SavedInstanceContext saveInstanceContext() {
202 return SavedInstanceContext(*this);
203 }
204
205 void suppressInstanceContext() {
206 HasInstanceContext = false;
207 }
208
209 const CXXRecordDecl *resolveInstanceContext(Sema &S) const {
210 assert(HasInstanceContext)((HasInstanceContext) ? static_cast<void> (0) : __assert_fail
("HasInstanceContext", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 210, __PRETTY_FUNCTION__))
;
211 if (CalculatedInstanceContext)
212 return InstanceContext;
213
214 CalculatedInstanceContext = true;
215 DeclContext *IC = S.computeDeclContext(getBaseObjectType());
216 InstanceContext = (IC ? cast<CXXRecordDecl>(IC)->getCanonicalDecl()
217 : nullptr);
218 return InstanceContext;
219 }
220
221 const CXXRecordDecl *getDeclaringClass() const {
222 return DeclaringClass;
223 }
224
225 /// The "effective" naming class is the canonical non-anonymous
226 /// class containing the actual naming class.
227 const CXXRecordDecl *getEffectiveNamingClass() const {
228 const CXXRecordDecl *namingClass = getNamingClass();
229 while (namingClass->isAnonymousStructOrUnion())
230 namingClass = cast<CXXRecordDecl>(namingClass->getParent());
231 return namingClass->getCanonicalDecl();
232 }
233
234private:
235 void initialize() {
236 HasInstanceContext = (isMemberAccess() &&
237 !getBaseObjectType().isNull() &&
238 getTargetDecl()->isCXXInstanceMember());
239 CalculatedInstanceContext = false;
240 InstanceContext = nullptr;
241
242 if (isMemberAccess())
243 DeclaringClass = FindDeclaringClass(getTargetDecl());
244 else
245 DeclaringClass = getBaseClass();
246 DeclaringClass = DeclaringClass->getCanonicalDecl();
247 }
248
249 bool HasInstanceContext : 1;
250 mutable bool CalculatedInstanceContext : 1;
251 mutable const CXXRecordDecl *InstanceContext;
252 const CXXRecordDecl *DeclaringClass;
253};
254
255}
256
257/// Checks whether one class might instantiate to the other.
258static bool MightInstantiateTo(const CXXRecordDecl *From,
259 const CXXRecordDecl *To) {
260 // Declaration names are always preserved by instantiation.
261 if (From->getDeclName() != To->getDeclName())
262 return false;
263
264 const DeclContext *FromDC = From->getDeclContext()->getPrimaryContext();
265 const DeclContext *ToDC = To->getDeclContext()->getPrimaryContext();
266 if (FromDC == ToDC) return true;
267 if (FromDC->isFileContext() || ToDC->isFileContext()) return false;
268
269 // Be conservative.
270 return true;
271}
272
273/// Checks whether one class is derived from another, inclusively.
274/// Properly indicates when it couldn't be determined due to
275/// dependence.
276///
277/// This should probably be donated to AST or at least Sema.
278static AccessResult IsDerivedFromInclusive(const CXXRecordDecl *Derived,
279 const CXXRecordDecl *Target) {
280 assert(Derived->getCanonicalDecl() == Derived)((Derived->getCanonicalDecl() == Derived) ? static_cast<
void> (0) : __assert_fail ("Derived->getCanonicalDecl() == Derived"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 280, __PRETTY_FUNCTION__))
;
281 assert(Target->getCanonicalDecl() == Target)((Target->getCanonicalDecl() == Target) ? static_cast<void
> (0) : __assert_fail ("Target->getCanonicalDecl() == Target"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 281, __PRETTY_FUNCTION__))
;
282
283 if (Derived == Target) return AR_accessible;
284
285 bool CheckDependent = Derived->isDependentContext();
286 if (CheckDependent && MightInstantiateTo(Derived, Target))
287 return AR_dependent;
288
289 AccessResult OnFailure = AR_inaccessible;
290 SmallVector<const CXXRecordDecl*, 8> Queue; // actually a stack
291
292 while (true) {
293 if (Derived->isDependentContext() && !Derived->hasDefinition() &&
294 !Derived->isLambda())
295 return AR_dependent;
296
297 for (const auto &I : Derived->bases()) {
298 const CXXRecordDecl *RD;
299
300 QualType T = I.getType();
301 if (const RecordType *RT = T->getAs<RecordType>()) {
302 RD = cast<CXXRecordDecl>(RT->getDecl());
303 } else if (const InjectedClassNameType *IT
304 = T->getAs<InjectedClassNameType>()) {
305 RD = IT->getDecl();
306 } else {
307 assert(T->isDependentType() && "non-dependent base wasn't a record?")((T->isDependentType() && "non-dependent base wasn't a record?"
) ? static_cast<void> (0) : __assert_fail ("T->isDependentType() && \"non-dependent base wasn't a record?\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 307, __PRETTY_FUNCTION__))
;
308 OnFailure = AR_dependent;
309 continue;
310 }
311
312 RD = RD->getCanonicalDecl();
313 if (RD == Target) return AR_accessible;
314 if (CheckDependent && MightInstantiateTo(RD, Target))
315 OnFailure = AR_dependent;
316
317 Queue.push_back(RD);
318 }
319
320 if (Queue.empty()) break;
321
322 Derived = Queue.pop_back_val();
323 }
324
325 return OnFailure;
326}
327
328
329static bool MightInstantiateTo(Sema &S, DeclContext *Context,
330 DeclContext *Friend) {
331 if (Friend == Context)
332 return true;
333
334 assert(!Friend->isDependentContext() &&((!Friend->isDependentContext() && "can't handle friends with dependent contexts here"
) ? static_cast<void> (0) : __assert_fail ("!Friend->isDependentContext() && \"can't handle friends with dependent contexts here\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 335, __PRETTY_FUNCTION__))
335 "can't handle friends with dependent contexts here")((!Friend->isDependentContext() && "can't handle friends with dependent contexts here"
) ? static_cast<void> (0) : __assert_fail ("!Friend->isDependentContext() && \"can't handle friends with dependent contexts here\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 335, __PRETTY_FUNCTION__))
;
336
337 if (!Context->isDependentContext())
338 return false;
339
340 if (Friend->isFileContext())
341 return false;
342
343 // TODO: this is very conservative
344 return true;
345}
346
347// Asks whether the type in 'context' can ever instantiate to the type
348// in 'friend'.
349static bool MightInstantiateTo(Sema &S, CanQualType Context, CanQualType Friend) {
350 if (Friend == Context)
351 return true;
352
353 if (!Friend->isDependentType() && !Context->isDependentType())
354 return false;
355
356 // TODO: this is very conservative.
357 return true;
358}
359
360static bool MightInstantiateTo(Sema &S,
361 FunctionDecl *Context,
362 FunctionDecl *Friend) {
363 if (Context->getDeclName() != Friend->getDeclName())
364 return false;
365
366 if (!MightInstantiateTo(S,
367 Context->getDeclContext(),
368 Friend->getDeclContext()))
369 return false;
370
371 CanQual<FunctionProtoType> FriendTy
372 = S.Context.getCanonicalType(Friend->getType())
373 ->getAs<FunctionProtoType>();
374 CanQual<FunctionProtoType> ContextTy
375 = S.Context.getCanonicalType(Context->getType())
376 ->getAs<FunctionProtoType>();
377
378 // There isn't any way that I know of to add qualifiers
379 // during instantiation.
380 if (FriendTy.getQualifiers() != ContextTy.getQualifiers())
381 return false;
382
383 if (FriendTy->getNumParams() != ContextTy->getNumParams())
384 return false;
385
386 if (!MightInstantiateTo(S, ContextTy->getReturnType(),
387 FriendTy->getReturnType()))
388 return false;
389
390 for (unsigned I = 0, E = FriendTy->getNumParams(); I != E; ++I)
391 if (!MightInstantiateTo(S, ContextTy->getParamType(I),
392 FriendTy->getParamType(I)))
393 return false;
394
395 return true;
396}
397
398static bool MightInstantiateTo(Sema &S,
399 FunctionTemplateDecl *Context,
400 FunctionTemplateDecl *Friend) {
401 return MightInstantiateTo(S,
402 Context->getTemplatedDecl(),
403 Friend->getTemplatedDecl());
404}
405
406static AccessResult MatchesFriend(Sema &S,
407 const EffectiveContext &EC,
408 const CXXRecordDecl *Friend) {
409 if (EC.includesClass(Friend))
410 return AR_accessible;
411
412 if (EC.isDependent()) {
413 for (const CXXRecordDecl *Context : EC.Records) {
414 if (MightInstantiateTo(Context, Friend))
415 return AR_dependent;
416 }
417 }
418
419 return AR_inaccessible;
420}
421
422static AccessResult MatchesFriend(Sema &S,
423 const EffectiveContext &EC,
424 CanQualType Friend) {
425 if (const RecordType *RT = Friend->getAs<RecordType>())
426 return MatchesFriend(S, EC, cast<CXXRecordDecl>(RT->getDecl()));
427
428 // TODO: we can do better than this
429 if (Friend->isDependentType())
430 return AR_dependent;
431
432 return AR_inaccessible;
433}
434
435/// Determines whether the given friend class template matches
436/// anything in the effective context.
437static AccessResult MatchesFriend(Sema &S,
438 const EffectiveContext &EC,
439 ClassTemplateDecl *Friend) {
440 AccessResult OnFailure = AR_inaccessible;
441
442 // Check whether the friend is the template of a class in the
443 // context chain.
444 for (SmallVectorImpl<CXXRecordDecl*>::const_iterator
445 I = EC.Records.begin(), E = EC.Records.end(); I != E; ++I) {
446 CXXRecordDecl *Record = *I;
447
448 // Figure out whether the current class has a template:
449 ClassTemplateDecl *CTD;
450
451 // A specialization of the template...
452 if (isa<ClassTemplateSpecializationDecl>(Record)) {
453 CTD = cast<ClassTemplateSpecializationDecl>(Record)
454 ->getSpecializedTemplate();
455
456 // ... or the template pattern itself.
457 } else {
458 CTD = Record->getDescribedClassTemplate();
459 if (!CTD) continue;
460 }
461
462 // It's a match.
463 if (Friend == CTD->getCanonicalDecl())
464 return AR_accessible;
465
466 // If the context isn't dependent, it can't be a dependent match.
467 if (!EC.isDependent())
468 continue;
469
470 // If the template names don't match, it can't be a dependent
471 // match.
472 if (CTD->getDeclName() != Friend->getDeclName())
473 continue;
474
475 // If the class's context can't instantiate to the friend's
476 // context, it can't be a dependent match.
477 if (!MightInstantiateTo(S, CTD->getDeclContext(),
478 Friend->getDeclContext()))
479 continue;
480
481 // Otherwise, it's a dependent match.
482 OnFailure = AR_dependent;
483 }
484
485 return OnFailure;
486}
487
488/// Determines whether the given friend function matches anything in
489/// the effective context.
490static AccessResult MatchesFriend(Sema &S,
491 const EffectiveContext &EC,
492 FunctionDecl *Friend) {
493 AccessResult OnFailure = AR_inaccessible;
494
495 for (SmallVectorImpl<FunctionDecl*>::const_iterator
496 I = EC.Functions.begin(), E = EC.Functions.end(); I != E; ++I) {
497 if (Friend == *I)
498 return AR_accessible;
499
500 if (EC.isDependent() && MightInstantiateTo(S, *I, Friend))
501 OnFailure = AR_dependent;
502 }
503
504 return OnFailure;
505}
506
507/// Determines whether the given friend function template matches
508/// anything in the effective context.
509static AccessResult MatchesFriend(Sema &S,
510 const EffectiveContext &EC,
511 FunctionTemplateDecl *Friend) {
512 if (EC.Functions.empty()) return AR_inaccessible;
513
514 AccessResult OnFailure = AR_inaccessible;
515
516 for (SmallVectorImpl<FunctionDecl*>::const_iterator
517 I = EC.Functions.begin(), E = EC.Functions.end(); I != E; ++I) {
518
519 FunctionTemplateDecl *FTD = (*I)->getPrimaryTemplate();
520 if (!FTD)
521 FTD = (*I)->getDescribedFunctionTemplate();
522 if (!FTD)
523 continue;
524
525 FTD = FTD->getCanonicalDecl();
526
527 if (Friend == FTD)
528 return AR_accessible;
529
530 if (EC.isDependent() && MightInstantiateTo(S, FTD, Friend))
531 OnFailure = AR_dependent;
532 }
533
534 return OnFailure;
535}
536
537/// Determines whether the given friend declaration matches anything
538/// in the effective context.
539static AccessResult MatchesFriend(Sema &S,
540 const EffectiveContext &EC,
541 FriendDecl *FriendD) {
542 // Whitelist accesses if there's an invalid or unsupported friend
543 // declaration.
544 if (FriendD->isInvalidDecl() || FriendD->isUnsupportedFriend())
545 return AR_accessible;
546
547 if (TypeSourceInfo *T = FriendD->getFriendType())
548 return MatchesFriend(S, EC, T->getType()->getCanonicalTypeUnqualified());
549
550 NamedDecl *Friend
551 = cast<NamedDecl>(FriendD->getFriendDecl()->getCanonicalDecl());
552
553 // FIXME: declarations with dependent or templated scope.
554
555 if (isa<ClassTemplateDecl>(Friend))
556 return MatchesFriend(S, EC, cast<ClassTemplateDecl>(Friend));
557
558 if (isa<FunctionTemplateDecl>(Friend))
559 return MatchesFriend(S, EC, cast<FunctionTemplateDecl>(Friend));
560
561 if (isa<CXXRecordDecl>(Friend))
562 return MatchesFriend(S, EC, cast<CXXRecordDecl>(Friend));
563
564 assert(isa<FunctionDecl>(Friend) && "unknown friend decl kind")((isa<FunctionDecl>(Friend) && "unknown friend decl kind"
) ? static_cast<void> (0) : __assert_fail ("isa<FunctionDecl>(Friend) && \"unknown friend decl kind\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 564, __PRETTY_FUNCTION__))
;
565 return MatchesFriend(S, EC, cast<FunctionDecl>(Friend));
566}
567
568static AccessResult GetFriendKind(Sema &S,
569 const EffectiveContext &EC,
570 const CXXRecordDecl *Class) {
571 AccessResult OnFailure = AR_inaccessible;
572
573 // Okay, check friends.
574 for (auto *Friend : Class->friends()) {
575 switch (MatchesFriend(S, EC, Friend)) {
576 case AR_accessible:
577 return AR_accessible;
578
579 case AR_inaccessible:
580 continue;
581
582 case AR_dependent:
583 OnFailure = AR_dependent;
584 break;
585 }
586 }
587
588 // That's it, give up.
589 return OnFailure;
590}
591
592namespace {
593
594/// A helper class for checking for a friend which will grant access
595/// to a protected instance member.
596struct ProtectedFriendContext {
597 Sema &S;
598 const EffectiveContext &EC;
599 const CXXRecordDecl *NamingClass;
600 bool CheckDependent;
601 bool EverDependent;
602
603 /// The path down to the current base class.
604 SmallVector<const CXXRecordDecl*, 20> CurPath;
605
606 ProtectedFriendContext(Sema &S, const EffectiveContext &EC,
607 const CXXRecordDecl *InstanceContext,
608 const CXXRecordDecl *NamingClass)
609 : S(S), EC(EC), NamingClass(NamingClass),
610 CheckDependent(InstanceContext->isDependentContext() ||
611 NamingClass->isDependentContext()),
612 EverDependent(false) {}
613
614 /// Check classes in the current path for friendship, starting at
615 /// the given index.
616 bool checkFriendshipAlongPath(unsigned I) {
617 assert(I < CurPath.size())((I < CurPath.size()) ? static_cast<void> (0) : __assert_fail
("I < CurPath.size()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 617, __PRETTY_FUNCTION__))
;
618 for (unsigned E = CurPath.size(); I != E; ++I) {
619 switch (GetFriendKind(S, EC, CurPath[I])) {
620 case AR_accessible: return true;
621 case AR_inaccessible: continue;
622 case AR_dependent: EverDependent = true; continue;
623 }
624 }
625 return false;
626 }
627
628 /// Perform a search starting at the given class.
629 ///
630 /// PrivateDepth is the index of the last (least derived) class
631 /// along the current path such that a notional public member of
632 /// the final class in the path would have access in that class.
633 bool findFriendship(const CXXRecordDecl *Cur, unsigned PrivateDepth) {
634 // If we ever reach the naming class, check the current path for
635 // friendship. We can also stop recursing because we obviously
636 // won't find the naming class there again.
637 if (Cur == NamingClass)
638 return checkFriendshipAlongPath(PrivateDepth);
639
640 if (CheckDependent && MightInstantiateTo(Cur, NamingClass))
641 EverDependent = true;
642
643 // Recurse into the base classes.
644 for (const auto &I : Cur->bases()) {
645 // If this is private inheritance, then a public member of the
646 // base will not have any access in classes derived from Cur.
647 unsigned BasePrivateDepth = PrivateDepth;
648 if (I.getAccessSpecifier() == AS_private)
649 BasePrivateDepth = CurPath.size() - 1;
650
651 const CXXRecordDecl *RD;
652
653 QualType T = I.getType();
654 if (const RecordType *RT = T->getAs<RecordType>()) {
655 RD = cast<CXXRecordDecl>(RT->getDecl());
656 } else if (const InjectedClassNameType *IT
657 = T->getAs<InjectedClassNameType>()) {
658 RD = IT->getDecl();
659 } else {
660 assert(T->isDependentType() && "non-dependent base wasn't a record?")((T->isDependentType() && "non-dependent base wasn't a record?"
) ? static_cast<void> (0) : __assert_fail ("T->isDependentType() && \"non-dependent base wasn't a record?\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 660, __PRETTY_FUNCTION__))
;
661 EverDependent = true;
662 continue;
663 }
664
665 // Recurse. We don't need to clean up if this returns true.
666 CurPath.push_back(RD);
667 if (findFriendship(RD->getCanonicalDecl(), BasePrivateDepth))
668 return true;
669 CurPath.pop_back();
670 }
671
672 return false;
673 }
674
675 bool findFriendship(const CXXRecordDecl *Cur) {
676 assert(CurPath.empty())((CurPath.empty()) ? static_cast<void> (0) : __assert_fail
("CurPath.empty()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 676, __PRETTY_FUNCTION__))
;
677 CurPath.push_back(Cur);
678 return findFriendship(Cur, 0);
679 }
680};
681}
682
683/// Search for a class P that EC is a friend of, under the constraint
684/// InstanceContext <= P
685/// if InstanceContext exists, or else
686/// NamingClass <= P
687/// and with the additional restriction that a protected member of
688/// NamingClass would have some natural access in P, which implicitly
689/// imposes the constraint that P <= NamingClass.
690///
691/// This isn't quite the condition laid out in the standard.
692/// Instead of saying that a notional protected member of NamingClass
693/// would have to have some natural access in P, it says the actual
694/// target has to have some natural access in P, which opens up the
695/// possibility that the target (which is not necessarily a member
696/// of NamingClass) might be more accessible along some path not
697/// passing through it. That's really a bad idea, though, because it
698/// introduces two problems:
699/// - Most importantly, it breaks encapsulation because you can
700/// access a forbidden base class's members by directly subclassing
701/// it elsewhere.
702/// - It also makes access substantially harder to compute because it
703/// breaks the hill-climbing algorithm: knowing that the target is
704/// accessible in some base class would no longer let you change
705/// the question solely to whether the base class is accessible,
706/// because the original target might have been more accessible
707/// because of crazy subclassing.
708/// So we don't implement that.
709static AccessResult GetProtectedFriendKind(Sema &S, const EffectiveContext &EC,
710 const CXXRecordDecl *InstanceContext,
711 const CXXRecordDecl *NamingClass) {
712 assert(InstanceContext == nullptr ||((InstanceContext == nullptr || InstanceContext->getCanonicalDecl
() == InstanceContext) ? static_cast<void> (0) : __assert_fail
("InstanceContext == nullptr || InstanceContext->getCanonicalDecl() == InstanceContext"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 713, __PRETTY_FUNCTION__))
713 InstanceContext->getCanonicalDecl() == InstanceContext)((InstanceContext == nullptr || InstanceContext->getCanonicalDecl
() == InstanceContext) ? static_cast<void> (0) : __assert_fail
("InstanceContext == nullptr || InstanceContext->getCanonicalDecl() == InstanceContext"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 713, __PRETTY_FUNCTION__))
;
714 assert(NamingClass->getCanonicalDecl() == NamingClass)((NamingClass->getCanonicalDecl() == NamingClass) ? static_cast
<void> (0) : __assert_fail ("NamingClass->getCanonicalDecl() == NamingClass"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 714, __PRETTY_FUNCTION__))
;
715
716 // If we don't have an instance context, our constraints give us
717 // that NamingClass <= P <= NamingClass, i.e. P == NamingClass.
718 // This is just the usual friendship check.
719 if (!InstanceContext) return GetFriendKind(S, EC, NamingClass);
720
721 ProtectedFriendContext PRC(S, EC, InstanceContext, NamingClass);
722 if (PRC.findFriendship(InstanceContext)) return AR_accessible;
723 if (PRC.EverDependent) return AR_dependent;
724 return AR_inaccessible;
725}
726
727static AccessResult HasAccess(Sema &S,
728 const EffectiveContext &EC,
729 const CXXRecordDecl *NamingClass,
730 AccessSpecifier Access,
731 const AccessTarget &Target) {
732 assert(NamingClass->getCanonicalDecl() == NamingClass &&((NamingClass->getCanonicalDecl() == NamingClass &&
"declaration should be canonicalized before being passed here"
) ? static_cast<void> (0) : __assert_fail ("NamingClass->getCanonicalDecl() == NamingClass && \"declaration should be canonicalized before being passed here\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 733, __PRETTY_FUNCTION__))
733 "declaration should be canonicalized before being passed here")((NamingClass->getCanonicalDecl() == NamingClass &&
"declaration should be canonicalized before being passed here"
) ? static_cast<void> (0) : __assert_fail ("NamingClass->getCanonicalDecl() == NamingClass && \"declaration should be canonicalized before being passed here\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 733, __PRETTY_FUNCTION__))
;
734
735 if (Access == AS_public) return AR_accessible;
736 assert(Access == AS_private || Access == AS_protected)((Access == AS_private || Access == AS_protected) ? static_cast
<void> (0) : __assert_fail ("Access == AS_private || Access == AS_protected"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 736, __PRETTY_FUNCTION__))
;
737
738 AccessResult OnFailure = AR_inaccessible;
739
740 for (EffectiveContext::record_iterator
741 I = EC.Records.begin(), E = EC.Records.end(); I != E; ++I) {
742 // All the declarations in EC have been canonicalized, so pointer
743 // equality from this point on will work fine.
744 const CXXRecordDecl *ECRecord = *I;
745
746 // [B2] and [M2]
747 if (Access == AS_private) {
748 if (ECRecord == NamingClass)
749 return AR_accessible;
750
751 if (EC.isDependent() && MightInstantiateTo(ECRecord, NamingClass))
752 OnFailure = AR_dependent;
753
754 // [B3] and [M3]
755 } else {
756 assert(Access == AS_protected)((Access == AS_protected) ? static_cast<void> (0) : __assert_fail
("Access == AS_protected", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 756, __PRETTY_FUNCTION__))
;
757 switch (IsDerivedFromInclusive(ECRecord, NamingClass)) {
758 case AR_accessible: break;
759 case AR_inaccessible: continue;
760 case AR_dependent: OnFailure = AR_dependent; continue;
761 }
762
763 // C++ [class.protected]p1:
764 // An additional access check beyond those described earlier in
765 // [class.access] is applied when a non-static data member or
766 // non-static member function is a protected member of its naming
767 // class. As described earlier, access to a protected member is
768 // granted because the reference occurs in a friend or member of
769 // some class C. If the access is to form a pointer to member,
770 // the nested-name-specifier shall name C or a class derived from
771 // C. All other accesses involve a (possibly implicit) object
772 // expression. In this case, the class of the object expression
773 // shall be C or a class derived from C.
774 //
775 // We interpret this as a restriction on [M3].
776
777 // In this part of the code, 'C' is just our context class ECRecord.
778
779 // These rules are different if we don't have an instance context.
780 if (!Target.hasInstanceContext()) {
781 // If it's not an instance member, these restrictions don't apply.
782 if (!Target.isInstanceMember()) return AR_accessible;
783
784 // If it's an instance member, use the pointer-to-member rule
785 // that the naming class has to be derived from the effective
786 // context.
787
788 // Emulate a MSVC bug where the creation of pointer-to-member
789 // to protected member of base class is allowed but only from
790 // static member functions.
791 if (S.getLangOpts().MSVCCompat && !EC.Functions.empty())
792 if (CXXMethodDecl* MD = dyn_cast<CXXMethodDecl>(EC.Functions.front()))
793 if (MD->isStatic()) return AR_accessible;
794
795 // Despite the standard's confident wording, there is a case
796 // where you can have an instance member that's neither in a
797 // pointer-to-member expression nor in a member access: when
798 // it names a field in an unevaluated context that can't be an
799 // implicit member. Pending clarification, we just apply the
800 // same naming-class restriction here.
801 // FIXME: we're probably not correctly adding the
802 // protected-member restriction when we retroactively convert
803 // an expression to being evaluated.
804
805 // We know that ECRecord derives from NamingClass. The
806 // restriction says to check whether NamingClass derives from
807 // ECRecord, but that's not really necessary: two distinct
808 // classes can't be recursively derived from each other. So
809 // along this path, we just need to check whether the classes
810 // are equal.
811 if (NamingClass == ECRecord) return AR_accessible;
812
813 // Otherwise, this context class tells us nothing; on to the next.
814 continue;
815 }
816
817 assert(Target.isInstanceMember())((Target.isInstanceMember()) ? static_cast<void> (0) : __assert_fail
("Target.isInstanceMember()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 817, __PRETTY_FUNCTION__))
;
818
819 const CXXRecordDecl *InstanceContext = Target.resolveInstanceContext(S);
820 if (!InstanceContext) {
821 OnFailure = AR_dependent;
822 continue;
823 }
824
825 switch (IsDerivedFromInclusive(InstanceContext, ECRecord)) {
826 case AR_accessible: return AR_accessible;
827 case AR_inaccessible: continue;
828 case AR_dependent: OnFailure = AR_dependent; continue;
829 }
830 }
831 }
832
833 // [M3] and [B3] say that, if the target is protected in N, we grant
834 // access if the access occurs in a friend or member of some class P
835 // that's a subclass of N and where the target has some natural
836 // access in P. The 'member' aspect is easy to handle because P
837 // would necessarily be one of the effective-context records, and we
838 // address that above. The 'friend' aspect is completely ridiculous
839 // to implement because there are no restrictions at all on P
840 // *unless* the [class.protected] restriction applies. If it does,
841 // however, we should ignore whether the naming class is a friend,
842 // and instead rely on whether any potential P is a friend.
843 if (Access == AS_protected && Target.isInstanceMember()) {
844 // Compute the instance context if possible.
845 const CXXRecordDecl *InstanceContext = nullptr;
846 if (Target.hasInstanceContext()) {
847 InstanceContext = Target.resolveInstanceContext(S);
848 if (!InstanceContext) return AR_dependent;
849 }
850
851 switch (GetProtectedFriendKind(S, EC, InstanceContext, NamingClass)) {
852 case AR_accessible: return AR_accessible;
853 case AR_inaccessible: return OnFailure;
854 case AR_dependent: return AR_dependent;
855 }
856 llvm_unreachable("impossible friendship kind")::llvm::llvm_unreachable_internal("impossible friendship kind"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 856)
;
857 }
858
859 switch (GetFriendKind(S, EC, NamingClass)) {
860 case AR_accessible: return AR_accessible;
861 case AR_inaccessible: return OnFailure;
862 case AR_dependent: return AR_dependent;
863 }
864
865 // Silence bogus warnings
866 llvm_unreachable("impossible friendship kind")::llvm::llvm_unreachable_internal("impossible friendship kind"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 866)
;
867}
868
869/// Finds the best path from the naming class to the declaring class,
870/// taking friend declarations into account.
871///
872/// C++0x [class.access.base]p5:
873/// A member m is accessible at the point R when named in class N if
874/// [M1] m as a member of N is public, or
875/// [M2] m as a member of N is private, and R occurs in a member or
876/// friend of class N, or
877/// [M3] m as a member of N is protected, and R occurs in a member or
878/// friend of class N, or in a member or friend of a class P
879/// derived from N, where m as a member of P is public, private,
880/// or protected, or
881/// [M4] there exists a base class B of N that is accessible at R, and
882/// m is accessible at R when named in class B.
883///
884/// C++0x [class.access.base]p4:
885/// A base class B of N is accessible at R, if
886/// [B1] an invented public member of B would be a public member of N, or
887/// [B2] R occurs in a member or friend of class N, and an invented public
888/// member of B would be a private or protected member of N, or
889/// [B3] R occurs in a member or friend of a class P derived from N, and an
890/// invented public member of B would be a private or protected member
891/// of P, or
892/// [B4] there exists a class S such that B is a base class of S accessible
893/// at R and S is a base class of N accessible at R.
894///
895/// Along a single inheritance path we can restate both of these
896/// iteratively:
897///
898/// First, we note that M1-4 are equivalent to B1-4 if the member is
899/// treated as a notional base of its declaring class with inheritance
900/// access equivalent to the member's access. Therefore we need only
901/// ask whether a class B is accessible from a class N in context R.
902///
903/// Let B_1 .. B_n be the inheritance path in question (i.e. where
904/// B_1 = N, B_n = B, and for all i, B_{i+1} is a direct base class of
905/// B_i). For i in 1..n, we will calculate ACAB(i), the access to the
906/// closest accessible base in the path:
907/// Access(a, b) = (* access on the base specifier from a to b *)
908/// Merge(a, forbidden) = forbidden
909/// Merge(a, private) = forbidden
910/// Merge(a, b) = min(a,b)
911/// Accessible(c, forbidden) = false
912/// Accessible(c, private) = (R is c) || IsFriend(c, R)
913/// Accessible(c, protected) = (R derived from c) || IsFriend(c, R)
914/// Accessible(c, public) = true
915/// ACAB(n) = public
916/// ACAB(i) =
917/// let AccessToBase = Merge(Access(B_i, B_{i+1}), ACAB(i+1)) in
918/// if Accessible(B_i, AccessToBase) then public else AccessToBase
919///
920/// B is an accessible base of N at R iff ACAB(1) = public.
921///
922/// \param FinalAccess the access of the "final step", or AS_public if
923/// there is no final step.
924/// \return null if friendship is dependent
925static CXXBasePath *FindBestPath(Sema &S,
926 const EffectiveContext &EC,
927 AccessTarget &Target,
928 AccessSpecifier FinalAccess,
929 CXXBasePaths &Paths) {
930 // Derive the paths to the desired base.
931 const CXXRecordDecl *Derived = Target.getNamingClass();
932 const CXXRecordDecl *Base = Target.getDeclaringClass();
933
934 // FIXME: fail correctly when there are dependent paths.
935 bool isDerived = Derived->isDerivedFrom(const_cast<CXXRecordDecl*>(Base),
936 Paths);
937 assert(isDerived && "derived class not actually derived from base")((isDerived && "derived class not actually derived from base"
) ? static_cast<void> (0) : __assert_fail ("isDerived && \"derived class not actually derived from base\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 937, __PRETTY_FUNCTION__))
;
938 (void) isDerived;
939
940 CXXBasePath *BestPath = nullptr;
941
942 assert(FinalAccess != AS_none && "forbidden access after declaring class")((FinalAccess != AS_none && "forbidden access after declaring class"
) ? static_cast<void> (0) : __assert_fail ("FinalAccess != AS_none && \"forbidden access after declaring class\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 942, __PRETTY_FUNCTION__))
;
943
944 bool AnyDependent = false;
945
946 // Derive the friend-modified access along each path.
947 for (CXXBasePaths::paths_iterator PI = Paths.begin(), PE = Paths.end();
948 PI != PE; ++PI) {
949 AccessTarget::SavedInstanceContext _ = Target.saveInstanceContext();
950
951 // Walk through the path backwards.
952 AccessSpecifier PathAccess = FinalAccess;
953 CXXBasePath::iterator I = PI->end(), E = PI->begin();
954 while (I != E) {
955 --I;
956
957 assert(PathAccess != AS_none)((PathAccess != AS_none) ? static_cast<void> (0) : __assert_fail
("PathAccess != AS_none", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 957, __PRETTY_FUNCTION__))
;
958
959 // If the declaration is a private member of a base class, there
960 // is no level of friendship in derived classes that can make it
961 // accessible.
962 if (PathAccess == AS_private) {
963 PathAccess = AS_none;
964 break;
965 }
966
967 const CXXRecordDecl *NC = I->Class->getCanonicalDecl();
968
969 AccessSpecifier BaseAccess = I->Base->getAccessSpecifier();
970 PathAccess = std::max(PathAccess, BaseAccess);
971
972 switch (HasAccess(S, EC, NC, PathAccess, Target)) {
973 case AR_inaccessible: break;
974 case AR_accessible:
975 PathAccess = AS_public;
976
977 // Future tests are not against members and so do not have
978 // instance context.
979 Target.suppressInstanceContext();
980 break;
981 case AR_dependent:
982 AnyDependent = true;
983 goto Next;
984 }
985 }
986
987 // Note that we modify the path's Access field to the
988 // friend-modified access.
989 if (BestPath == nullptr || PathAccess < BestPath->Access) {
990 BestPath = &*PI;
991 BestPath->Access = PathAccess;
992
993 // Short-circuit if we found a public path.
994 if (BestPath->Access == AS_public)
995 return BestPath;
996 }
997
998 Next: ;
999 }
1000
1001 assert((!BestPath || BestPath->Access != AS_public) &&(((!BestPath || BestPath->Access != AS_public) && "fell out of loop with public path"
) ? static_cast<void> (0) : __assert_fail ("(!BestPath || BestPath->Access != AS_public) && \"fell out of loop with public path\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1002, __PRETTY_FUNCTION__))
1002 "fell out of loop with public path")(((!BestPath || BestPath->Access != AS_public) && "fell out of loop with public path"
) ? static_cast<void> (0) : __assert_fail ("(!BestPath || BestPath->Access != AS_public) && \"fell out of loop with public path\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1002, __PRETTY_FUNCTION__))
;
1003
1004 // We didn't find a public path, but at least one path was subject
1005 // to dependent friendship, so delay the check.
1006 if (AnyDependent)
1007 return nullptr;
1008
1009 return BestPath;
1010}
1011
1012/// Given that an entity has protected natural access, check whether
1013/// access might be denied because of the protected member access
1014/// restriction.
1015///
1016/// \return true if a note was emitted
1017static bool TryDiagnoseProtectedAccess(Sema &S, const EffectiveContext &EC,
1018 AccessTarget &Target) {
1019 // Only applies to instance accesses.
1020 if (!Target.isInstanceMember())
1021 return false;
1022
1023 assert(Target.isMemberAccess())((Target.isMemberAccess()) ? static_cast<void> (0) : __assert_fail
("Target.isMemberAccess()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1023, __PRETTY_FUNCTION__))
;
1024
1025 const CXXRecordDecl *NamingClass = Target.getEffectiveNamingClass();
1026
1027 for (EffectiveContext::record_iterator
1028 I = EC.Records.begin(), E = EC.Records.end(); I != E; ++I) {
1029 const CXXRecordDecl *ECRecord = *I;
1030 switch (IsDerivedFromInclusive(ECRecord, NamingClass)) {
1031 case AR_accessible: break;
1032 case AR_inaccessible: continue;
1033 case AR_dependent: continue;
1034 }
1035
1036 // The effective context is a subclass of the declaring class.
1037 // Check whether the [class.protected] restriction is limiting
1038 // access.
1039
1040 // To get this exactly right, this might need to be checked more
1041 // holistically; it's not necessarily the case that gaining
1042 // access here would grant us access overall.
1043
1044 NamedDecl *D = Target.getTargetDecl();
1045
1046 // If we don't have an instance context, [class.protected] says the
1047 // naming class has to equal the context class.
1048 if (!Target.hasInstanceContext()) {
1049 // If it does, the restriction doesn't apply.
1050 if (NamingClass == ECRecord) continue;
1051
1052 // TODO: it would be great to have a fixit here, since this is
1053 // such an obvious error.
1054 S.Diag(D->getLocation(), diag::note_access_protected_restricted_noobject)
1055 << S.Context.getTypeDeclType(ECRecord);
1056 return true;
1057 }
1058
1059 const CXXRecordDecl *InstanceContext = Target.resolveInstanceContext(S);
1060 assert(InstanceContext && "diagnosing dependent access")((InstanceContext && "diagnosing dependent access") ?
static_cast<void> (0) : __assert_fail ("InstanceContext && \"diagnosing dependent access\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1060, __PRETTY_FUNCTION__))
;
1061
1062 switch (IsDerivedFromInclusive(InstanceContext, ECRecord)) {
1063 case AR_accessible: continue;
1064 case AR_dependent: continue;
1065 case AR_inaccessible:
1066 break;
1067 }
1068
1069 // Okay, the restriction seems to be what's limiting us.
1070
1071 // Use a special diagnostic for constructors and destructors.
1072 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D) ||
1073 (isa<FunctionTemplateDecl>(D) &&
1074 isa<CXXConstructorDecl>(
1075 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()))) {
1076 return S.Diag(D->getLocation(),
1077 diag::note_access_protected_restricted_ctordtor)
1078 << isa<CXXDestructorDecl>(D->getAsFunction());
1079 }
1080
1081 // Otherwise, use the generic diagnostic.
1082 return S.Diag(D->getLocation(),
1083 diag::note_access_protected_restricted_object)
1084 << S.Context.getTypeDeclType(ECRecord);
1085 }
1086
1087 return false;
1088}
1089
1090/// We are unable to access a given declaration due to its direct
1091/// access control; diagnose that.
1092static void diagnoseBadDirectAccess(Sema &S,
1093 const EffectiveContext &EC,
1094 AccessTarget &entity) {
1095 assert(entity.isMemberAccess())((entity.isMemberAccess()) ? static_cast<void> (0) : __assert_fail
("entity.isMemberAccess()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1095, __PRETTY_FUNCTION__))
;
1096 NamedDecl *D = entity.getTargetDecl();
1097
1098 if (D->getAccess() == AS_protected &&
1099 TryDiagnoseProtectedAccess(S, EC, entity))
1100 return;
1101
1102 // Find an original declaration.
1103 while (D->isOutOfLine()) {
1104 NamedDecl *PrevDecl = nullptr;
1105 if (VarDecl *VD = dyn_cast<VarDecl>(D))
1106 PrevDecl = VD->getPreviousDecl();
1107 else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
1108 PrevDecl = FD->getPreviousDecl();
1109 else if (TypedefNameDecl *TND = dyn_cast<TypedefNameDecl>(D))
1110 PrevDecl = TND->getPreviousDecl();
1111 else if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
1112 if (isa<RecordDecl>(D) && cast<RecordDecl>(D)->isInjectedClassName())
1113 break;
1114 PrevDecl = TD->getPreviousDecl();
1115 }
1116 if (!PrevDecl) break;
1117 D = PrevDecl;
1118 }
1119
1120 CXXRecordDecl *DeclaringClass = FindDeclaringClass(D);
1121 Decl *ImmediateChild;
1122 if (D->getDeclContext() == DeclaringClass)
1123 ImmediateChild = D;
1124 else {
1125 DeclContext *DC = D->getDeclContext();
1126 while (DC->getParent() != DeclaringClass)
1127 DC = DC->getParent();
1128 ImmediateChild = cast<Decl>(DC);
1129 }
1130
1131 // Check whether there's an AccessSpecDecl preceding this in the
1132 // chain of the DeclContext.
1133 bool isImplicit = true;
1134 for (const auto *I : DeclaringClass->decls()) {
1135 if (I == ImmediateChild) break;
1136 if (isa<AccessSpecDecl>(I)) {
1137 isImplicit = false;
1138 break;
1139 }
1140 }
1141
1142 S.Diag(D->getLocation(), diag::note_access_natural)
1143 << (unsigned) (D->getAccess() == AS_protected)
1144 << isImplicit;
1145}
1146
1147/// Diagnose the path which caused the given declaration or base class
1148/// to become inaccessible.
1149static void DiagnoseAccessPath(Sema &S,
1150 const EffectiveContext &EC,
1151 AccessTarget &entity) {
1152 // Save the instance context to preserve invariants.
1153 AccessTarget::SavedInstanceContext _ = entity.saveInstanceContext();
1154
1155 // This basically repeats the main algorithm but keeps some more
1156 // information.
1157
1158 // The natural access so far.
1159 AccessSpecifier accessSoFar = AS_public;
1160
1161 // Check whether we have special rights to the declaring class.
1162 if (entity.isMemberAccess()) {
1163 NamedDecl *D = entity.getTargetDecl();
1164 accessSoFar = D->getAccess();
1165 const CXXRecordDecl *declaringClass = entity.getDeclaringClass();
1166
1167 switch (HasAccess(S, EC, declaringClass, accessSoFar, entity)) {
1168 // If the declaration is accessible when named in its declaring
1169 // class, then we must be constrained by the path.
1170 case AR_accessible:
1171 accessSoFar = AS_public;
1172 entity.suppressInstanceContext();
1173 break;
1174
1175 case AR_inaccessible:
1176 if (accessSoFar == AS_private ||
1177 declaringClass == entity.getEffectiveNamingClass())
1178 return diagnoseBadDirectAccess(S, EC, entity);
1179 break;
1180
1181 case AR_dependent:
1182 llvm_unreachable("cannot diagnose dependent access")::llvm::llvm_unreachable_internal("cannot diagnose dependent access"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1182)
;
1183 }
1184 }
1185
1186 CXXBasePaths paths;
1187 CXXBasePath &path = *FindBestPath(S, EC, entity, accessSoFar, paths);
1188 assert(path.Access != AS_public)((path.Access != AS_public) ? static_cast<void> (0) : __assert_fail
("path.Access != AS_public", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1188, __PRETTY_FUNCTION__))
;
1189
1190 CXXBasePath::iterator i = path.end(), e = path.begin();
1191 CXXBasePath::iterator constrainingBase = i;
1192 while (i != e) {
1193 --i;
1194
1195 assert(accessSoFar != AS_none && accessSoFar != AS_private)((accessSoFar != AS_none && accessSoFar != AS_private
) ? static_cast<void> (0) : __assert_fail ("accessSoFar != AS_none && accessSoFar != AS_private"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1195, __PRETTY_FUNCTION__))
;
1196
1197 // Is the entity accessible when named in the deriving class, as
1198 // modified by the base specifier?
1199 const CXXRecordDecl *derivingClass = i->Class->getCanonicalDecl();
1200 const CXXBaseSpecifier *base = i->Base;
1201
1202 // If the access to this base is worse than the access we have to
1203 // the declaration, remember it.
1204 AccessSpecifier baseAccess = base->getAccessSpecifier();
1205 if (baseAccess > accessSoFar) {
1206 constrainingBase = i;
1207 accessSoFar = baseAccess;
1208 }
1209
1210 switch (HasAccess(S, EC, derivingClass, accessSoFar, entity)) {
1211 case AR_inaccessible: break;
1212 case AR_accessible:
1213 accessSoFar = AS_public;
1214 entity.suppressInstanceContext();
1215 constrainingBase = nullptr;
1216 break;
1217 case AR_dependent:
1218 llvm_unreachable("cannot diagnose dependent access")::llvm::llvm_unreachable_internal("cannot diagnose dependent access"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1218)
;
1219 }
1220
1221 // If this was private inheritance, but we don't have access to
1222 // the deriving class, we're done.
1223 if (accessSoFar == AS_private) {
1224 assert(baseAccess == AS_private)((baseAccess == AS_private) ? static_cast<void> (0) : __assert_fail
("baseAccess == AS_private", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1224, __PRETTY_FUNCTION__))
;
1225 assert(constrainingBase == i)((constrainingBase == i) ? static_cast<void> (0) : __assert_fail
("constrainingBase == i", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1225, __PRETTY_FUNCTION__))
;
1226 break;
1227 }
1228 }
1229
1230 // If we don't have a constraining base, the access failure must be
1231 // due to the original declaration.
1232 if (constrainingBase == path.end())
1233 return diagnoseBadDirectAccess(S, EC, entity);
1234
1235 // We're constrained by inheritance, but we want to say
1236 // "declared private here" if we're diagnosing a hierarchy
1237 // conversion and this is the final step.
1238 unsigned diagnostic;
1239 if (entity.isMemberAccess() ||
1240 constrainingBase + 1 != path.end()) {
1241 diagnostic = diag::note_access_constrained_by_path;
1242 } else {
1243 diagnostic = diag::note_access_natural;
1244 }
1245
1246 const CXXBaseSpecifier *base = constrainingBase->Base;
1247
1248 S.Diag(base->getSourceRange().getBegin(), diagnostic)
1249 << base->getSourceRange()
1250 << (base->getAccessSpecifier() == AS_protected)
1251 << (base->getAccessSpecifierAsWritten() == AS_none);
1252
1253 if (entity.isMemberAccess())
1254 S.Diag(entity.getTargetDecl()->getLocation(),
1255 diag::note_member_declared_at);
1256}
1257
1258static void DiagnoseBadAccess(Sema &S, SourceLocation Loc,
1259 const EffectiveContext &EC,
1260 AccessTarget &Entity) {
1261 const CXXRecordDecl *NamingClass = Entity.getNamingClass();
1262 const CXXRecordDecl *DeclaringClass = Entity.getDeclaringClass();
1263 NamedDecl *D = (Entity.isMemberAccess() ? Entity.getTargetDecl() : nullptr);
1264
1265 S.Diag(Loc, Entity.getDiag())
1266 << (Entity.getAccess() == AS_protected)
1267 << (D ? D->getDeclName() : DeclarationName())
1268 << S.Context.getTypeDeclType(NamingClass)
1269 << S.Context.getTypeDeclType(DeclaringClass);
1270 DiagnoseAccessPath(S, EC, Entity);
1271}
1272
1273/// MSVC has a bug where if during an using declaration name lookup,
1274/// the declaration found is unaccessible (private) and that declaration
1275/// was bring into scope via another using declaration whose target
1276/// declaration is accessible (public) then no error is generated.
1277/// Example:
1278/// class A {
1279/// public:
1280/// int f();
1281/// };
1282/// class B : public A {
1283/// private:
1284/// using A::f;
1285/// };
1286/// class C : public B {
1287/// private:
1288/// using B::f;
1289/// };
1290///
1291/// Here, B::f is private so this should fail in Standard C++, but
1292/// because B::f refers to A::f which is public MSVC accepts it.
1293static bool IsMicrosoftUsingDeclarationAccessBug(Sema& S,
1294 SourceLocation AccessLoc,
1295 AccessTarget &Entity) {
1296 if (UsingShadowDecl *Shadow =
1297 dyn_cast<UsingShadowDecl>(Entity.getTargetDecl())) {
1298 const NamedDecl *OrigDecl = Entity.getTargetDecl()->getUnderlyingDecl();
1299 if (Entity.getTargetDecl()->getAccess() == AS_private &&
1300 (OrigDecl->getAccess() == AS_public ||
1301 OrigDecl->getAccess() == AS_protected)) {
1302 S.Diag(AccessLoc, diag::ext_ms_using_declaration_inaccessible)
1303 << Shadow->getUsingDecl()->getQualifiedNameAsString()
1304 << OrigDecl->getQualifiedNameAsString();
1305 return true;
1306 }
1307 }
1308 return false;
1309}
1310
1311/// Determines whether the accessed entity is accessible. Public members
1312/// have been weeded out by this point.
1313static AccessResult IsAccessible(Sema &S,
1314 const EffectiveContext &EC,
1315 AccessTarget &Entity) {
1316 // Determine the actual naming class.
1317 const CXXRecordDecl *NamingClass = Entity.getEffectiveNamingClass();
1318
1319 AccessSpecifier UnprivilegedAccess = Entity.getAccess();
1320 assert(UnprivilegedAccess != AS_public && "public access not weeded out")((UnprivilegedAccess != AS_public && "public access not weeded out"
) ? static_cast<void> (0) : __assert_fail ("UnprivilegedAccess != AS_public && \"public access not weeded out\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1320, __PRETTY_FUNCTION__))
;
1321
1322 // Before we try to recalculate access paths, try to white-list
1323 // accesses which just trade in on the final step, i.e. accesses
1324 // which don't require [M4] or [B4]. These are by far the most
1325 // common forms of privileged access.
1326 if (UnprivilegedAccess != AS_none) {
1327 switch (HasAccess(S, EC, NamingClass, UnprivilegedAccess, Entity)) {
1328 case AR_dependent:
1329 // This is actually an interesting policy decision. We don't
1330 // *have* to delay immediately here: we can do the full access
1331 // calculation in the hope that friendship on some intermediate
1332 // class will make the declaration accessible non-dependently.
1333 // But that's not cheap, and odds are very good (note: assertion
1334 // made without data) that the friend declaration will determine
1335 // access.
1336 return AR_dependent;
1337
1338 case AR_accessible: return AR_accessible;
1339 case AR_inaccessible: break;
1340 }
1341 }
1342
1343 AccessTarget::SavedInstanceContext _ = Entity.saveInstanceContext();
1344
1345 // We lower member accesses to base accesses by pretending that the
1346 // member is a base class of its declaring class.
1347 AccessSpecifier FinalAccess;
1348
1349 if (Entity.isMemberAccess()) {
1350 // Determine if the declaration is accessible from EC when named
1351 // in its declaring class.
1352 NamedDecl *Target = Entity.getTargetDecl();
1353 const CXXRecordDecl *DeclaringClass = Entity.getDeclaringClass();
1354
1355 FinalAccess = Target->getAccess();
1356 switch (HasAccess(S, EC, DeclaringClass, FinalAccess, Entity)) {
1357 case AR_accessible:
1358 // Target is accessible at EC when named in its declaring class.
1359 // We can now hill-climb and simply check whether the declaring
1360 // class is accessible as a base of the naming class. This is
1361 // equivalent to checking the access of a notional public
1362 // member with no instance context.
1363 FinalAccess = AS_public;
1364 Entity.suppressInstanceContext();
1365 break;
1366 case AR_inaccessible: break;
1367 case AR_dependent: return AR_dependent; // see above
1368 }
1369
1370 if (DeclaringClass == NamingClass)
1371 return (FinalAccess == AS_public ? AR_accessible : AR_inaccessible);
1372 } else {
1373 FinalAccess = AS_public;
1374 }
1375
1376 assert(Entity.getDeclaringClass() != NamingClass)((Entity.getDeclaringClass() != NamingClass) ? static_cast<
void> (0) : __assert_fail ("Entity.getDeclaringClass() != NamingClass"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1376, __PRETTY_FUNCTION__))
;
1377
1378 // Append the declaration's access if applicable.
1379 CXXBasePaths Paths;
1380 CXXBasePath *Path = FindBestPath(S, EC, Entity, FinalAccess, Paths);
1381 if (!Path)
1382 return AR_dependent;
1383
1384 assert(Path->Access <= UnprivilegedAccess &&((Path->Access <= UnprivilegedAccess && "access along best path worse than direct?"
) ? static_cast<void> (0) : __assert_fail ("Path->Access <= UnprivilegedAccess && \"access along best path worse than direct?\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1385, __PRETTY_FUNCTION__))
1385 "access along best path worse than direct?")((Path->Access <= UnprivilegedAccess && "access along best path worse than direct?"
) ? static_cast<void> (0) : __assert_fail ("Path->Access <= UnprivilegedAccess && \"access along best path worse than direct?\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1385, __PRETTY_FUNCTION__))
;
1386 if (Path->Access == AS_public)
1387 return AR_accessible;
1388 return AR_inaccessible;
1389}
1390
1391static void DelayDependentAccess(Sema &S,
1392 const EffectiveContext &EC,
1393 SourceLocation Loc,
1394 const AccessTarget &Entity) {
1395 assert(EC.isDependent() && "delaying non-dependent access")((EC.isDependent() && "delaying non-dependent access"
) ? static_cast<void> (0) : __assert_fail ("EC.isDependent() && \"delaying non-dependent access\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1395, __PRETTY_FUNCTION__))
;
1396 DeclContext *DC = EC.getInnerContext();
1397 assert(DC->isDependentContext() && "delaying non-dependent access")((DC->isDependentContext() && "delaying non-dependent access"
) ? static_cast<void> (0) : __assert_fail ("DC->isDependentContext() && \"delaying non-dependent access\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1397, __PRETTY_FUNCTION__))
;
1398 DependentDiagnostic::Create(S.Context, DC, DependentDiagnostic::Access,
1399 Loc,
1400 Entity.isMemberAccess(),
1401 Entity.getAccess(),
1402 Entity.getTargetDecl(),
1403 Entity.getNamingClass(),
1404 Entity.getBaseObjectType(),
1405 Entity.getDiag());
1406}
1407
1408/// Checks access to an entity from the given effective context.
1409static AccessResult CheckEffectiveAccess(Sema &S,
1410 const EffectiveContext &EC,
1411 SourceLocation Loc,
1412 AccessTarget &Entity) {
1413 assert(Entity.getAccess() != AS_public && "called for public access!")((Entity.getAccess() != AS_public && "called for public access!"
) ? static_cast<void> (0) : __assert_fail ("Entity.getAccess() != AS_public && \"called for public access!\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1413, __PRETTY_FUNCTION__))
;
1414
1415 switch (IsAccessible(S, EC, Entity)) {
1416 case AR_dependent:
1417 DelayDependentAccess(S, EC, Loc, Entity);
1418 return AR_dependent;
1419
1420 case AR_inaccessible:
1421 if (S.getLangOpts().MSVCCompat &&
1422 IsMicrosoftUsingDeclarationAccessBug(S, Loc, Entity))
1423 return AR_accessible;
1424 if (!Entity.isQuiet())
1425 DiagnoseBadAccess(S, Loc, EC, Entity);
1426 return AR_inaccessible;
1427
1428 case AR_accessible:
1429 return AR_accessible;
1430 }
1431
1432 // silence unnecessary warning
1433 llvm_unreachable("invalid access result")::llvm::llvm_unreachable_internal("invalid access result", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1433)
;
1434}
1435
1436static Sema::AccessResult CheckAccess(Sema &S, SourceLocation Loc,
1437 AccessTarget &Entity) {
1438 // If the access path is public, it's accessible everywhere.
1439 if (Entity.getAccess() == AS_public)
1440 return Sema::AR_accessible;
1441
1442 // If we're currently parsing a declaration, we may need to delay
1443 // access control checking, because our effective context might be
1444 // different based on what the declaration comes out as.
1445 //
1446 // For example, we might be parsing a declaration with a scope
1447 // specifier, like this:
1448 // A::private_type A::foo() { ... }
1449 //
1450 // Or we might be parsing something that will turn out to be a friend:
1451 // void foo(A::private_type);
1452 // void B::foo(A::private_type);
1453 if (S.DelayedDiagnostics.shouldDelayDiagnostics()) {
1454 S.DelayedDiagnostics.add(DelayedDiagnostic::makeAccess(Loc, Entity));
1455 return Sema::AR_delayed;
1456 }
1457
1458 EffectiveContext EC(S.CurContext);
1459 switch (CheckEffectiveAccess(S, EC, Loc, Entity)) {
1460 case AR_accessible: return Sema::AR_accessible;
1461 case AR_inaccessible: return Sema::AR_inaccessible;
1462 case AR_dependent: return Sema::AR_dependent;
1463 }
1464 llvm_unreachable("invalid access result")::llvm::llvm_unreachable_internal("invalid access result", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1464)
;
1465}
1466
1467void Sema::HandleDelayedAccessCheck(DelayedDiagnostic &DD, Decl *D) {
1468 // Access control for names used in the declarations of functions
1469 // and function templates should normally be evaluated in the context
1470 // of the declaration, just in case it's a friend of something.
1471 // However, this does not apply to local extern declarations.
1472
1473 DeclContext *DC = D->getDeclContext();
1474 if (D->isLocalExternDecl()) {
1475 DC = D->getLexicalDeclContext();
1476 } else if (FunctionDecl *FN = dyn_cast<FunctionDecl>(D)) {
1477 DC = FN;
1478 } else if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D)) {
1479 DC = cast<DeclContext>(TD->getTemplatedDecl());
1480 }
1481
1482 EffectiveContext EC(DC);
1483
1484 AccessTarget Target(DD.getAccessData());
1485
1486 if (CheckEffectiveAccess(*this, EC, DD.Loc, Target) == ::AR_inaccessible)
1487 DD.Triggered = true;
1488}
1489
1490void Sema::HandleDependentAccessCheck(const DependentDiagnostic &DD,
1491 const MultiLevelTemplateArgumentList &TemplateArgs) {
1492 SourceLocation Loc = DD.getAccessLoc();
1493 AccessSpecifier Access = DD.getAccess();
1494
1495 Decl *NamingD = FindInstantiatedDecl(Loc, DD.getAccessNamingClass(),
1496 TemplateArgs);
1497 if (!NamingD) return;
1498 Decl *TargetD = FindInstantiatedDecl(Loc, DD.getAccessTarget(),
1499 TemplateArgs);
1500 if (!TargetD) return;
1501
1502 if (DD.isAccessToMember()) {
1503 CXXRecordDecl *NamingClass = cast<CXXRecordDecl>(NamingD);
1504 NamedDecl *TargetDecl = cast<NamedDecl>(TargetD);
1505 QualType BaseObjectType = DD.getAccessBaseObjectType();
1506 if (!BaseObjectType.isNull()) {
1507 BaseObjectType = SubstType(BaseObjectType, TemplateArgs, Loc,
1508 DeclarationName());
1509 if (BaseObjectType.isNull()) return;
1510 }
1511
1512 AccessTarget Entity(Context,
1513 AccessTarget::Member,
1514 NamingClass,
1515 DeclAccessPair::make(TargetDecl, Access),
1516 BaseObjectType);
1517 Entity.setDiag(DD.getDiagnostic());
1518 CheckAccess(*this, Loc, Entity);
1519 } else {
1520 AccessTarget Entity(Context,
1521 AccessTarget::Base,
1522 cast<CXXRecordDecl>(TargetD),
1523 cast<CXXRecordDecl>(NamingD),
1524 Access);
1525 Entity.setDiag(DD.getDiagnostic());
1526 CheckAccess(*this, Loc, Entity);
1527 }
1528}
1529
1530Sema::AccessResult Sema::CheckUnresolvedLookupAccess(UnresolvedLookupExpr *E,
1531 DeclAccessPair Found) {
1532 if (!getLangOpts().AccessControl ||
1533 !E->getNamingClass() ||
1534 Found.getAccess() == AS_public)
1535 return AR_accessible;
1536
1537 AccessTarget Entity(Context, AccessTarget::Member, E->getNamingClass(),
1538 Found, QualType());
1539 Entity.setDiag(diag::err_access) << E->getSourceRange();
1540
1541 return CheckAccess(*this, E->getNameLoc(), Entity);
1542}
1543
1544/// Perform access-control checking on a previously-unresolved member
1545/// access which has now been resolved to a member.
1546Sema::AccessResult Sema::CheckUnresolvedMemberAccess(UnresolvedMemberExpr *E,
1547 DeclAccessPair Found) {
1548 if (!getLangOpts().AccessControl ||
1
Assuming field 'AccessControl' is not equal to 0
3
Taking false branch
1549 Found.getAccess() == AS_public)
2
Assuming the condition is false
1550 return AR_accessible;
1551
1552 QualType BaseType = E->getBaseType();
1553 if (E->isArrow())
4
Assuming the condition is true
5
Taking true branch
1554 BaseType = BaseType->getAs<PointerType>()->getPointeeType();
6
Assuming the object is not a 'PointerType'
7
Called C++ object pointer is null
1555
1556 AccessTarget Entity(Context, AccessTarget::Member, E->getNamingClass(),
1557 Found, BaseType);
1558 Entity.setDiag(diag::err_access) << E->getSourceRange();
1559
1560 return CheckAccess(*this, E->getMemberLoc(), Entity);
1561}
1562
1563/// Is the given special member function accessible for the purposes of
1564/// deciding whether to define a special member function as deleted?
1565bool Sema::isSpecialMemberAccessibleForDeletion(CXXMethodDecl *decl,
1566 AccessSpecifier access,
1567 QualType objectType) {
1568 // Fast path.
1569 if (access == AS_public || !getLangOpts().AccessControl) return true;
1570
1571 AccessTarget entity(Context, AccessTarget::Member, decl->getParent(),
1572 DeclAccessPair::make(decl, access), objectType);
1573
1574 // Suppress diagnostics.
1575 entity.setDiag(PDiag());
1576
1577 switch (CheckAccess(*this, SourceLocation(), entity)) {
1578 case AR_accessible: return true;
1579 case AR_inaccessible: return false;
1580 case AR_dependent: llvm_unreachable("dependent for =delete computation")::llvm::llvm_unreachable_internal("dependent for =delete computation"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1580)
;
1581 case AR_delayed: llvm_unreachable("cannot delay =delete computation")::llvm::llvm_unreachable_internal("cannot delay =delete computation"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1581)
;
1582 }
1583 llvm_unreachable("bad access result")::llvm::llvm_unreachable_internal("bad access result", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1583)
;
1584}
1585
1586Sema::AccessResult Sema::CheckDestructorAccess(SourceLocation Loc,
1587 CXXDestructorDecl *Dtor,
1588 const PartialDiagnostic &PDiag,
1589 QualType ObjectTy) {
1590 if (!getLangOpts().AccessControl)
1591 return AR_accessible;
1592
1593 // There's never a path involved when checking implicit destructor access.
1594 AccessSpecifier Access = Dtor->getAccess();
1595 if (Access == AS_public)
1596 return AR_accessible;
1597
1598 CXXRecordDecl *NamingClass = Dtor->getParent();
1599 if (ObjectTy.isNull()) ObjectTy = Context.getTypeDeclType(NamingClass);
1600
1601 AccessTarget Entity(Context, AccessTarget::Member, NamingClass,
1602 DeclAccessPair::make(Dtor, Access),
1603 ObjectTy);
1604 Entity.setDiag(PDiag); // TODO: avoid copy
1605
1606 return CheckAccess(*this, Loc, Entity);
1607}
1608
1609/// Checks access to a constructor.
1610Sema::AccessResult Sema::CheckConstructorAccess(SourceLocation UseLoc,
1611 CXXConstructorDecl *Constructor,
1612 DeclAccessPair Found,
1613 const InitializedEntity &Entity,
1614 bool IsCopyBindingRefToTemp) {
1615 if (!getLangOpts().AccessControl || Found.getAccess() == AS_public)
1616 return AR_accessible;
1617
1618 PartialDiagnostic PD(PDiag());
1619 switch (Entity.getKind()) {
1620 default:
1621 PD = PDiag(IsCopyBindingRefToTemp
1622 ? diag::ext_rvalue_to_reference_access_ctor
1623 : diag::err_access_ctor);
1624
1625 break;
1626
1627 case InitializedEntity::EK_Base:
1628 PD = PDiag(diag::err_access_base_ctor);
1629 PD << Entity.isInheritedVirtualBase()
1630 << Entity.getBaseSpecifier()->getType() << getSpecialMember(Constructor);
1631 break;
1632
1633 case InitializedEntity::EK_Member: {
1634 const FieldDecl *Field = cast<FieldDecl>(Entity.getDecl());
1635 PD = PDiag(diag::err_access_field_ctor);
1636 PD << Field->getType() << getSpecialMember(Constructor);
1637 break;
1638 }
1639
1640 case InitializedEntity::EK_LambdaCapture: {
1641 StringRef VarName = Entity.getCapturedVarName();
1642 PD = PDiag(diag::err_access_lambda_capture);
1643 PD << VarName << Entity.getType() << getSpecialMember(Constructor);
1644 break;
1645 }
1646
1647 }
1648
1649 return CheckConstructorAccess(UseLoc, Constructor, Found, Entity, PD);
1650}
1651
1652/// Checks access to a constructor.
1653Sema::AccessResult Sema::CheckConstructorAccess(SourceLocation UseLoc,
1654 CXXConstructorDecl *Constructor,
1655 DeclAccessPair Found,
1656 const InitializedEntity &Entity,
1657 const PartialDiagnostic &PD) {
1658 if (!getLangOpts().AccessControl ||
1659 Found.getAccess() == AS_public)
1660 return AR_accessible;
1661
1662 CXXRecordDecl *NamingClass = Constructor->getParent();
1663
1664 // Initializing a base sub-object is an instance method call on an
1665 // object of the derived class. Otherwise, we have an instance method
1666 // call on an object of the constructed type.
1667 //
1668 // FIXME: If we have a parent, we're initializing the base class subobject
1669 // in aggregate initialization. It's not clear whether the object class
1670 // should be the base class or the derived class in that case.
1671 CXXRecordDecl *ObjectClass;
1672 if ((Entity.getKind() == InitializedEntity::EK_Base ||
1673 Entity.getKind() == InitializedEntity::EK_Delegating) &&
1674 !Entity.getParent()) {
1675 ObjectClass = cast<CXXConstructorDecl>(CurContext)->getParent();
1676 } else if (auto *Shadow =
1677 dyn_cast<ConstructorUsingShadowDecl>(Found.getDecl())) {
1678 // If we're using an inheriting constructor to construct an object,
1679 // the object class is the derived class, not the base class.
1680 ObjectClass = Shadow->getParent();
1681 } else {
1682 ObjectClass = NamingClass;
1683 }
1684
1685 AccessTarget AccessEntity(
1686 Context, AccessTarget::Member, NamingClass,
1687 DeclAccessPair::make(Constructor, Found.getAccess()),
1688 Context.getTypeDeclType(ObjectClass));
1689 AccessEntity.setDiag(PD);
1690
1691 return CheckAccess(*this, UseLoc, AccessEntity);
1692}
1693
1694/// Checks access to an overloaded operator new or delete.
1695Sema::AccessResult Sema::CheckAllocationAccess(SourceLocation OpLoc,
1696 SourceRange PlacementRange,
1697 CXXRecordDecl *NamingClass,
1698 DeclAccessPair Found,
1699 bool Diagnose) {
1700 if (!getLangOpts().AccessControl ||
1701 !NamingClass ||
1702 Found.getAccess() == AS_public)
1703 return AR_accessible;
1704
1705 AccessTarget Entity(Context, AccessTarget::Member, NamingClass, Found,
1706 QualType());
1707 if (Diagnose)
1708 Entity.setDiag(diag::err_access)
1709 << PlacementRange;
1710
1711 return CheckAccess(*this, OpLoc, Entity);
1712}
1713
1714/// Checks access to a member.
1715Sema::AccessResult Sema::CheckMemberAccess(SourceLocation UseLoc,
1716 CXXRecordDecl *NamingClass,
1717 DeclAccessPair Found) {
1718 if (!getLangOpts().AccessControl ||
1719 !NamingClass ||
1720 Found.getAccess() == AS_public)
1721 return AR_accessible;
1722
1723 AccessTarget Entity(Context, AccessTarget::Member, NamingClass,
1724 Found, QualType());
1725
1726 return CheckAccess(*this, UseLoc, Entity);
1727}
1728
1729/// Checks implicit access to a member in a structured binding.
1730Sema::AccessResult
1731Sema::CheckStructuredBindingMemberAccess(SourceLocation UseLoc,
1732 CXXRecordDecl *DecomposedClass,
1733 DeclAccessPair Field) {
1734 if (!getLangOpts().AccessControl ||
1735 Field.getAccess() == AS_public)
1736 return AR_accessible;
1737
1738 AccessTarget Entity(Context, AccessTarget::Member, DecomposedClass, Field,
1739 Context.getRecordType(DecomposedClass));
1740 Entity.setDiag(diag::err_decomp_decl_inaccessible_field);
1741
1742 return CheckAccess(*this, UseLoc, Entity);
1743}
1744
1745/// Checks access to an overloaded member operator, including
1746/// conversion operators.
1747Sema::AccessResult Sema::CheckMemberOperatorAccess(SourceLocation OpLoc,
1748 Expr *ObjectExpr,
1749 Expr *ArgExpr,
1750 DeclAccessPair Found) {
1751 if (!getLangOpts().AccessControl ||
1752 Found.getAccess() == AS_public)
1753 return AR_accessible;
1754
1755 const RecordType *RT = ObjectExpr->getType()->castAs<RecordType>();
1756 CXXRecordDecl *NamingClass = cast<CXXRecordDecl>(RT->getDecl());
1757
1758 AccessTarget Entity(Context, AccessTarget::Member, NamingClass, Found,
1759 ObjectExpr->getType());
1760 Entity.setDiag(diag::err_access)
1761 << ObjectExpr->getSourceRange()
1762 << (ArgExpr ? ArgExpr->getSourceRange() : SourceRange());
1763
1764 return CheckAccess(*this, OpLoc, Entity);
1765}
1766
1767/// Checks access to the target of a friend declaration.
1768Sema::AccessResult Sema::CheckFriendAccess(NamedDecl *target) {
1769 assert(isa<CXXMethodDecl>(target->getAsFunction()))((isa<CXXMethodDecl>(target->getAsFunction())) ? static_cast
<void> (0) : __assert_fail ("isa<CXXMethodDecl>(target->getAsFunction())"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1769, __PRETTY_FUNCTION__))
;
1770
1771 // Friendship lookup is a redeclaration lookup, so there's never an
1772 // inheritance path modifying access.
1773 AccessSpecifier access = target->getAccess();
1774
1775 if (!getLangOpts().AccessControl || access == AS_public)
1776 return AR_accessible;
1777
1778 CXXMethodDecl *method = cast<CXXMethodDecl>(target->getAsFunction());
1779
1780 AccessTarget entity(Context, AccessTarget::Member,
1781 cast<CXXRecordDecl>(target->getDeclContext()),
1782 DeclAccessPair::make(target, access),
1783 /*no instance context*/ QualType());
1784 entity.setDiag(diag::err_access_friend_function)
1785 << (method->getQualifier() ? method->getQualifierLoc().getSourceRange()
1786 : method->getNameInfo().getSourceRange());
1787
1788 // We need to bypass delayed-diagnostics because we might be called
1789 // while the ParsingDeclarator is active.
1790 EffectiveContext EC(CurContext);
1791 switch (CheckEffectiveAccess(*this, EC, target->getLocation(), entity)) {
1792 case ::AR_accessible: return Sema::AR_accessible;
1793 case ::AR_inaccessible: return Sema::AR_inaccessible;
1794 case ::AR_dependent: return Sema::AR_dependent;
1795 }
1796 llvm_unreachable("invalid access result")::llvm::llvm_unreachable_internal("invalid access result", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1796)
;
1797}
1798
1799Sema::AccessResult Sema::CheckAddressOfMemberAccess(Expr *OvlExpr,
1800 DeclAccessPair Found) {
1801 if (!getLangOpts().AccessControl ||
1802 Found.getAccess() == AS_none ||
1803 Found.getAccess() == AS_public)
1804 return AR_accessible;
1805
1806 OverloadExpr *Ovl = OverloadExpr::find(OvlExpr).Expression;
1807 CXXRecordDecl *NamingClass = Ovl->getNamingClass();
1808
1809 AccessTarget Entity(Context, AccessTarget::Member, NamingClass, Found,
1810 /*no instance context*/ QualType());
1811 Entity.setDiag(diag::err_access)
1812 << Ovl->getSourceRange();
1813
1814 return CheckAccess(*this, Ovl->getNameLoc(), Entity);
1815}
1816
1817/// Checks access for a hierarchy conversion.
1818///
1819/// \param ForceCheck true if this check should be performed even if access
1820/// control is disabled; some things rely on this for semantics
1821/// \param ForceUnprivileged true if this check should proceed as if the
1822/// context had no special privileges
1823Sema::AccessResult Sema::CheckBaseClassAccess(SourceLocation AccessLoc,
1824 QualType Base,
1825 QualType Derived,
1826 const CXXBasePath &Path,
1827 unsigned DiagID,
1828 bool ForceCheck,
1829 bool ForceUnprivileged) {
1830 if (!ForceCheck && !getLangOpts().AccessControl)
1831 return AR_accessible;
1832
1833 if (Path.Access == AS_public)
1834 return AR_accessible;
1835
1836 CXXRecordDecl *BaseD, *DerivedD;
1837 BaseD = cast<CXXRecordDecl>(Base->getAs<RecordType>()->getDecl());
1838 DerivedD = cast<CXXRecordDecl>(Derived->getAs<RecordType>()->getDecl());
1839
1840 AccessTarget Entity(Context, AccessTarget::Base, BaseD, DerivedD,
1841 Path.Access);
1842 if (DiagID)
1843 Entity.setDiag(DiagID) << Derived << Base;
1844
1845 if (ForceUnprivileged) {
1846 switch (CheckEffectiveAccess(*this, EffectiveContext(),
1847 AccessLoc, Entity)) {
1848 case ::AR_accessible: return Sema::AR_accessible;
1849 case ::AR_inaccessible: return Sema::AR_inaccessible;
1850 case ::AR_dependent: return Sema::AR_dependent;
1851 }
1852 llvm_unreachable("unexpected result from CheckEffectiveAccess")::llvm::llvm_unreachable_internal("unexpected result from CheckEffectiveAccess"
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1852)
;
1853 }
1854 return CheckAccess(*this, AccessLoc, Entity);
1855}
1856
1857/// Checks access to all the declarations in the given result set.
1858void Sema::CheckLookupAccess(const LookupResult &R) {
1859 assert(getLangOpts().AccessControl((getLangOpts().AccessControl && "performing access check without access control"
) ? static_cast<void> (0) : __assert_fail ("getLangOpts().AccessControl && \"performing access check without access control\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1860, __PRETTY_FUNCTION__))
1860 && "performing access check without access control")((getLangOpts().AccessControl && "performing access check without access control"
) ? static_cast<void> (0) : __assert_fail ("getLangOpts().AccessControl && \"performing access check without access control\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1860, __PRETTY_FUNCTION__))
;
1861 assert(R.getNamingClass() && "performing access check without naming class")((R.getNamingClass() && "performing access check without naming class"
) ? static_cast<void> (0) : __assert_fail ("R.getNamingClass() && \"performing access check without naming class\""
, "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/Sema/SemaAccess.cpp"
, 1861, __PRETTY_FUNCTION__))
;
1862
1863 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
1864 if (I.getAccess() != AS_public) {
1865 AccessTarget Entity(Context, AccessedEntity::Member,
1866 R.getNamingClass(), I.getPair(),
1867 R.getBaseObjectType());
1868 Entity.setDiag(diag::err_access);
1869 CheckAccess(*this, R.getNameLoc(), Entity);
1870 }
1871 }
1872}
1873
1874/// Checks access to Target from the given class. The check will take access
1875/// specifiers into account, but no member access expressions and such.
1876///
1877/// \param Target the declaration to check if it can be accessed
1878/// \param NamingClass the class in which the lookup was started.
1879/// \param BaseType type of the left side of member access expression.
1880/// \p BaseType and \p NamingClass are used for C++ access control.
1881/// Depending on the lookup case, they should be set to the following:
1882/// - lhs.target (member access without a qualifier):
1883/// \p BaseType and \p NamingClass are both the type of 'lhs'.
1884/// - lhs.X::target (member access with a qualifier):
1885/// BaseType is the type of 'lhs', NamingClass is 'X'
1886/// - X::target (qualified lookup without member access):
1887/// BaseType is null, NamingClass is 'X'.
1888/// - target (unqualified lookup).
1889/// BaseType is null, NamingClass is the parent class of 'target'.
1890/// \return true if the Target is accessible from the Class, false otherwise.
1891bool Sema::IsSimplyAccessible(NamedDecl *Target, CXXRecordDecl *NamingClass,
1892 QualType BaseType) {
1893 // Perform the C++ accessibility checks first.
1894 if (Target->isCXXClassMember() && NamingClass) {
1895 if (!getLangOpts().CPlusPlus)
1896 return false;
1897 // The unprivileged access is AS_none as we don't know how the member was
1898 // accessed, which is described by the access in DeclAccessPair.
1899 // `IsAccessible` will examine the actual access of Target (i.e.
1900 // Decl->getAccess()) when calculating the access.
1901 AccessTarget Entity(Context, AccessedEntity::Member, NamingClass,
1902 DeclAccessPair::make(Target, AS_none), BaseType);
1903 EffectiveContext EC(CurContext);
1904 return ::IsAccessible(*this, EC, Entity) != ::AR_inaccessible;
1905 }
1906
1907 if (ObjCIvarDecl *Ivar = dyn_cast<ObjCIvarDecl>(Target)) {
1908 // @public and @package ivars are always accessible.
1909 if (Ivar->getCanonicalAccessControl() == ObjCIvarDecl::Public ||
1910 Ivar->getCanonicalAccessControl() == ObjCIvarDecl::Package)
1911 return true;
1912
1913 // If we are inside a class or category implementation, determine the
1914 // interface we're in.
1915 ObjCInterfaceDecl *ClassOfMethodDecl = nullptr;
1916 if (ObjCMethodDecl *MD = getCurMethodDecl())
1917 ClassOfMethodDecl = MD->getClassInterface();
1918 else if (FunctionDecl *FD = getCurFunctionDecl()) {
1919 if (ObjCImplDecl *Impl
1920 = dyn_cast<ObjCImplDecl>(FD->getLexicalDeclContext())) {
1921 if (ObjCImplementationDecl *IMPD
1922 = dyn_cast<ObjCImplementationDecl>(Impl))
1923 ClassOfMethodDecl = IMPD->getClassInterface();
1924 else if (ObjCCategoryImplDecl* CatImplClass
1925 = dyn_cast<ObjCCategoryImplDecl>(Impl))
1926 ClassOfMethodDecl = CatImplClass->getClassInterface();
1927 }
1928 }
1929
1930 // If we're not in an interface, this ivar is inaccessible.
1931 if (!ClassOfMethodDecl)
1932 return false;
1933
1934 // If we're inside the same interface that owns the ivar, we're fine.
1935 if (declaresSameEntity(ClassOfMethodDecl, Ivar->getContainingInterface()))
1936 return true;
1937
1938 // If the ivar is private, it's inaccessible.
1939 if (Ivar->getCanonicalAccessControl() == ObjCIvarDecl::Private)
1940 return false;
1941
1942 return Ivar->getContainingInterface()->isSuperClassOf(ClassOfMethodDecl);
1943 }
1944
1945 return true;
1946}