1 //===--- SemaDeclObjC.cpp - Semantic Analysis for ObjC 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 Objective C declarations.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "TypeLocBuilder.h"
14 #include "clang/AST/ASTConsumer.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/ASTMutationListener.h"
17 #include "clang/AST/DeclObjC.h"
18 #include "clang/AST/Expr.h"
19 #include "clang/AST/ExprObjC.h"
20 #include "clang/AST/RecursiveASTVisitor.h"
21 #include "clang/Basic/SourceManager.h"
22 #include "clang/Basic/TargetInfo.h"
23 #include "clang/Sema/DeclSpec.h"
24 #include "clang/Sema/Lookup.h"
25 #include "clang/Sema/Scope.h"
26 #include "clang/Sema/ScopeInfo.h"
27 #include "clang/Sema/SemaInternal.h"
28 #include "llvm/ADT/DenseMap.h"
29 #include "llvm/ADT/DenseSet.h"
30
31 using namespace clang;
32
33 /// Check whether the given method, which must be in the 'init'
34 /// family, is a valid member of that family.
35 ///
36 /// \param receiverTypeIfCall - if null, check this as if declaring it;
37 /// if non-null, check this as if making a call to it with the given
38 /// receiver type
39 ///
40 /// \return true to indicate that there was an error and appropriate
41 /// actions were taken
checkInitMethod(ObjCMethodDecl * method,QualType receiverTypeIfCall)42 bool Sema::checkInitMethod(ObjCMethodDecl *method,
43 QualType receiverTypeIfCall) {
44 if (method->isInvalidDecl()) return true;
45
46 // This castAs is safe: methods that don't return an object
47 // pointer won't be inferred as inits and will reject an explicit
48 // objc_method_family(init).
49
50 // We ignore protocols here. Should we? What about Class?
51
52 const ObjCObjectType *result =
53 method->getReturnType()->castAs<ObjCObjectPointerType>()->getObjectType();
54
55 if (result->isObjCId()) {
56 return false;
57 } else if (result->isObjCClass()) {
58 // fall through: always an error
59 } else {
60 ObjCInterfaceDecl *resultClass = result->getInterface();
61 assert(resultClass && "unexpected object type!");
62
63 // It's okay for the result type to still be a forward declaration
64 // if we're checking an interface declaration.
65 if (!resultClass->hasDefinition()) {
66 if (receiverTypeIfCall.isNull() &&
67 !isa<ObjCImplementationDecl>(method->getDeclContext()))
68 return false;
69
70 // Otherwise, we try to compare class types.
71 } else {
72 // If this method was declared in a protocol, we can't check
73 // anything unless we have a receiver type that's an interface.
74 const ObjCInterfaceDecl *receiverClass = nullptr;
75 if (isa<ObjCProtocolDecl>(method->getDeclContext())) {
76 if (receiverTypeIfCall.isNull())
77 return false;
78
79 receiverClass = receiverTypeIfCall->castAs<ObjCObjectPointerType>()
80 ->getInterfaceDecl();
81
82 // This can be null for calls to e.g. id<Foo>.
83 if (!receiverClass) return false;
84 } else {
85 receiverClass = method->getClassInterface();
86 assert(receiverClass && "method not associated with a class!");
87 }
88
89 // If either class is a subclass of the other, it's fine.
90 if (receiverClass->isSuperClassOf(resultClass) ||
91 resultClass->isSuperClassOf(receiverClass))
92 return false;
93 }
94 }
95
96 SourceLocation loc = method->getLocation();
97
98 // If we're in a system header, and this is not a call, just make
99 // the method unusable.
100 if (receiverTypeIfCall.isNull() && getSourceManager().isInSystemHeader(loc)) {
101 method->addAttr(UnavailableAttr::CreateImplicit(Context, "",
102 UnavailableAttr::IR_ARCInitReturnsUnrelated, loc));
103 return true;
104 }
105
106 // Otherwise, it's an error.
107 Diag(loc, diag::err_arc_init_method_unrelated_result_type);
108 method->setInvalidDecl();
109 return true;
110 }
111
112 /// Issue a warning if the parameter of the overridden method is non-escaping
113 /// but the parameter of the overriding method is not.
diagnoseNoescape(const ParmVarDecl * NewD,const ParmVarDecl * OldD,Sema & S)114 static bool diagnoseNoescape(const ParmVarDecl *NewD, const ParmVarDecl *OldD,
115 Sema &S) {
116 if (OldD->hasAttr<NoEscapeAttr>() && !NewD->hasAttr<NoEscapeAttr>()) {
117 S.Diag(NewD->getLocation(), diag::warn_overriding_method_missing_noescape);
118 S.Diag(OldD->getLocation(), diag::note_overridden_marked_noescape);
119 return false;
120 }
121
122 return true;
123 }
124
125 /// Produce additional diagnostics if a category conforms to a protocol that
126 /// defines a method taking a non-escaping parameter.
diagnoseNoescape(const ParmVarDecl * NewD,const ParmVarDecl * OldD,const ObjCCategoryDecl * CD,const ObjCProtocolDecl * PD,Sema & S)127 static void diagnoseNoescape(const ParmVarDecl *NewD, const ParmVarDecl *OldD,
128 const ObjCCategoryDecl *CD,
129 const ObjCProtocolDecl *PD, Sema &S) {
130 if (!diagnoseNoescape(NewD, OldD, S))
131 S.Diag(CD->getLocation(), diag::note_cat_conform_to_noescape_prot)
132 << CD->IsClassExtension() << PD
133 << cast<ObjCMethodDecl>(NewD->getDeclContext());
134 }
135
CheckObjCMethodOverride(ObjCMethodDecl * NewMethod,const ObjCMethodDecl * Overridden)136 void Sema::CheckObjCMethodOverride(ObjCMethodDecl *NewMethod,
137 const ObjCMethodDecl *Overridden) {
138 if (Overridden->hasRelatedResultType() &&
139 !NewMethod->hasRelatedResultType()) {
140 // This can only happen when the method follows a naming convention that
141 // implies a related result type, and the original (overridden) method has
142 // a suitable return type, but the new (overriding) method does not have
143 // a suitable return type.
144 QualType ResultType = NewMethod->getReturnType();
145 SourceRange ResultTypeRange = NewMethod->getReturnTypeSourceRange();
146
147 // Figure out which class this method is part of, if any.
148 ObjCInterfaceDecl *CurrentClass
149 = dyn_cast<ObjCInterfaceDecl>(NewMethod->getDeclContext());
150 if (!CurrentClass) {
151 DeclContext *DC = NewMethod->getDeclContext();
152 if (ObjCCategoryDecl *Cat = dyn_cast<ObjCCategoryDecl>(DC))
153 CurrentClass = Cat->getClassInterface();
154 else if (ObjCImplDecl *Impl = dyn_cast<ObjCImplDecl>(DC))
155 CurrentClass = Impl->getClassInterface();
156 else if (ObjCCategoryImplDecl *CatImpl
157 = dyn_cast<ObjCCategoryImplDecl>(DC))
158 CurrentClass = CatImpl->getClassInterface();
159 }
160
161 if (CurrentClass) {
162 Diag(NewMethod->getLocation(),
163 diag::warn_related_result_type_compatibility_class)
164 << Context.getObjCInterfaceType(CurrentClass)
165 << ResultType
166 << ResultTypeRange;
167 } else {
168 Diag(NewMethod->getLocation(),
169 diag::warn_related_result_type_compatibility_protocol)
170 << ResultType
171 << ResultTypeRange;
172 }
173
174 if (ObjCMethodFamily Family = Overridden->getMethodFamily())
175 Diag(Overridden->getLocation(),
176 diag::note_related_result_type_family)
177 << /*overridden method*/ 0
178 << Family;
179 else
180 Diag(Overridden->getLocation(),
181 diag::note_related_result_type_overridden);
182 }
183
184 if ((NewMethod->hasAttr<NSReturnsRetainedAttr>() !=
185 Overridden->hasAttr<NSReturnsRetainedAttr>())) {
186 Diag(NewMethod->getLocation(),
187 getLangOpts().ObjCAutoRefCount
188 ? diag::err_nsreturns_retained_attribute_mismatch
189 : diag::warn_nsreturns_retained_attribute_mismatch)
190 << 1;
191 Diag(Overridden->getLocation(), diag::note_previous_decl) << "method";
192 }
193 if ((NewMethod->hasAttr<NSReturnsNotRetainedAttr>() !=
194 Overridden->hasAttr<NSReturnsNotRetainedAttr>())) {
195 Diag(NewMethod->getLocation(),
196 getLangOpts().ObjCAutoRefCount
197 ? diag::err_nsreturns_retained_attribute_mismatch
198 : diag::warn_nsreturns_retained_attribute_mismatch)
199 << 0;
200 Diag(Overridden->getLocation(), diag::note_previous_decl) << "method";
201 }
202
203 ObjCMethodDecl::param_const_iterator oi = Overridden->param_begin(),
204 oe = Overridden->param_end();
205 for (ObjCMethodDecl::param_iterator ni = NewMethod->param_begin(),
206 ne = NewMethod->param_end();
207 ni != ne && oi != oe; ++ni, ++oi) {
208 const ParmVarDecl *oldDecl = (*oi);
209 ParmVarDecl *newDecl = (*ni);
210 if (newDecl->hasAttr<NSConsumedAttr>() !=
211 oldDecl->hasAttr<NSConsumedAttr>()) {
212 Diag(newDecl->getLocation(),
213 getLangOpts().ObjCAutoRefCount
214 ? diag::err_nsconsumed_attribute_mismatch
215 : diag::warn_nsconsumed_attribute_mismatch);
216 Diag(oldDecl->getLocation(), diag::note_previous_decl) << "parameter";
217 }
218
219 diagnoseNoescape(newDecl, oldDecl, *this);
220 }
221 }
222
223 /// Check a method declaration for compatibility with the Objective-C
224 /// ARC conventions.
CheckARCMethodDecl(ObjCMethodDecl * method)225 bool Sema::CheckARCMethodDecl(ObjCMethodDecl *method) {
226 ObjCMethodFamily family = method->getMethodFamily();
227 switch (family) {
228 case OMF_None:
229 case OMF_finalize:
230 case OMF_retain:
231 case OMF_release:
232 case OMF_autorelease:
233 case OMF_retainCount:
234 case OMF_self:
235 case OMF_initialize:
236 case OMF_performSelector:
237 return false;
238
239 case OMF_dealloc:
240 if (!Context.hasSameType(method->getReturnType(), Context.VoidTy)) {
241 SourceRange ResultTypeRange = method->getReturnTypeSourceRange();
242 if (ResultTypeRange.isInvalid())
243 Diag(method->getLocation(), diag::err_dealloc_bad_result_type)
244 << method->getReturnType()
245 << FixItHint::CreateInsertion(method->getSelectorLoc(0), "(void)");
246 else
247 Diag(method->getLocation(), diag::err_dealloc_bad_result_type)
248 << method->getReturnType()
249 << FixItHint::CreateReplacement(ResultTypeRange, "void");
250 return true;
251 }
252 return false;
253
254 case OMF_init:
255 // If the method doesn't obey the init rules, don't bother annotating it.
256 if (checkInitMethod(method, QualType()))
257 return true;
258
259 method->addAttr(NSConsumesSelfAttr::CreateImplicit(Context));
260
261 // Don't add a second copy of this attribute, but otherwise don't
262 // let it be suppressed.
263 if (method->hasAttr<NSReturnsRetainedAttr>())
264 return false;
265 break;
266
267 case OMF_alloc:
268 case OMF_copy:
269 case OMF_mutableCopy:
270 case OMF_new:
271 if (method->hasAttr<NSReturnsRetainedAttr>() ||
272 method->hasAttr<NSReturnsNotRetainedAttr>() ||
273 method->hasAttr<NSReturnsAutoreleasedAttr>())
274 return false;
275 break;
276 }
277
278 method->addAttr(NSReturnsRetainedAttr::CreateImplicit(Context));
279 return false;
280 }
281
DiagnoseObjCImplementedDeprecations(Sema & S,const NamedDecl * ND,SourceLocation ImplLoc)282 static void DiagnoseObjCImplementedDeprecations(Sema &S, const NamedDecl *ND,
283 SourceLocation ImplLoc) {
284 if (!ND)
285 return;
286 bool IsCategory = false;
287 StringRef RealizedPlatform;
288 AvailabilityResult Availability = ND->getAvailability(
289 /*Message=*/nullptr, /*EnclosingVersion=*/VersionTuple(),
290 &RealizedPlatform);
291 if (Availability != AR_Deprecated) {
292 if (isa<ObjCMethodDecl>(ND)) {
293 if (Availability != AR_Unavailable)
294 return;
295 if (RealizedPlatform.empty())
296 RealizedPlatform = S.Context.getTargetInfo().getPlatformName();
297 // Warn about implementing unavailable methods, unless the unavailable
298 // is for an app extension.
299 if (RealizedPlatform.endswith("_app_extension"))
300 return;
301 S.Diag(ImplLoc, diag::warn_unavailable_def);
302 S.Diag(ND->getLocation(), diag::note_method_declared_at)
303 << ND->getDeclName();
304 return;
305 }
306 if (const auto *CD = dyn_cast<ObjCCategoryDecl>(ND)) {
307 if (!CD->getClassInterface()->isDeprecated())
308 return;
309 ND = CD->getClassInterface();
310 IsCategory = true;
311 } else
312 return;
313 }
314 S.Diag(ImplLoc, diag::warn_deprecated_def)
315 << (isa<ObjCMethodDecl>(ND)
316 ? /*Method*/ 0
317 : isa<ObjCCategoryDecl>(ND) || IsCategory ? /*Category*/ 2
318 : /*Class*/ 1);
319 if (isa<ObjCMethodDecl>(ND))
320 S.Diag(ND->getLocation(), diag::note_method_declared_at)
321 << ND->getDeclName();
322 else
323 S.Diag(ND->getLocation(), diag::note_previous_decl)
324 << (isa<ObjCCategoryDecl>(ND) ? "category" : "class");
325 }
326
327 /// AddAnyMethodToGlobalPool - Add any method, instance or factory to global
328 /// pool.
AddAnyMethodToGlobalPool(Decl * D)329 void Sema::AddAnyMethodToGlobalPool(Decl *D) {
330 ObjCMethodDecl *MDecl = dyn_cast_or_null<ObjCMethodDecl>(D);
331
332 // If we don't have a valid method decl, simply return.
333 if (!MDecl)
334 return;
335 if (MDecl->isInstanceMethod())
336 AddInstanceMethodToGlobalPool(MDecl, true);
337 else
338 AddFactoryMethodToGlobalPool(MDecl, true);
339 }
340
341 /// HasExplicitOwnershipAttr - returns true when pointer to ObjC pointer
342 /// has explicit ownership attribute; false otherwise.
343 static bool
HasExplicitOwnershipAttr(Sema & S,ParmVarDecl * Param)344 HasExplicitOwnershipAttr(Sema &S, ParmVarDecl *Param) {
345 QualType T = Param->getType();
346
347 if (const PointerType *PT = T->getAs<PointerType>()) {
348 T = PT->getPointeeType();
349 } else if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
350 T = RT->getPointeeType();
351 } else {
352 return true;
353 }
354
355 // If we have a lifetime qualifier, but it's local, we must have
356 // inferred it. So, it is implicit.
357 return !T.getLocalQualifiers().hasObjCLifetime();
358 }
359
360 /// ActOnStartOfObjCMethodDef - This routine sets up parameters; invisible
361 /// and user declared, in the method definition's AST.
ActOnStartOfObjCMethodDef(Scope * FnBodyScope,Decl * D)362 void Sema::ActOnStartOfObjCMethodDef(Scope *FnBodyScope, Decl *D) {
363 ImplicitlyRetainedSelfLocs.clear();
364 assert((getCurMethodDecl() == nullptr) && "Methodparsing confused");
365 ObjCMethodDecl *MDecl = dyn_cast_or_null<ObjCMethodDecl>(D);
366
367 PushExpressionEvaluationContext(ExprEvalContexts.back().Context);
368
369 // If we don't have a valid method decl, simply return.
370 if (!MDecl)
371 return;
372
373 QualType ResultType = MDecl->getReturnType();
374 if (!ResultType->isDependentType() && !ResultType->isVoidType() &&
375 !MDecl->isInvalidDecl() &&
376 RequireCompleteType(MDecl->getLocation(), ResultType,
377 diag::err_func_def_incomplete_result))
378 MDecl->setInvalidDecl();
379
380 // Allow all of Sema to see that we are entering a method definition.
381 PushDeclContext(FnBodyScope, MDecl);
382 PushFunctionScope();
383
384 // Create Decl objects for each parameter, entrring them in the scope for
385 // binding to their use.
386
387 // Insert the invisible arguments, self and _cmd!
388 MDecl->createImplicitParams(Context, MDecl->getClassInterface());
389
390 PushOnScopeChains(MDecl->getSelfDecl(), FnBodyScope);
391 PushOnScopeChains(MDecl->getCmdDecl(), FnBodyScope);
392
393 // The ObjC parser requires parameter names so there's no need to check.
394 CheckParmsForFunctionDef(MDecl->parameters(),
395 /*CheckParameterNames=*/false);
396
397 // Introduce all of the other parameters into this scope.
398 for (auto *Param : MDecl->parameters()) {
399 if (!Param->isInvalidDecl() &&
400 getLangOpts().ObjCAutoRefCount &&
401 !HasExplicitOwnershipAttr(*this, Param))
402 Diag(Param->getLocation(), diag::warn_arc_strong_pointer_objc_pointer) <<
403 Param->getType();
404
405 if (Param->getIdentifier())
406 PushOnScopeChains(Param, FnBodyScope);
407 }
408
409 // In ARC, disallow definition of retain/release/autorelease/retainCount
410 if (getLangOpts().ObjCAutoRefCount) {
411 switch (MDecl->getMethodFamily()) {
412 case OMF_retain:
413 case OMF_retainCount:
414 case OMF_release:
415 case OMF_autorelease:
416 Diag(MDecl->getLocation(), diag::err_arc_illegal_method_def)
417 << 0 << MDecl->getSelector();
418 break;
419
420 case OMF_None:
421 case OMF_dealloc:
422 case OMF_finalize:
423 case OMF_alloc:
424 case OMF_init:
425 case OMF_mutableCopy:
426 case OMF_copy:
427 case OMF_new:
428 case OMF_self:
429 case OMF_initialize:
430 case OMF_performSelector:
431 break;
432 }
433 }
434
435 // Warn on deprecated methods under -Wdeprecated-implementations,
436 // and prepare for warning on missing super calls.
437 if (ObjCInterfaceDecl *IC = MDecl->getClassInterface()) {
438 ObjCMethodDecl *IMD =
439 IC->lookupMethod(MDecl->getSelector(), MDecl->isInstanceMethod());
440
441 if (IMD) {
442 ObjCImplDecl *ImplDeclOfMethodDef =
443 dyn_cast<ObjCImplDecl>(MDecl->getDeclContext());
444 ObjCContainerDecl *ContDeclOfMethodDecl =
445 dyn_cast<ObjCContainerDecl>(IMD->getDeclContext());
446 ObjCImplDecl *ImplDeclOfMethodDecl = nullptr;
447 if (ObjCInterfaceDecl *OID = dyn_cast<ObjCInterfaceDecl>(ContDeclOfMethodDecl))
448 ImplDeclOfMethodDecl = OID->getImplementation();
449 else if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(ContDeclOfMethodDecl)) {
450 if (CD->IsClassExtension()) {
451 if (ObjCInterfaceDecl *OID = CD->getClassInterface())
452 ImplDeclOfMethodDecl = OID->getImplementation();
453 } else
454 ImplDeclOfMethodDecl = CD->getImplementation();
455 }
456 // No need to issue deprecated warning if deprecated mehod in class/category
457 // is being implemented in its own implementation (no overriding is involved).
458 if (!ImplDeclOfMethodDecl || ImplDeclOfMethodDecl != ImplDeclOfMethodDef)
459 DiagnoseObjCImplementedDeprecations(*this, IMD, MDecl->getLocation());
460 }
461
462 if (MDecl->getMethodFamily() == OMF_init) {
463 if (MDecl->isDesignatedInitializerForTheInterface()) {
464 getCurFunction()->ObjCIsDesignatedInit = true;
465 getCurFunction()->ObjCWarnForNoDesignatedInitChain =
466 IC->getSuperClass() != nullptr;
467 } else if (IC->hasDesignatedInitializers()) {
468 getCurFunction()->ObjCIsSecondaryInit = true;
469 getCurFunction()->ObjCWarnForNoInitDelegation = true;
470 }
471 }
472
473 // If this is "dealloc" or "finalize", set some bit here.
474 // Then in ActOnSuperMessage() (SemaExprObjC), set it back to false.
475 // Finally, in ActOnFinishFunctionBody() (SemaDecl), warn if flag is set.
476 // Only do this if the current class actually has a superclass.
477 if (const ObjCInterfaceDecl *SuperClass = IC->getSuperClass()) {
478 ObjCMethodFamily Family = MDecl->getMethodFamily();
479 if (Family == OMF_dealloc) {
480 if (!(getLangOpts().ObjCAutoRefCount ||
481 getLangOpts().getGC() == LangOptions::GCOnly))
482 getCurFunction()->ObjCShouldCallSuper = true;
483
484 } else if (Family == OMF_finalize) {
485 if (Context.getLangOpts().getGC() != LangOptions::NonGC)
486 getCurFunction()->ObjCShouldCallSuper = true;
487
488 } else {
489 const ObjCMethodDecl *SuperMethod =
490 SuperClass->lookupMethod(MDecl->getSelector(),
491 MDecl->isInstanceMethod());
492 getCurFunction()->ObjCShouldCallSuper =
493 (SuperMethod && SuperMethod->hasAttr<ObjCRequiresSuperAttr>());
494 }
495 }
496 }
497 }
498
499 namespace {
500
501 // Callback to only accept typo corrections that are Objective-C classes.
502 // If an ObjCInterfaceDecl* is given to the constructor, then the validation
503 // function will reject corrections to that class.
504 class ObjCInterfaceValidatorCCC final : public CorrectionCandidateCallback {
505 public:
ObjCInterfaceValidatorCCC()506 ObjCInterfaceValidatorCCC() : CurrentIDecl(nullptr) {}
ObjCInterfaceValidatorCCC(ObjCInterfaceDecl * IDecl)507 explicit ObjCInterfaceValidatorCCC(ObjCInterfaceDecl *IDecl)
508 : CurrentIDecl(IDecl) {}
509
ValidateCandidate(const TypoCorrection & candidate)510 bool ValidateCandidate(const TypoCorrection &candidate) override {
511 ObjCInterfaceDecl *ID = candidate.getCorrectionDeclAs<ObjCInterfaceDecl>();
512 return ID && !declaresSameEntity(ID, CurrentIDecl);
513 }
514
clone()515 std::unique_ptr<CorrectionCandidateCallback> clone() override {
516 return std::make_unique<ObjCInterfaceValidatorCCC>(*this);
517 }
518
519 private:
520 ObjCInterfaceDecl *CurrentIDecl;
521 };
522
523 } // end anonymous namespace
524
diagnoseUseOfProtocols(Sema & TheSema,ObjCContainerDecl * CD,ObjCProtocolDecl * const * ProtoRefs,unsigned NumProtoRefs,const SourceLocation * ProtoLocs)525 static void diagnoseUseOfProtocols(Sema &TheSema,
526 ObjCContainerDecl *CD,
527 ObjCProtocolDecl *const *ProtoRefs,
528 unsigned NumProtoRefs,
529 const SourceLocation *ProtoLocs) {
530 assert(ProtoRefs);
531 // Diagnose availability in the context of the ObjC container.
532 Sema::ContextRAII SavedContext(TheSema, CD);
533 for (unsigned i = 0; i < NumProtoRefs; ++i) {
534 (void)TheSema.DiagnoseUseOfDecl(ProtoRefs[i], ProtoLocs[i],
535 /*UnknownObjCClass=*/nullptr,
536 /*ObjCPropertyAccess=*/false,
537 /*AvoidPartialAvailabilityChecks=*/true);
538 }
539 }
540
541 void Sema::
ActOnSuperClassOfClassInterface(Scope * S,SourceLocation AtInterfaceLoc,ObjCInterfaceDecl * IDecl,IdentifierInfo * ClassName,SourceLocation ClassLoc,IdentifierInfo * SuperName,SourceLocation SuperLoc,ArrayRef<ParsedType> SuperTypeArgs,SourceRange SuperTypeArgsRange)542 ActOnSuperClassOfClassInterface(Scope *S,
543 SourceLocation AtInterfaceLoc,
544 ObjCInterfaceDecl *IDecl,
545 IdentifierInfo *ClassName,
546 SourceLocation ClassLoc,
547 IdentifierInfo *SuperName,
548 SourceLocation SuperLoc,
549 ArrayRef<ParsedType> SuperTypeArgs,
550 SourceRange SuperTypeArgsRange) {
551 // Check if a different kind of symbol declared in this scope.
552 NamedDecl *PrevDecl = LookupSingleName(TUScope, SuperName, SuperLoc,
553 LookupOrdinaryName);
554
555 if (!PrevDecl) {
556 // Try to correct for a typo in the superclass name without correcting
557 // to the class we're defining.
558 ObjCInterfaceValidatorCCC CCC(IDecl);
559 if (TypoCorrection Corrected = CorrectTypo(
560 DeclarationNameInfo(SuperName, SuperLoc), LookupOrdinaryName,
561 TUScope, nullptr, CCC, CTK_ErrorRecovery)) {
562 diagnoseTypo(Corrected, PDiag(diag::err_undef_superclass_suggest)
563 << SuperName << ClassName);
564 PrevDecl = Corrected.getCorrectionDeclAs<ObjCInterfaceDecl>();
565 }
566 }
567
568 if (declaresSameEntity(PrevDecl, IDecl)) {
569 Diag(SuperLoc, diag::err_recursive_superclass)
570 << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
571 IDecl->setEndOfDefinitionLoc(ClassLoc);
572 } else {
573 ObjCInterfaceDecl *SuperClassDecl =
574 dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
575 QualType SuperClassType;
576
577 // Diagnose classes that inherit from deprecated classes.
578 if (SuperClassDecl) {
579 (void)DiagnoseUseOfDecl(SuperClassDecl, SuperLoc);
580 SuperClassType = Context.getObjCInterfaceType(SuperClassDecl);
581 }
582
583 if (PrevDecl && !SuperClassDecl) {
584 // The previous declaration was not a class decl. Check if we have a
585 // typedef. If we do, get the underlying class type.
586 if (const TypedefNameDecl *TDecl =
587 dyn_cast_or_null<TypedefNameDecl>(PrevDecl)) {
588 QualType T = TDecl->getUnderlyingType();
589 if (T->isObjCObjectType()) {
590 if (NamedDecl *IDecl = T->castAs<ObjCObjectType>()->getInterface()) {
591 SuperClassDecl = dyn_cast<ObjCInterfaceDecl>(IDecl);
592 SuperClassType = Context.getTypeDeclType(TDecl);
593
594 // This handles the following case:
595 // @interface NewI @end
596 // typedef NewI DeprI __attribute__((deprecated("blah")))
597 // @interface SI : DeprI /* warn here */ @end
598 (void)DiagnoseUseOfDecl(const_cast<TypedefNameDecl*>(TDecl), SuperLoc);
599 }
600 }
601 }
602
603 // This handles the following case:
604 //
605 // typedef int SuperClass;
606 // @interface MyClass : SuperClass {} @end
607 //
608 if (!SuperClassDecl) {
609 Diag(SuperLoc, diag::err_redefinition_different_kind) << SuperName;
610 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
611 }
612 }
613
614 if (!dyn_cast_or_null<TypedefNameDecl>(PrevDecl)) {
615 if (!SuperClassDecl)
616 Diag(SuperLoc, diag::err_undef_superclass)
617 << SuperName << ClassName << SourceRange(AtInterfaceLoc, ClassLoc);
618 else if (RequireCompleteType(SuperLoc,
619 SuperClassType,
620 diag::err_forward_superclass,
621 SuperClassDecl->getDeclName(),
622 ClassName,
623 SourceRange(AtInterfaceLoc, ClassLoc))) {
624 SuperClassDecl = nullptr;
625 SuperClassType = QualType();
626 }
627 }
628
629 if (SuperClassType.isNull()) {
630 assert(!SuperClassDecl && "Failed to set SuperClassType?");
631 return;
632 }
633
634 // Handle type arguments on the superclass.
635 TypeSourceInfo *SuperClassTInfo = nullptr;
636 if (!SuperTypeArgs.empty()) {
637 TypeResult fullSuperClassType = actOnObjCTypeArgsAndProtocolQualifiers(
638 S,
639 SuperLoc,
640 CreateParsedType(SuperClassType,
641 nullptr),
642 SuperTypeArgsRange.getBegin(),
643 SuperTypeArgs,
644 SuperTypeArgsRange.getEnd(),
645 SourceLocation(),
646 { },
647 { },
648 SourceLocation());
649 if (!fullSuperClassType.isUsable())
650 return;
651
652 SuperClassType = GetTypeFromParser(fullSuperClassType.get(),
653 &SuperClassTInfo);
654 }
655
656 if (!SuperClassTInfo) {
657 SuperClassTInfo = Context.getTrivialTypeSourceInfo(SuperClassType,
658 SuperLoc);
659 }
660
661 IDecl->setSuperClass(SuperClassTInfo);
662 IDecl->setEndOfDefinitionLoc(SuperClassTInfo->getTypeLoc().getEndLoc());
663 }
664 }
665
actOnObjCTypeParam(Scope * S,ObjCTypeParamVariance variance,SourceLocation varianceLoc,unsigned index,IdentifierInfo * paramName,SourceLocation paramLoc,SourceLocation colonLoc,ParsedType parsedTypeBound)666 DeclResult Sema::actOnObjCTypeParam(Scope *S,
667 ObjCTypeParamVariance variance,
668 SourceLocation varianceLoc,
669 unsigned index,
670 IdentifierInfo *paramName,
671 SourceLocation paramLoc,
672 SourceLocation colonLoc,
673 ParsedType parsedTypeBound) {
674 // If there was an explicitly-provided type bound, check it.
675 TypeSourceInfo *typeBoundInfo = nullptr;
676 if (parsedTypeBound) {
677 // The type bound can be any Objective-C pointer type.
678 QualType typeBound = GetTypeFromParser(parsedTypeBound, &typeBoundInfo);
679 if (typeBound->isObjCObjectPointerType()) {
680 // okay
681 } else if (typeBound->isObjCObjectType()) {
682 // The user forgot the * on an Objective-C pointer type, e.g.,
683 // "T : NSView".
684 SourceLocation starLoc = getLocForEndOfToken(
685 typeBoundInfo->getTypeLoc().getEndLoc());
686 Diag(typeBoundInfo->getTypeLoc().getBeginLoc(),
687 diag::err_objc_type_param_bound_missing_pointer)
688 << typeBound << paramName
689 << FixItHint::CreateInsertion(starLoc, " *");
690
691 // Create a new type location builder so we can update the type
692 // location information we have.
693 TypeLocBuilder builder;
694 builder.pushFullCopy(typeBoundInfo->getTypeLoc());
695
696 // Create the Objective-C pointer type.
697 typeBound = Context.getObjCObjectPointerType(typeBound);
698 ObjCObjectPointerTypeLoc newT
699 = builder.push<ObjCObjectPointerTypeLoc>(typeBound);
700 newT.setStarLoc(starLoc);
701
702 // Form the new type source information.
703 typeBoundInfo = builder.getTypeSourceInfo(Context, typeBound);
704 } else {
705 // Not a valid type bound.
706 Diag(typeBoundInfo->getTypeLoc().getBeginLoc(),
707 diag::err_objc_type_param_bound_nonobject)
708 << typeBound << paramName;
709
710 // Forget the bound; we'll default to id later.
711 typeBoundInfo = nullptr;
712 }
713
714 // Type bounds cannot have qualifiers (even indirectly) or explicit
715 // nullability.
716 if (typeBoundInfo) {
717 QualType typeBound = typeBoundInfo->getType();
718 TypeLoc qual = typeBoundInfo->getTypeLoc().findExplicitQualifierLoc();
719 if (qual || typeBound.hasQualifiers()) {
720 bool diagnosed = false;
721 SourceRange rangeToRemove;
722 if (qual) {
723 if (auto attr = qual.getAs<AttributedTypeLoc>()) {
724 rangeToRemove = attr.getLocalSourceRange();
725 if (attr.getTypePtr()->getImmediateNullability()) {
726 Diag(attr.getBeginLoc(),
727 diag::err_objc_type_param_bound_explicit_nullability)
728 << paramName << typeBound
729 << FixItHint::CreateRemoval(rangeToRemove);
730 diagnosed = true;
731 }
732 }
733 }
734
735 if (!diagnosed) {
736 Diag(qual ? qual.getBeginLoc()
737 : typeBoundInfo->getTypeLoc().getBeginLoc(),
738 diag::err_objc_type_param_bound_qualified)
739 << paramName << typeBound
740 << typeBound.getQualifiers().getAsString()
741 << FixItHint::CreateRemoval(rangeToRemove);
742 }
743
744 // If the type bound has qualifiers other than CVR, we need to strip
745 // them or we'll probably assert later when trying to apply new
746 // qualifiers.
747 Qualifiers quals = typeBound.getQualifiers();
748 quals.removeCVRQualifiers();
749 if (!quals.empty()) {
750 typeBoundInfo =
751 Context.getTrivialTypeSourceInfo(typeBound.getUnqualifiedType());
752 }
753 }
754 }
755 }
756
757 // If there was no explicit type bound (or we removed it due to an error),
758 // use 'id' instead.
759 if (!typeBoundInfo) {
760 colonLoc = SourceLocation();
761 typeBoundInfo = Context.getTrivialTypeSourceInfo(Context.getObjCIdType());
762 }
763
764 // Create the type parameter.
765 return ObjCTypeParamDecl::Create(Context, CurContext, variance, varianceLoc,
766 index, paramLoc, paramName, colonLoc,
767 typeBoundInfo);
768 }
769
actOnObjCTypeParamList(Scope * S,SourceLocation lAngleLoc,ArrayRef<Decl * > typeParamsIn,SourceLocation rAngleLoc)770 ObjCTypeParamList *Sema::actOnObjCTypeParamList(Scope *S,
771 SourceLocation lAngleLoc,
772 ArrayRef<Decl *> typeParamsIn,
773 SourceLocation rAngleLoc) {
774 // We know that the array only contains Objective-C type parameters.
775 ArrayRef<ObjCTypeParamDecl *>
776 typeParams(
777 reinterpret_cast<ObjCTypeParamDecl * const *>(typeParamsIn.data()),
778 typeParamsIn.size());
779
780 // Diagnose redeclarations of type parameters.
781 // We do this now because Objective-C type parameters aren't pushed into
782 // scope until later (after the instance variable block), but we want the
783 // diagnostics to occur right after we parse the type parameter list.
784 llvm::SmallDenseMap<IdentifierInfo *, ObjCTypeParamDecl *> knownParams;
785 for (auto typeParam : typeParams) {
786 auto known = knownParams.find(typeParam->getIdentifier());
787 if (known != knownParams.end()) {
788 Diag(typeParam->getLocation(), diag::err_objc_type_param_redecl)
789 << typeParam->getIdentifier()
790 << SourceRange(known->second->getLocation());
791
792 typeParam->setInvalidDecl();
793 } else {
794 knownParams.insert(std::make_pair(typeParam->getIdentifier(), typeParam));
795
796 // Push the type parameter into scope.
797 PushOnScopeChains(typeParam, S, /*AddToContext=*/false);
798 }
799 }
800
801 // Create the parameter list.
802 return ObjCTypeParamList::create(Context, lAngleLoc, typeParams, rAngleLoc);
803 }
804
popObjCTypeParamList(Scope * S,ObjCTypeParamList * typeParamList)805 void Sema::popObjCTypeParamList(Scope *S, ObjCTypeParamList *typeParamList) {
806 for (auto typeParam : *typeParamList) {
807 if (!typeParam->isInvalidDecl()) {
808 S->RemoveDecl(typeParam);
809 IdResolver.RemoveDecl(typeParam);
810 }
811 }
812 }
813
814 namespace {
815 /// The context in which an Objective-C type parameter list occurs, for use
816 /// in diagnostics.
817 enum class TypeParamListContext {
818 ForwardDeclaration,
819 Definition,
820 Category,
821 Extension
822 };
823 } // end anonymous namespace
824
825 /// Check consistency between two Objective-C type parameter lists, e.g.,
826 /// between a category/extension and an \@interface or between an \@class and an
827 /// \@interface.
checkTypeParamListConsistency(Sema & S,ObjCTypeParamList * prevTypeParams,ObjCTypeParamList * newTypeParams,TypeParamListContext newContext)828 static bool checkTypeParamListConsistency(Sema &S,
829 ObjCTypeParamList *prevTypeParams,
830 ObjCTypeParamList *newTypeParams,
831 TypeParamListContext newContext) {
832 // If the sizes don't match, complain about that.
833 if (prevTypeParams->size() != newTypeParams->size()) {
834 SourceLocation diagLoc;
835 if (newTypeParams->size() > prevTypeParams->size()) {
836 diagLoc = newTypeParams->begin()[prevTypeParams->size()]->getLocation();
837 } else {
838 diagLoc = S.getLocForEndOfToken(newTypeParams->back()->getEndLoc());
839 }
840
841 S.Diag(diagLoc, diag::err_objc_type_param_arity_mismatch)
842 << static_cast<unsigned>(newContext)
843 << (newTypeParams->size() > prevTypeParams->size())
844 << prevTypeParams->size()
845 << newTypeParams->size();
846
847 return true;
848 }
849
850 // Match up the type parameters.
851 for (unsigned i = 0, n = prevTypeParams->size(); i != n; ++i) {
852 ObjCTypeParamDecl *prevTypeParam = prevTypeParams->begin()[i];
853 ObjCTypeParamDecl *newTypeParam = newTypeParams->begin()[i];
854
855 // Check for consistency of the variance.
856 if (newTypeParam->getVariance() != prevTypeParam->getVariance()) {
857 if (newTypeParam->getVariance() == ObjCTypeParamVariance::Invariant &&
858 newContext != TypeParamListContext::Definition) {
859 // When the new type parameter is invariant and is not part
860 // of the definition, just propagate the variance.
861 newTypeParam->setVariance(prevTypeParam->getVariance());
862 } else if (prevTypeParam->getVariance()
863 == ObjCTypeParamVariance::Invariant &&
864 !(isa<ObjCInterfaceDecl>(prevTypeParam->getDeclContext()) &&
865 cast<ObjCInterfaceDecl>(prevTypeParam->getDeclContext())
866 ->getDefinition() == prevTypeParam->getDeclContext())) {
867 // When the old parameter is invariant and was not part of the
868 // definition, just ignore the difference because it doesn't
869 // matter.
870 } else {
871 {
872 // Diagnose the conflict and update the second declaration.
873 SourceLocation diagLoc = newTypeParam->getVarianceLoc();
874 if (diagLoc.isInvalid())
875 diagLoc = newTypeParam->getBeginLoc();
876
877 auto diag = S.Diag(diagLoc,
878 diag::err_objc_type_param_variance_conflict)
879 << static_cast<unsigned>(newTypeParam->getVariance())
880 << newTypeParam->getDeclName()
881 << static_cast<unsigned>(prevTypeParam->getVariance())
882 << prevTypeParam->getDeclName();
883 switch (prevTypeParam->getVariance()) {
884 case ObjCTypeParamVariance::Invariant:
885 diag << FixItHint::CreateRemoval(newTypeParam->getVarianceLoc());
886 break;
887
888 case ObjCTypeParamVariance::Covariant:
889 case ObjCTypeParamVariance::Contravariant: {
890 StringRef newVarianceStr
891 = prevTypeParam->getVariance() == ObjCTypeParamVariance::Covariant
892 ? "__covariant"
893 : "__contravariant";
894 if (newTypeParam->getVariance()
895 == ObjCTypeParamVariance::Invariant) {
896 diag << FixItHint::CreateInsertion(newTypeParam->getBeginLoc(),
897 (newVarianceStr + " ").str());
898 } else {
899 diag << FixItHint::CreateReplacement(newTypeParam->getVarianceLoc(),
900 newVarianceStr);
901 }
902 }
903 }
904 }
905
906 S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
907 << prevTypeParam->getDeclName();
908
909 // Override the variance.
910 newTypeParam->setVariance(prevTypeParam->getVariance());
911 }
912 }
913
914 // If the bound types match, there's nothing to do.
915 if (S.Context.hasSameType(prevTypeParam->getUnderlyingType(),
916 newTypeParam->getUnderlyingType()))
917 continue;
918
919 // If the new type parameter's bound was explicit, complain about it being
920 // different from the original.
921 if (newTypeParam->hasExplicitBound()) {
922 SourceRange newBoundRange = newTypeParam->getTypeSourceInfo()
923 ->getTypeLoc().getSourceRange();
924 S.Diag(newBoundRange.getBegin(), diag::err_objc_type_param_bound_conflict)
925 << newTypeParam->getUnderlyingType()
926 << newTypeParam->getDeclName()
927 << prevTypeParam->hasExplicitBound()
928 << prevTypeParam->getUnderlyingType()
929 << (newTypeParam->getDeclName() == prevTypeParam->getDeclName())
930 << prevTypeParam->getDeclName()
931 << FixItHint::CreateReplacement(
932 newBoundRange,
933 prevTypeParam->getUnderlyingType().getAsString(
934 S.Context.getPrintingPolicy()));
935
936 S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
937 << prevTypeParam->getDeclName();
938
939 // Override the new type parameter's bound type with the previous type,
940 // so that it's consistent.
941 S.Context.adjustObjCTypeParamBoundType(prevTypeParam, newTypeParam);
942 continue;
943 }
944
945 // The new type parameter got the implicit bound of 'id'. That's okay for
946 // categories and extensions (overwrite it later), but not for forward
947 // declarations and @interfaces, because those must be standalone.
948 if (newContext == TypeParamListContext::ForwardDeclaration ||
949 newContext == TypeParamListContext::Definition) {
950 // Diagnose this problem for forward declarations and definitions.
951 SourceLocation insertionLoc
952 = S.getLocForEndOfToken(newTypeParam->getLocation());
953 std::string newCode
954 = " : " + prevTypeParam->getUnderlyingType().getAsString(
955 S.Context.getPrintingPolicy());
956 S.Diag(newTypeParam->getLocation(),
957 diag::err_objc_type_param_bound_missing)
958 << prevTypeParam->getUnderlyingType()
959 << newTypeParam->getDeclName()
960 << (newContext == TypeParamListContext::ForwardDeclaration)
961 << FixItHint::CreateInsertion(insertionLoc, newCode);
962
963 S.Diag(prevTypeParam->getLocation(), diag::note_objc_type_param_here)
964 << prevTypeParam->getDeclName();
965 }
966
967 // Update the new type parameter's bound to match the previous one.
968 S.Context.adjustObjCTypeParamBoundType(prevTypeParam, newTypeParam);
969 }
970
971 return false;
972 }
973
ActOnStartClassInterface(Scope * S,SourceLocation AtInterfaceLoc,IdentifierInfo * ClassName,SourceLocation ClassLoc,ObjCTypeParamList * typeParamList,IdentifierInfo * SuperName,SourceLocation SuperLoc,ArrayRef<ParsedType> SuperTypeArgs,SourceRange SuperTypeArgsRange,Decl * const * ProtoRefs,unsigned NumProtoRefs,const SourceLocation * ProtoLocs,SourceLocation EndProtoLoc,const ParsedAttributesView & AttrList)974 Decl *Sema::ActOnStartClassInterface(
975 Scope *S, SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName,
976 SourceLocation ClassLoc, ObjCTypeParamList *typeParamList,
977 IdentifierInfo *SuperName, SourceLocation SuperLoc,
978 ArrayRef<ParsedType> SuperTypeArgs, SourceRange SuperTypeArgsRange,
979 Decl *const *ProtoRefs, unsigned NumProtoRefs,
980 const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc,
981 const ParsedAttributesView &AttrList) {
982 assert(ClassName && "Missing class identifier");
983
984 // Check for another declaration kind with the same name.
985 NamedDecl *PrevDecl =
986 LookupSingleName(TUScope, ClassName, ClassLoc, LookupOrdinaryName,
987 forRedeclarationInCurContext());
988
989 if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
990 Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName;
991 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
992 }
993
994 // Create a declaration to describe this @interface.
995 ObjCInterfaceDecl* PrevIDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
996
997 if (PrevIDecl && PrevIDecl->getIdentifier() != ClassName) {
998 // A previous decl with a different name is because of
999 // @compatibility_alias, for example:
1000 // \code
1001 // @class NewImage;
1002 // @compatibility_alias OldImage NewImage;
1003 // \endcode
1004 // A lookup for 'OldImage' will return the 'NewImage' decl.
1005 //
1006 // In such a case use the real declaration name, instead of the alias one,
1007 // otherwise we will break IdentifierResolver and redecls-chain invariants.
1008 // FIXME: If necessary, add a bit to indicate that this ObjCInterfaceDecl
1009 // has been aliased.
1010 ClassName = PrevIDecl->getIdentifier();
1011 }
1012
1013 // If there was a forward declaration with type parameters, check
1014 // for consistency.
1015 if (PrevIDecl) {
1016 if (ObjCTypeParamList *prevTypeParamList = PrevIDecl->getTypeParamList()) {
1017 if (typeParamList) {
1018 // Both have type parameter lists; check for consistency.
1019 if (checkTypeParamListConsistency(*this, prevTypeParamList,
1020 typeParamList,
1021 TypeParamListContext::Definition)) {
1022 typeParamList = nullptr;
1023 }
1024 } else {
1025 Diag(ClassLoc, diag::err_objc_parameterized_forward_class_first)
1026 << ClassName;
1027 Diag(prevTypeParamList->getLAngleLoc(), diag::note_previous_decl)
1028 << ClassName;
1029
1030 // Clone the type parameter list.
1031 SmallVector<ObjCTypeParamDecl *, 4> clonedTypeParams;
1032 for (auto typeParam : *prevTypeParamList) {
1033 clonedTypeParams.push_back(
1034 ObjCTypeParamDecl::Create(
1035 Context,
1036 CurContext,
1037 typeParam->getVariance(),
1038 SourceLocation(),
1039 typeParam->getIndex(),
1040 SourceLocation(),
1041 typeParam->getIdentifier(),
1042 SourceLocation(),
1043 Context.getTrivialTypeSourceInfo(typeParam->getUnderlyingType())));
1044 }
1045
1046 typeParamList = ObjCTypeParamList::create(Context,
1047 SourceLocation(),
1048 clonedTypeParams,
1049 SourceLocation());
1050 }
1051 }
1052 }
1053
1054 ObjCInterfaceDecl *IDecl
1055 = ObjCInterfaceDecl::Create(Context, CurContext, AtInterfaceLoc, ClassName,
1056 typeParamList, PrevIDecl, ClassLoc);
1057 if (PrevIDecl) {
1058 // Class already seen. Was it a definition?
1059 if (ObjCInterfaceDecl *Def = PrevIDecl->getDefinition()) {
1060 Diag(AtInterfaceLoc, diag::err_duplicate_class_def)
1061 << PrevIDecl->getDeclName();
1062 Diag(Def->getLocation(), diag::note_previous_definition);
1063 IDecl->setInvalidDecl();
1064 }
1065 }
1066
1067 ProcessDeclAttributeList(TUScope, IDecl, AttrList);
1068 AddPragmaAttributes(TUScope, IDecl);
1069 PushOnScopeChains(IDecl, TUScope);
1070
1071 // Start the definition of this class. If we're in a redefinition case, there
1072 // may already be a definition, so we'll end up adding to it.
1073 if (!IDecl->hasDefinition())
1074 IDecl->startDefinition();
1075
1076 if (SuperName) {
1077 // Diagnose availability in the context of the @interface.
1078 ContextRAII SavedContext(*this, IDecl);
1079
1080 ActOnSuperClassOfClassInterface(S, AtInterfaceLoc, IDecl,
1081 ClassName, ClassLoc,
1082 SuperName, SuperLoc, SuperTypeArgs,
1083 SuperTypeArgsRange);
1084 } else { // we have a root class.
1085 IDecl->setEndOfDefinitionLoc(ClassLoc);
1086 }
1087
1088 // Check then save referenced protocols.
1089 if (NumProtoRefs) {
1090 diagnoseUseOfProtocols(*this, IDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1091 NumProtoRefs, ProtoLocs);
1092 IDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1093 ProtoLocs, Context);
1094 IDecl->setEndOfDefinitionLoc(EndProtoLoc);
1095 }
1096
1097 CheckObjCDeclScope(IDecl);
1098 return ActOnObjCContainerStartDefinition(IDecl);
1099 }
1100
1101 /// ActOnTypedefedProtocols - this action finds protocol list as part of the
1102 /// typedef'ed use for a qualified super class and adds them to the list
1103 /// of the protocols.
ActOnTypedefedProtocols(SmallVectorImpl<Decl * > & ProtocolRefs,SmallVectorImpl<SourceLocation> & ProtocolLocs,IdentifierInfo * SuperName,SourceLocation SuperLoc)1104 void Sema::ActOnTypedefedProtocols(SmallVectorImpl<Decl *> &ProtocolRefs,
1105 SmallVectorImpl<SourceLocation> &ProtocolLocs,
1106 IdentifierInfo *SuperName,
1107 SourceLocation SuperLoc) {
1108 if (!SuperName)
1109 return;
1110 NamedDecl* IDecl = LookupSingleName(TUScope, SuperName, SuperLoc,
1111 LookupOrdinaryName);
1112 if (!IDecl)
1113 return;
1114
1115 if (const TypedefNameDecl *TDecl = dyn_cast_or_null<TypedefNameDecl>(IDecl)) {
1116 QualType T = TDecl->getUnderlyingType();
1117 if (T->isObjCObjectType())
1118 if (const ObjCObjectType *OPT = T->getAs<ObjCObjectType>()) {
1119 ProtocolRefs.append(OPT->qual_begin(), OPT->qual_end());
1120 // FIXME: Consider whether this should be an invalid loc since the loc
1121 // is not actually pointing to a protocol name reference but to the
1122 // typedef reference. Note that the base class name loc is also pointing
1123 // at the typedef.
1124 ProtocolLocs.append(OPT->getNumProtocols(), SuperLoc);
1125 }
1126 }
1127 }
1128
1129 /// ActOnCompatibilityAlias - this action is called after complete parsing of
1130 /// a \@compatibility_alias declaration. It sets up the alias relationships.
ActOnCompatibilityAlias(SourceLocation AtLoc,IdentifierInfo * AliasName,SourceLocation AliasLocation,IdentifierInfo * ClassName,SourceLocation ClassLocation)1131 Decl *Sema::ActOnCompatibilityAlias(SourceLocation AtLoc,
1132 IdentifierInfo *AliasName,
1133 SourceLocation AliasLocation,
1134 IdentifierInfo *ClassName,
1135 SourceLocation ClassLocation) {
1136 // Look for previous declaration of alias name
1137 NamedDecl *ADecl =
1138 LookupSingleName(TUScope, AliasName, AliasLocation, LookupOrdinaryName,
1139 forRedeclarationInCurContext());
1140 if (ADecl) {
1141 Diag(AliasLocation, diag::err_conflicting_aliasing_type) << AliasName;
1142 Diag(ADecl->getLocation(), diag::note_previous_declaration);
1143 return nullptr;
1144 }
1145 // Check for class declaration
1146 NamedDecl *CDeclU =
1147 LookupSingleName(TUScope, ClassName, ClassLocation, LookupOrdinaryName,
1148 forRedeclarationInCurContext());
1149 if (const TypedefNameDecl *TDecl =
1150 dyn_cast_or_null<TypedefNameDecl>(CDeclU)) {
1151 QualType T = TDecl->getUnderlyingType();
1152 if (T->isObjCObjectType()) {
1153 if (NamedDecl *IDecl = T->castAs<ObjCObjectType>()->getInterface()) {
1154 ClassName = IDecl->getIdentifier();
1155 CDeclU = LookupSingleName(TUScope, ClassName, ClassLocation,
1156 LookupOrdinaryName,
1157 forRedeclarationInCurContext());
1158 }
1159 }
1160 }
1161 ObjCInterfaceDecl *CDecl = dyn_cast_or_null<ObjCInterfaceDecl>(CDeclU);
1162 if (!CDecl) {
1163 Diag(ClassLocation, diag::warn_undef_interface) << ClassName;
1164 if (CDeclU)
1165 Diag(CDeclU->getLocation(), diag::note_previous_declaration);
1166 return nullptr;
1167 }
1168
1169 // Everything checked out, instantiate a new alias declaration AST.
1170 ObjCCompatibleAliasDecl *AliasDecl =
1171 ObjCCompatibleAliasDecl::Create(Context, CurContext, AtLoc, AliasName, CDecl);
1172
1173 if (!CheckObjCDeclScope(AliasDecl))
1174 PushOnScopeChains(AliasDecl, TUScope);
1175
1176 return AliasDecl;
1177 }
1178
CheckForwardProtocolDeclarationForCircularDependency(IdentifierInfo * PName,SourceLocation & Ploc,SourceLocation PrevLoc,const ObjCList<ObjCProtocolDecl> & PList)1179 bool Sema::CheckForwardProtocolDeclarationForCircularDependency(
1180 IdentifierInfo *PName,
1181 SourceLocation &Ploc, SourceLocation PrevLoc,
1182 const ObjCList<ObjCProtocolDecl> &PList) {
1183
1184 bool res = false;
1185 for (ObjCList<ObjCProtocolDecl>::iterator I = PList.begin(),
1186 E = PList.end(); I != E; ++I) {
1187 if (ObjCProtocolDecl *PDecl = LookupProtocol((*I)->getIdentifier(),
1188 Ploc)) {
1189 if (PDecl->getIdentifier() == PName) {
1190 Diag(Ploc, diag::err_protocol_has_circular_dependency);
1191 Diag(PrevLoc, diag::note_previous_definition);
1192 res = true;
1193 }
1194
1195 if (!PDecl->hasDefinition())
1196 continue;
1197
1198 if (CheckForwardProtocolDeclarationForCircularDependency(PName, Ploc,
1199 PDecl->getLocation(), PDecl->getReferencedProtocols()))
1200 res = true;
1201 }
1202 }
1203 return res;
1204 }
1205
ActOnStartProtocolInterface(SourceLocation AtProtoInterfaceLoc,IdentifierInfo * ProtocolName,SourceLocation ProtocolLoc,Decl * const * ProtoRefs,unsigned NumProtoRefs,const SourceLocation * ProtoLocs,SourceLocation EndProtoLoc,const ParsedAttributesView & AttrList)1206 Decl *Sema::ActOnStartProtocolInterface(
1207 SourceLocation AtProtoInterfaceLoc, IdentifierInfo *ProtocolName,
1208 SourceLocation ProtocolLoc, Decl *const *ProtoRefs, unsigned NumProtoRefs,
1209 const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc,
1210 const ParsedAttributesView &AttrList) {
1211 bool err = false;
1212 // FIXME: Deal with AttrList.
1213 assert(ProtocolName && "Missing protocol identifier");
1214 ObjCProtocolDecl *PrevDecl = LookupProtocol(ProtocolName, ProtocolLoc,
1215 forRedeclarationInCurContext());
1216 ObjCProtocolDecl *PDecl = nullptr;
1217 if (ObjCProtocolDecl *Def = PrevDecl? PrevDecl->getDefinition() : nullptr) {
1218 // If we already have a definition, complain.
1219 Diag(ProtocolLoc, diag::warn_duplicate_protocol_def) << ProtocolName;
1220 Diag(Def->getLocation(), diag::note_previous_definition);
1221
1222 // Create a new protocol that is completely distinct from previous
1223 // declarations, and do not make this protocol available for name lookup.
1224 // That way, we'll end up completely ignoring the duplicate.
1225 // FIXME: Can we turn this into an error?
1226 PDecl = ObjCProtocolDecl::Create(Context, CurContext, ProtocolName,
1227 ProtocolLoc, AtProtoInterfaceLoc,
1228 /*PrevDecl=*/nullptr);
1229
1230 // If we are using modules, add the decl to the context in order to
1231 // serialize something meaningful.
1232 if (getLangOpts().Modules)
1233 PushOnScopeChains(PDecl, TUScope);
1234 PDecl->startDefinition();
1235 } else {
1236 if (PrevDecl) {
1237 // Check for circular dependencies among protocol declarations. This can
1238 // only happen if this protocol was forward-declared.
1239 ObjCList<ObjCProtocolDecl> PList;
1240 PList.set((ObjCProtocolDecl *const*)ProtoRefs, NumProtoRefs, Context);
1241 err = CheckForwardProtocolDeclarationForCircularDependency(
1242 ProtocolName, ProtocolLoc, PrevDecl->getLocation(), PList);
1243 }
1244
1245 // Create the new declaration.
1246 PDecl = ObjCProtocolDecl::Create(Context, CurContext, ProtocolName,
1247 ProtocolLoc, AtProtoInterfaceLoc,
1248 /*PrevDecl=*/PrevDecl);
1249
1250 PushOnScopeChains(PDecl, TUScope);
1251 PDecl->startDefinition();
1252 }
1253
1254 ProcessDeclAttributeList(TUScope, PDecl, AttrList);
1255 AddPragmaAttributes(TUScope, PDecl);
1256
1257 // Merge attributes from previous declarations.
1258 if (PrevDecl)
1259 mergeDeclAttributes(PDecl, PrevDecl);
1260
1261 if (!err && NumProtoRefs ) {
1262 /// Check then save referenced protocols.
1263 diagnoseUseOfProtocols(*this, PDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1264 NumProtoRefs, ProtoLocs);
1265 PDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1266 ProtoLocs, Context);
1267 }
1268
1269 CheckObjCDeclScope(PDecl);
1270 return ActOnObjCContainerStartDefinition(PDecl);
1271 }
1272
NestedProtocolHasNoDefinition(ObjCProtocolDecl * PDecl,ObjCProtocolDecl * & UndefinedProtocol)1273 static bool NestedProtocolHasNoDefinition(ObjCProtocolDecl *PDecl,
1274 ObjCProtocolDecl *&UndefinedProtocol) {
1275 if (!PDecl->hasDefinition() ||
1276 !PDecl->getDefinition()->isUnconditionallyVisible()) {
1277 UndefinedProtocol = PDecl;
1278 return true;
1279 }
1280
1281 for (auto *PI : PDecl->protocols())
1282 if (NestedProtocolHasNoDefinition(PI, UndefinedProtocol)) {
1283 UndefinedProtocol = PI;
1284 return true;
1285 }
1286 return false;
1287 }
1288
1289 /// FindProtocolDeclaration - This routine looks up protocols and
1290 /// issues an error if they are not declared. It returns list of
1291 /// protocol declarations in its 'Protocols' argument.
1292 void
FindProtocolDeclaration(bool WarnOnDeclarations,bool ForObjCContainer,ArrayRef<IdentifierLocPair> ProtocolId,SmallVectorImpl<Decl * > & Protocols)1293 Sema::FindProtocolDeclaration(bool WarnOnDeclarations, bool ForObjCContainer,
1294 ArrayRef<IdentifierLocPair> ProtocolId,
1295 SmallVectorImpl<Decl *> &Protocols) {
1296 for (const IdentifierLocPair &Pair : ProtocolId) {
1297 ObjCProtocolDecl *PDecl = LookupProtocol(Pair.first, Pair.second);
1298 if (!PDecl) {
1299 DeclFilterCCC<ObjCProtocolDecl> CCC{};
1300 TypoCorrection Corrected = CorrectTypo(
1301 DeclarationNameInfo(Pair.first, Pair.second), LookupObjCProtocolName,
1302 TUScope, nullptr, CCC, CTK_ErrorRecovery);
1303 if ((PDecl = Corrected.getCorrectionDeclAs<ObjCProtocolDecl>()))
1304 diagnoseTypo(Corrected, PDiag(diag::err_undeclared_protocol_suggest)
1305 << Pair.first);
1306 }
1307
1308 if (!PDecl) {
1309 Diag(Pair.second, diag::err_undeclared_protocol) << Pair.first;
1310 continue;
1311 }
1312 // If this is a forward protocol declaration, get its definition.
1313 if (!PDecl->isThisDeclarationADefinition() && PDecl->getDefinition())
1314 PDecl = PDecl->getDefinition();
1315
1316 // For an objc container, delay protocol reference checking until after we
1317 // can set the objc decl as the availability context, otherwise check now.
1318 if (!ForObjCContainer) {
1319 (void)DiagnoseUseOfDecl(PDecl, Pair.second);
1320 }
1321
1322 // If this is a forward declaration and we are supposed to warn in this
1323 // case, do it.
1324 // FIXME: Recover nicely in the hidden case.
1325 ObjCProtocolDecl *UndefinedProtocol;
1326
1327 if (WarnOnDeclarations &&
1328 NestedProtocolHasNoDefinition(PDecl, UndefinedProtocol)) {
1329 Diag(Pair.second, diag::warn_undef_protocolref) << Pair.first;
1330 Diag(UndefinedProtocol->getLocation(), diag::note_protocol_decl_undefined)
1331 << UndefinedProtocol;
1332 }
1333 Protocols.push_back(PDecl);
1334 }
1335 }
1336
1337 namespace {
1338 // Callback to only accept typo corrections that are either
1339 // Objective-C protocols or valid Objective-C type arguments.
1340 class ObjCTypeArgOrProtocolValidatorCCC final
1341 : public CorrectionCandidateCallback {
1342 ASTContext &Context;
1343 Sema::LookupNameKind LookupKind;
1344 public:
ObjCTypeArgOrProtocolValidatorCCC(ASTContext & context,Sema::LookupNameKind lookupKind)1345 ObjCTypeArgOrProtocolValidatorCCC(ASTContext &context,
1346 Sema::LookupNameKind lookupKind)
1347 : Context(context), LookupKind(lookupKind) { }
1348
ValidateCandidate(const TypoCorrection & candidate)1349 bool ValidateCandidate(const TypoCorrection &candidate) override {
1350 // If we're allowed to find protocols and we have a protocol, accept it.
1351 if (LookupKind != Sema::LookupOrdinaryName) {
1352 if (candidate.getCorrectionDeclAs<ObjCProtocolDecl>())
1353 return true;
1354 }
1355
1356 // If we're allowed to find type names and we have one, accept it.
1357 if (LookupKind != Sema::LookupObjCProtocolName) {
1358 // If we have a type declaration, we might accept this result.
1359 if (auto typeDecl = candidate.getCorrectionDeclAs<TypeDecl>()) {
1360 // If we found a tag declaration outside of C++, skip it. This
1361 // can happy because we look for any name when there is no
1362 // bias to protocol or type names.
1363 if (isa<RecordDecl>(typeDecl) && !Context.getLangOpts().CPlusPlus)
1364 return false;
1365
1366 // Make sure the type is something we would accept as a type
1367 // argument.
1368 auto type = Context.getTypeDeclType(typeDecl);
1369 if (type->isObjCObjectPointerType() ||
1370 type->isBlockPointerType() ||
1371 type->isDependentType() ||
1372 type->isObjCObjectType())
1373 return true;
1374
1375 return false;
1376 }
1377
1378 // If we have an Objective-C class type, accept it; there will
1379 // be another fix to add the '*'.
1380 if (candidate.getCorrectionDeclAs<ObjCInterfaceDecl>())
1381 return true;
1382
1383 return false;
1384 }
1385
1386 return false;
1387 }
1388
clone()1389 std::unique_ptr<CorrectionCandidateCallback> clone() override {
1390 return std::make_unique<ObjCTypeArgOrProtocolValidatorCCC>(*this);
1391 }
1392 };
1393 } // end anonymous namespace
1394
DiagnoseTypeArgsAndProtocols(IdentifierInfo * ProtocolId,SourceLocation ProtocolLoc,IdentifierInfo * TypeArgId,SourceLocation TypeArgLoc,bool SelectProtocolFirst)1395 void Sema::DiagnoseTypeArgsAndProtocols(IdentifierInfo *ProtocolId,
1396 SourceLocation ProtocolLoc,
1397 IdentifierInfo *TypeArgId,
1398 SourceLocation TypeArgLoc,
1399 bool SelectProtocolFirst) {
1400 Diag(TypeArgLoc, diag::err_objc_type_args_and_protocols)
1401 << SelectProtocolFirst << TypeArgId << ProtocolId
1402 << SourceRange(ProtocolLoc);
1403 }
1404
actOnObjCTypeArgsOrProtocolQualifiers(Scope * S,ParsedType baseType,SourceLocation lAngleLoc,ArrayRef<IdentifierInfo * > identifiers,ArrayRef<SourceLocation> identifierLocs,SourceLocation rAngleLoc,SourceLocation & typeArgsLAngleLoc,SmallVectorImpl<ParsedType> & typeArgs,SourceLocation & typeArgsRAngleLoc,SourceLocation & protocolLAngleLoc,SmallVectorImpl<Decl * > & protocols,SourceLocation & protocolRAngleLoc,bool warnOnIncompleteProtocols)1405 void Sema::actOnObjCTypeArgsOrProtocolQualifiers(
1406 Scope *S,
1407 ParsedType baseType,
1408 SourceLocation lAngleLoc,
1409 ArrayRef<IdentifierInfo *> identifiers,
1410 ArrayRef<SourceLocation> identifierLocs,
1411 SourceLocation rAngleLoc,
1412 SourceLocation &typeArgsLAngleLoc,
1413 SmallVectorImpl<ParsedType> &typeArgs,
1414 SourceLocation &typeArgsRAngleLoc,
1415 SourceLocation &protocolLAngleLoc,
1416 SmallVectorImpl<Decl *> &protocols,
1417 SourceLocation &protocolRAngleLoc,
1418 bool warnOnIncompleteProtocols) {
1419 // Local function that updates the declaration specifiers with
1420 // protocol information.
1421 unsigned numProtocolsResolved = 0;
1422 auto resolvedAsProtocols = [&] {
1423 assert(numProtocolsResolved == identifiers.size() && "Unresolved protocols");
1424
1425 // Determine whether the base type is a parameterized class, in
1426 // which case we want to warn about typos such as
1427 // "NSArray<NSObject>" (that should be NSArray<NSObject *>).
1428 ObjCInterfaceDecl *baseClass = nullptr;
1429 QualType base = GetTypeFromParser(baseType, nullptr);
1430 bool allAreTypeNames = false;
1431 SourceLocation firstClassNameLoc;
1432 if (!base.isNull()) {
1433 if (const auto *objcObjectType = base->getAs<ObjCObjectType>()) {
1434 baseClass = objcObjectType->getInterface();
1435 if (baseClass) {
1436 if (auto typeParams = baseClass->getTypeParamList()) {
1437 if (typeParams->size() == numProtocolsResolved) {
1438 // Note that we should be looking for type names, too.
1439 allAreTypeNames = true;
1440 }
1441 }
1442 }
1443 }
1444 }
1445
1446 for (unsigned i = 0, n = protocols.size(); i != n; ++i) {
1447 ObjCProtocolDecl *&proto
1448 = reinterpret_cast<ObjCProtocolDecl *&>(protocols[i]);
1449 // For an objc container, delay protocol reference checking until after we
1450 // can set the objc decl as the availability context, otherwise check now.
1451 if (!warnOnIncompleteProtocols) {
1452 (void)DiagnoseUseOfDecl(proto, identifierLocs[i]);
1453 }
1454
1455 // If this is a forward protocol declaration, get its definition.
1456 if (!proto->isThisDeclarationADefinition() && proto->getDefinition())
1457 proto = proto->getDefinition();
1458
1459 // If this is a forward declaration and we are supposed to warn in this
1460 // case, do it.
1461 // FIXME: Recover nicely in the hidden case.
1462 ObjCProtocolDecl *forwardDecl = nullptr;
1463 if (warnOnIncompleteProtocols &&
1464 NestedProtocolHasNoDefinition(proto, forwardDecl)) {
1465 Diag(identifierLocs[i], diag::warn_undef_protocolref)
1466 << proto->getDeclName();
1467 Diag(forwardDecl->getLocation(), diag::note_protocol_decl_undefined)
1468 << forwardDecl;
1469 }
1470
1471 // If everything this far has been a type name (and we care
1472 // about such things), check whether this name refers to a type
1473 // as well.
1474 if (allAreTypeNames) {
1475 if (auto *decl = LookupSingleName(S, identifiers[i], identifierLocs[i],
1476 LookupOrdinaryName)) {
1477 if (isa<ObjCInterfaceDecl>(decl)) {
1478 if (firstClassNameLoc.isInvalid())
1479 firstClassNameLoc = identifierLocs[i];
1480 } else if (!isa<TypeDecl>(decl)) {
1481 // Not a type.
1482 allAreTypeNames = false;
1483 }
1484 } else {
1485 allAreTypeNames = false;
1486 }
1487 }
1488 }
1489
1490 // All of the protocols listed also have type names, and at least
1491 // one is an Objective-C class name. Check whether all of the
1492 // protocol conformances are declared by the base class itself, in
1493 // which case we warn.
1494 if (allAreTypeNames && firstClassNameLoc.isValid()) {
1495 llvm::SmallPtrSet<ObjCProtocolDecl*, 8> knownProtocols;
1496 Context.CollectInheritedProtocols(baseClass, knownProtocols);
1497 bool allProtocolsDeclared = true;
1498 for (auto proto : protocols) {
1499 if (knownProtocols.count(static_cast<ObjCProtocolDecl *>(proto)) == 0) {
1500 allProtocolsDeclared = false;
1501 break;
1502 }
1503 }
1504
1505 if (allProtocolsDeclared) {
1506 Diag(firstClassNameLoc, diag::warn_objc_redundant_qualified_class_type)
1507 << baseClass->getDeclName() << SourceRange(lAngleLoc, rAngleLoc)
1508 << FixItHint::CreateInsertion(getLocForEndOfToken(firstClassNameLoc),
1509 " *");
1510 }
1511 }
1512
1513 protocolLAngleLoc = lAngleLoc;
1514 protocolRAngleLoc = rAngleLoc;
1515 assert(protocols.size() == identifierLocs.size());
1516 };
1517
1518 // Attempt to resolve all of the identifiers as protocols.
1519 for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1520 ObjCProtocolDecl *proto = LookupProtocol(identifiers[i], identifierLocs[i]);
1521 protocols.push_back(proto);
1522 if (proto)
1523 ++numProtocolsResolved;
1524 }
1525
1526 // If all of the names were protocols, these were protocol qualifiers.
1527 if (numProtocolsResolved == identifiers.size())
1528 return resolvedAsProtocols();
1529
1530 // Attempt to resolve all of the identifiers as type names or
1531 // Objective-C class names. The latter is technically ill-formed,
1532 // but is probably something like \c NSArray<NSView *> missing the
1533 // \c*.
1534 typedef llvm::PointerUnion<TypeDecl *, ObjCInterfaceDecl *> TypeOrClassDecl;
1535 SmallVector<TypeOrClassDecl, 4> typeDecls;
1536 unsigned numTypeDeclsResolved = 0;
1537 for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1538 NamedDecl *decl = LookupSingleName(S, identifiers[i], identifierLocs[i],
1539 LookupOrdinaryName);
1540 if (!decl) {
1541 typeDecls.push_back(TypeOrClassDecl());
1542 continue;
1543 }
1544
1545 if (auto typeDecl = dyn_cast<TypeDecl>(decl)) {
1546 typeDecls.push_back(typeDecl);
1547 ++numTypeDeclsResolved;
1548 continue;
1549 }
1550
1551 if (auto objcClass = dyn_cast<ObjCInterfaceDecl>(decl)) {
1552 typeDecls.push_back(objcClass);
1553 ++numTypeDeclsResolved;
1554 continue;
1555 }
1556
1557 typeDecls.push_back(TypeOrClassDecl());
1558 }
1559
1560 AttributeFactory attrFactory;
1561
1562 // Local function that forms a reference to the given type or
1563 // Objective-C class declaration.
1564 auto resolveTypeReference = [&](TypeOrClassDecl typeDecl, SourceLocation loc)
1565 -> TypeResult {
1566 // Form declaration specifiers. They simply refer to the type.
1567 DeclSpec DS(attrFactory);
1568 const char* prevSpec; // unused
1569 unsigned diagID; // unused
1570 QualType type;
1571 if (auto *actualTypeDecl = typeDecl.dyn_cast<TypeDecl *>())
1572 type = Context.getTypeDeclType(actualTypeDecl);
1573 else
1574 type = Context.getObjCInterfaceType(typeDecl.get<ObjCInterfaceDecl *>());
1575 TypeSourceInfo *parsedTSInfo = Context.getTrivialTypeSourceInfo(type, loc);
1576 ParsedType parsedType = CreateParsedType(type, parsedTSInfo);
1577 DS.SetTypeSpecType(DeclSpec::TST_typename, loc, prevSpec, diagID,
1578 parsedType, Context.getPrintingPolicy());
1579 // Use the identifier location for the type source range.
1580 DS.SetRangeStart(loc);
1581 DS.SetRangeEnd(loc);
1582
1583 // Form the declarator.
1584 Declarator D(DS, DeclaratorContext::TypeNameContext);
1585
1586 // If we have a typedef of an Objective-C class type that is missing a '*',
1587 // add the '*'.
1588 if (type->getAs<ObjCInterfaceType>()) {
1589 SourceLocation starLoc = getLocForEndOfToken(loc);
1590 D.AddTypeInfo(DeclaratorChunk::getPointer(/*TypeQuals=*/0, starLoc,
1591 SourceLocation(),
1592 SourceLocation(),
1593 SourceLocation(),
1594 SourceLocation(),
1595 SourceLocation()),
1596 starLoc);
1597
1598 // Diagnose the missing '*'.
1599 Diag(loc, diag::err_objc_type_arg_missing_star)
1600 << type
1601 << FixItHint::CreateInsertion(starLoc, " *");
1602 }
1603
1604 // Convert this to a type.
1605 return ActOnTypeName(S, D);
1606 };
1607
1608 // Local function that updates the declaration specifiers with
1609 // type argument information.
1610 auto resolvedAsTypeDecls = [&] {
1611 // We did not resolve these as protocols.
1612 protocols.clear();
1613
1614 assert(numTypeDeclsResolved == identifiers.size() && "Unresolved type decl");
1615 // Map type declarations to type arguments.
1616 for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1617 // Map type reference to a type.
1618 TypeResult type = resolveTypeReference(typeDecls[i], identifierLocs[i]);
1619 if (!type.isUsable()) {
1620 typeArgs.clear();
1621 return;
1622 }
1623
1624 typeArgs.push_back(type.get());
1625 }
1626
1627 typeArgsLAngleLoc = lAngleLoc;
1628 typeArgsRAngleLoc = rAngleLoc;
1629 };
1630
1631 // If all of the identifiers can be resolved as type names or
1632 // Objective-C class names, we have type arguments.
1633 if (numTypeDeclsResolved == identifiers.size())
1634 return resolvedAsTypeDecls();
1635
1636 // Error recovery: some names weren't found, or we have a mix of
1637 // type and protocol names. Go resolve all of the unresolved names
1638 // and complain if we can't find a consistent answer.
1639 LookupNameKind lookupKind = LookupAnyName;
1640 for (unsigned i = 0, n = identifiers.size(); i != n; ++i) {
1641 // If we already have a protocol or type. Check whether it is the
1642 // right thing.
1643 if (protocols[i] || typeDecls[i]) {
1644 // If we haven't figured out whether we want types or protocols
1645 // yet, try to figure it out from this name.
1646 if (lookupKind == LookupAnyName) {
1647 // If this name refers to both a protocol and a type (e.g., \c
1648 // NSObject), don't conclude anything yet.
1649 if (protocols[i] && typeDecls[i])
1650 continue;
1651
1652 // Otherwise, let this name decide whether we'll be correcting
1653 // toward types or protocols.
1654 lookupKind = protocols[i] ? LookupObjCProtocolName
1655 : LookupOrdinaryName;
1656 continue;
1657 }
1658
1659 // If we want protocols and we have a protocol, there's nothing
1660 // more to do.
1661 if (lookupKind == LookupObjCProtocolName && protocols[i])
1662 continue;
1663
1664 // If we want types and we have a type declaration, there's
1665 // nothing more to do.
1666 if (lookupKind == LookupOrdinaryName && typeDecls[i])
1667 continue;
1668
1669 // We have a conflict: some names refer to protocols and others
1670 // refer to types.
1671 DiagnoseTypeArgsAndProtocols(identifiers[0], identifierLocs[0],
1672 identifiers[i], identifierLocs[i],
1673 protocols[i] != nullptr);
1674
1675 protocols.clear();
1676 typeArgs.clear();
1677 return;
1678 }
1679
1680 // Perform typo correction on the name.
1681 ObjCTypeArgOrProtocolValidatorCCC CCC(Context, lookupKind);
1682 TypoCorrection corrected =
1683 CorrectTypo(DeclarationNameInfo(identifiers[i], identifierLocs[i]),
1684 lookupKind, S, nullptr, CCC, CTK_ErrorRecovery);
1685 if (corrected) {
1686 // Did we find a protocol?
1687 if (auto proto = corrected.getCorrectionDeclAs<ObjCProtocolDecl>()) {
1688 diagnoseTypo(corrected,
1689 PDiag(diag::err_undeclared_protocol_suggest)
1690 << identifiers[i]);
1691 lookupKind = LookupObjCProtocolName;
1692 protocols[i] = proto;
1693 ++numProtocolsResolved;
1694 continue;
1695 }
1696
1697 // Did we find a type?
1698 if (auto typeDecl = corrected.getCorrectionDeclAs<TypeDecl>()) {
1699 diagnoseTypo(corrected,
1700 PDiag(diag::err_unknown_typename_suggest)
1701 << identifiers[i]);
1702 lookupKind = LookupOrdinaryName;
1703 typeDecls[i] = typeDecl;
1704 ++numTypeDeclsResolved;
1705 continue;
1706 }
1707
1708 // Did we find an Objective-C class?
1709 if (auto objcClass = corrected.getCorrectionDeclAs<ObjCInterfaceDecl>()) {
1710 diagnoseTypo(corrected,
1711 PDiag(diag::err_unknown_type_or_class_name_suggest)
1712 << identifiers[i] << true);
1713 lookupKind = LookupOrdinaryName;
1714 typeDecls[i] = objcClass;
1715 ++numTypeDeclsResolved;
1716 continue;
1717 }
1718 }
1719
1720 // We couldn't find anything.
1721 Diag(identifierLocs[i],
1722 (lookupKind == LookupAnyName ? diag::err_objc_type_arg_missing
1723 : lookupKind == LookupObjCProtocolName ? diag::err_undeclared_protocol
1724 : diag::err_unknown_typename))
1725 << identifiers[i];
1726 protocols.clear();
1727 typeArgs.clear();
1728 return;
1729 }
1730
1731 // If all of the names were (corrected to) protocols, these were
1732 // protocol qualifiers.
1733 if (numProtocolsResolved == identifiers.size())
1734 return resolvedAsProtocols();
1735
1736 // Otherwise, all of the names were (corrected to) types.
1737 assert(numTypeDeclsResolved == identifiers.size() && "Not all types?");
1738 return resolvedAsTypeDecls();
1739 }
1740
1741 /// DiagnoseClassExtensionDupMethods - Check for duplicate declaration of
1742 /// a class method in its extension.
1743 ///
DiagnoseClassExtensionDupMethods(ObjCCategoryDecl * CAT,ObjCInterfaceDecl * ID)1744 void Sema::DiagnoseClassExtensionDupMethods(ObjCCategoryDecl *CAT,
1745 ObjCInterfaceDecl *ID) {
1746 if (!ID)
1747 return; // Possibly due to previous error
1748
1749 llvm::DenseMap<Selector, const ObjCMethodDecl*> MethodMap;
1750 for (auto *MD : ID->methods())
1751 MethodMap[MD->getSelector()] = MD;
1752
1753 if (MethodMap.empty())
1754 return;
1755 for (const auto *Method : CAT->methods()) {
1756 const ObjCMethodDecl *&PrevMethod = MethodMap[Method->getSelector()];
1757 if (PrevMethod &&
1758 (PrevMethod->isInstanceMethod() == Method->isInstanceMethod()) &&
1759 !MatchTwoMethodDeclarations(Method, PrevMethod)) {
1760 Diag(Method->getLocation(), diag::err_duplicate_method_decl)
1761 << Method->getDeclName();
1762 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
1763 }
1764 }
1765 }
1766
1767 /// ActOnForwardProtocolDeclaration - Handle \@protocol foo;
1768 Sema::DeclGroupPtrTy
ActOnForwardProtocolDeclaration(SourceLocation AtProtocolLoc,ArrayRef<IdentifierLocPair> IdentList,const ParsedAttributesView & attrList)1769 Sema::ActOnForwardProtocolDeclaration(SourceLocation AtProtocolLoc,
1770 ArrayRef<IdentifierLocPair> IdentList,
1771 const ParsedAttributesView &attrList) {
1772 SmallVector<Decl *, 8> DeclsInGroup;
1773 for (const IdentifierLocPair &IdentPair : IdentList) {
1774 IdentifierInfo *Ident = IdentPair.first;
1775 ObjCProtocolDecl *PrevDecl = LookupProtocol(Ident, IdentPair.second,
1776 forRedeclarationInCurContext());
1777 ObjCProtocolDecl *PDecl
1778 = ObjCProtocolDecl::Create(Context, CurContext, Ident,
1779 IdentPair.second, AtProtocolLoc,
1780 PrevDecl);
1781
1782 PushOnScopeChains(PDecl, TUScope);
1783 CheckObjCDeclScope(PDecl);
1784
1785 ProcessDeclAttributeList(TUScope, PDecl, attrList);
1786 AddPragmaAttributes(TUScope, PDecl);
1787
1788 if (PrevDecl)
1789 mergeDeclAttributes(PDecl, PrevDecl);
1790
1791 DeclsInGroup.push_back(PDecl);
1792 }
1793
1794 return BuildDeclaratorGroup(DeclsInGroup);
1795 }
1796
ActOnStartCategoryInterface(SourceLocation AtInterfaceLoc,IdentifierInfo * ClassName,SourceLocation ClassLoc,ObjCTypeParamList * typeParamList,IdentifierInfo * CategoryName,SourceLocation CategoryLoc,Decl * const * ProtoRefs,unsigned NumProtoRefs,const SourceLocation * ProtoLocs,SourceLocation EndProtoLoc,const ParsedAttributesView & AttrList)1797 Decl *Sema::ActOnStartCategoryInterface(
1798 SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName,
1799 SourceLocation ClassLoc, ObjCTypeParamList *typeParamList,
1800 IdentifierInfo *CategoryName, SourceLocation CategoryLoc,
1801 Decl *const *ProtoRefs, unsigned NumProtoRefs,
1802 const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc,
1803 const ParsedAttributesView &AttrList) {
1804 ObjCCategoryDecl *CDecl;
1805 ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc, true);
1806
1807 /// Check that class of this category is already completely declared.
1808
1809 if (!IDecl
1810 || RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl),
1811 diag::err_category_forward_interface,
1812 CategoryName == nullptr)) {
1813 // Create an invalid ObjCCategoryDecl to serve as context for
1814 // the enclosing method declarations. We mark the decl invalid
1815 // to make it clear that this isn't a valid AST.
1816 CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc,
1817 ClassLoc, CategoryLoc, CategoryName,
1818 IDecl, typeParamList);
1819 CDecl->setInvalidDecl();
1820 CurContext->addDecl(CDecl);
1821
1822 if (!IDecl)
1823 Diag(ClassLoc, diag::err_undef_interface) << ClassName;
1824 return ActOnObjCContainerStartDefinition(CDecl);
1825 }
1826
1827 if (!CategoryName && IDecl->getImplementation()) {
1828 Diag(ClassLoc, diag::err_class_extension_after_impl) << ClassName;
1829 Diag(IDecl->getImplementation()->getLocation(),
1830 diag::note_implementation_declared);
1831 }
1832
1833 if (CategoryName) {
1834 /// Check for duplicate interface declaration for this category
1835 if (ObjCCategoryDecl *Previous
1836 = IDecl->FindCategoryDeclaration(CategoryName)) {
1837 // Class extensions can be declared multiple times, categories cannot.
1838 Diag(CategoryLoc, diag::warn_dup_category_def)
1839 << ClassName << CategoryName;
1840 Diag(Previous->getLocation(), diag::note_previous_definition);
1841 }
1842 }
1843
1844 // If we have a type parameter list, check it.
1845 if (typeParamList) {
1846 if (auto prevTypeParamList = IDecl->getTypeParamList()) {
1847 if (checkTypeParamListConsistency(*this, prevTypeParamList, typeParamList,
1848 CategoryName
1849 ? TypeParamListContext::Category
1850 : TypeParamListContext::Extension))
1851 typeParamList = nullptr;
1852 } else {
1853 Diag(typeParamList->getLAngleLoc(),
1854 diag::err_objc_parameterized_category_nonclass)
1855 << (CategoryName != nullptr)
1856 << ClassName
1857 << typeParamList->getSourceRange();
1858
1859 typeParamList = nullptr;
1860 }
1861 }
1862
1863 CDecl = ObjCCategoryDecl::Create(Context, CurContext, AtInterfaceLoc,
1864 ClassLoc, CategoryLoc, CategoryName, IDecl,
1865 typeParamList);
1866 // FIXME: PushOnScopeChains?
1867 CurContext->addDecl(CDecl);
1868
1869 // Process the attributes before looking at protocols to ensure that the
1870 // availability attribute is attached to the category to provide availability
1871 // checking for protocol uses.
1872 ProcessDeclAttributeList(TUScope, CDecl, AttrList);
1873 AddPragmaAttributes(TUScope, CDecl);
1874
1875 if (NumProtoRefs) {
1876 diagnoseUseOfProtocols(*this, CDecl, (ObjCProtocolDecl*const*)ProtoRefs,
1877 NumProtoRefs, ProtoLocs);
1878 CDecl->setProtocolList((ObjCProtocolDecl*const*)ProtoRefs, NumProtoRefs,
1879 ProtoLocs, Context);
1880 // Protocols in the class extension belong to the class.
1881 if (CDecl->IsClassExtension())
1882 IDecl->mergeClassExtensionProtocolList((ObjCProtocolDecl*const*)ProtoRefs,
1883 NumProtoRefs, Context);
1884 }
1885
1886 CheckObjCDeclScope(CDecl);
1887 return ActOnObjCContainerStartDefinition(CDecl);
1888 }
1889
1890 /// ActOnStartCategoryImplementation - Perform semantic checks on the
1891 /// category implementation declaration and build an ObjCCategoryImplDecl
1892 /// object.
ActOnStartCategoryImplementation(SourceLocation AtCatImplLoc,IdentifierInfo * ClassName,SourceLocation ClassLoc,IdentifierInfo * CatName,SourceLocation CatLoc,const ParsedAttributesView & Attrs)1893 Decl *Sema::ActOnStartCategoryImplementation(
1894 SourceLocation AtCatImplLoc,
1895 IdentifierInfo *ClassName, SourceLocation ClassLoc,
1896 IdentifierInfo *CatName, SourceLocation CatLoc,
1897 const ParsedAttributesView &Attrs) {
1898 ObjCInterfaceDecl *IDecl = getObjCInterfaceDecl(ClassName, ClassLoc, true);
1899 ObjCCategoryDecl *CatIDecl = nullptr;
1900 if (IDecl && IDecl->hasDefinition()) {
1901 CatIDecl = IDecl->FindCategoryDeclaration(CatName);
1902 if (!CatIDecl) {
1903 // Category @implementation with no corresponding @interface.
1904 // Create and install one.
1905 CatIDecl = ObjCCategoryDecl::Create(Context, CurContext, AtCatImplLoc,
1906 ClassLoc, CatLoc,
1907 CatName, IDecl,
1908 /*typeParamList=*/nullptr);
1909 CatIDecl->setImplicit();
1910 }
1911 }
1912
1913 ObjCCategoryImplDecl *CDecl =
1914 ObjCCategoryImplDecl::Create(Context, CurContext, CatName, IDecl,
1915 ClassLoc, AtCatImplLoc, CatLoc);
1916 /// Check that class of this category is already completely declared.
1917 if (!IDecl) {
1918 Diag(ClassLoc, diag::err_undef_interface) << ClassName;
1919 CDecl->setInvalidDecl();
1920 } else if (RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl),
1921 diag::err_undef_interface)) {
1922 CDecl->setInvalidDecl();
1923 }
1924
1925 ProcessDeclAttributeList(TUScope, CDecl, Attrs);
1926 AddPragmaAttributes(TUScope, CDecl);
1927
1928 // FIXME: PushOnScopeChains?
1929 CurContext->addDecl(CDecl);
1930
1931 // If the interface has the objc_runtime_visible attribute, we
1932 // cannot implement a category for it.
1933 if (IDecl && IDecl->hasAttr<ObjCRuntimeVisibleAttr>()) {
1934 Diag(ClassLoc, diag::err_objc_runtime_visible_category)
1935 << IDecl->getDeclName();
1936 }
1937
1938 /// Check that CatName, category name, is not used in another implementation.
1939 if (CatIDecl) {
1940 if (CatIDecl->getImplementation()) {
1941 Diag(ClassLoc, diag::err_dup_implementation_category) << ClassName
1942 << CatName;
1943 Diag(CatIDecl->getImplementation()->getLocation(),
1944 diag::note_previous_definition);
1945 CDecl->setInvalidDecl();
1946 } else {
1947 CatIDecl->setImplementation(CDecl);
1948 // Warn on implementating category of deprecated class under
1949 // -Wdeprecated-implementations flag.
1950 DiagnoseObjCImplementedDeprecations(*this, CatIDecl,
1951 CDecl->getLocation());
1952 }
1953 }
1954
1955 CheckObjCDeclScope(CDecl);
1956 return ActOnObjCContainerStartDefinition(CDecl);
1957 }
1958
ActOnStartClassImplementation(SourceLocation AtClassImplLoc,IdentifierInfo * ClassName,SourceLocation ClassLoc,IdentifierInfo * SuperClassname,SourceLocation SuperClassLoc,const ParsedAttributesView & Attrs)1959 Decl *Sema::ActOnStartClassImplementation(
1960 SourceLocation AtClassImplLoc,
1961 IdentifierInfo *ClassName, SourceLocation ClassLoc,
1962 IdentifierInfo *SuperClassname,
1963 SourceLocation SuperClassLoc,
1964 const ParsedAttributesView &Attrs) {
1965 ObjCInterfaceDecl *IDecl = nullptr;
1966 // Check for another declaration kind with the same name.
1967 NamedDecl *PrevDecl
1968 = LookupSingleName(TUScope, ClassName, ClassLoc, LookupOrdinaryName,
1969 forRedeclarationInCurContext());
1970 if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
1971 Diag(ClassLoc, diag::err_redefinition_different_kind) << ClassName;
1972 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
1973 } else if ((IDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl))) {
1974 // FIXME: This will produce an error if the definition of the interface has
1975 // been imported from a module but is not visible.
1976 RequireCompleteType(ClassLoc, Context.getObjCInterfaceType(IDecl),
1977 diag::warn_undef_interface);
1978 } else {
1979 // We did not find anything with the name ClassName; try to correct for
1980 // typos in the class name.
1981 ObjCInterfaceValidatorCCC CCC{};
1982 TypoCorrection Corrected =
1983 CorrectTypo(DeclarationNameInfo(ClassName, ClassLoc),
1984 LookupOrdinaryName, TUScope, nullptr, CCC, CTK_NonError);
1985 if (Corrected.getCorrectionDeclAs<ObjCInterfaceDecl>()) {
1986 // Suggest the (potentially) correct interface name. Don't provide a
1987 // code-modification hint or use the typo name for recovery, because
1988 // this is just a warning. The program may actually be correct.
1989 diagnoseTypo(Corrected,
1990 PDiag(diag::warn_undef_interface_suggest) << ClassName,
1991 /*ErrorRecovery*/false);
1992 } else {
1993 Diag(ClassLoc, diag::warn_undef_interface) << ClassName;
1994 }
1995 }
1996
1997 // Check that super class name is valid class name
1998 ObjCInterfaceDecl *SDecl = nullptr;
1999 if (SuperClassname) {
2000 // Check if a different kind of symbol declared in this scope.
2001 PrevDecl = LookupSingleName(TUScope, SuperClassname, SuperClassLoc,
2002 LookupOrdinaryName);
2003 if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
2004 Diag(SuperClassLoc, diag::err_redefinition_different_kind)
2005 << SuperClassname;
2006 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
2007 } else {
2008 SDecl = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
2009 if (SDecl && !SDecl->hasDefinition())
2010 SDecl = nullptr;
2011 if (!SDecl)
2012 Diag(SuperClassLoc, diag::err_undef_superclass)
2013 << SuperClassname << ClassName;
2014 else if (IDecl && !declaresSameEntity(IDecl->getSuperClass(), SDecl)) {
2015 // This implementation and its interface do not have the same
2016 // super class.
2017 Diag(SuperClassLoc, diag::err_conflicting_super_class)
2018 << SDecl->getDeclName();
2019 Diag(SDecl->getLocation(), diag::note_previous_definition);
2020 }
2021 }
2022 }
2023
2024 if (!IDecl) {
2025 // Legacy case of @implementation with no corresponding @interface.
2026 // Build, chain & install the interface decl into the identifier.
2027
2028 // FIXME: Do we support attributes on the @implementation? If so we should
2029 // copy them over.
2030 IDecl = ObjCInterfaceDecl::Create(Context, CurContext, AtClassImplLoc,
2031 ClassName, /*typeParamList=*/nullptr,
2032 /*PrevDecl=*/nullptr, ClassLoc,
2033 true);
2034 AddPragmaAttributes(TUScope, IDecl);
2035 IDecl->startDefinition();
2036 if (SDecl) {
2037 IDecl->setSuperClass(Context.getTrivialTypeSourceInfo(
2038 Context.getObjCInterfaceType(SDecl),
2039 SuperClassLoc));
2040 IDecl->setEndOfDefinitionLoc(SuperClassLoc);
2041 } else {
2042 IDecl->setEndOfDefinitionLoc(ClassLoc);
2043 }
2044
2045 PushOnScopeChains(IDecl, TUScope);
2046 } else {
2047 // Mark the interface as being completed, even if it was just as
2048 // @class ....;
2049 // declaration; the user cannot reopen it.
2050 if (!IDecl->hasDefinition())
2051 IDecl->startDefinition();
2052 }
2053
2054 ObjCImplementationDecl* IMPDecl =
2055 ObjCImplementationDecl::Create(Context, CurContext, IDecl, SDecl,
2056 ClassLoc, AtClassImplLoc, SuperClassLoc);
2057
2058 ProcessDeclAttributeList(TUScope, IMPDecl, Attrs);
2059 AddPragmaAttributes(TUScope, IMPDecl);
2060
2061 if (CheckObjCDeclScope(IMPDecl))
2062 return ActOnObjCContainerStartDefinition(IMPDecl);
2063
2064 // Check that there is no duplicate implementation of this class.
2065 if (IDecl->getImplementation()) {
2066 // FIXME: Don't leak everything!
2067 Diag(ClassLoc, diag::err_dup_implementation_class) << ClassName;
2068 Diag(IDecl->getImplementation()->getLocation(),
2069 diag::note_previous_definition);
2070 IMPDecl->setInvalidDecl();
2071 } else { // add it to the list.
2072 IDecl->setImplementation(IMPDecl);
2073 PushOnScopeChains(IMPDecl, TUScope);
2074 // Warn on implementating deprecated class under
2075 // -Wdeprecated-implementations flag.
2076 DiagnoseObjCImplementedDeprecations(*this, IDecl, IMPDecl->getLocation());
2077 }
2078
2079 // If the superclass has the objc_runtime_visible attribute, we
2080 // cannot implement a subclass of it.
2081 if (IDecl->getSuperClass() &&
2082 IDecl->getSuperClass()->hasAttr<ObjCRuntimeVisibleAttr>()) {
2083 Diag(ClassLoc, diag::err_objc_runtime_visible_subclass)
2084 << IDecl->getDeclName()
2085 << IDecl->getSuperClass()->getDeclName();
2086 }
2087
2088 return ActOnObjCContainerStartDefinition(IMPDecl);
2089 }
2090
2091 Sema::DeclGroupPtrTy
ActOnFinishObjCImplementation(Decl * ObjCImpDecl,ArrayRef<Decl * > Decls)2092 Sema::ActOnFinishObjCImplementation(Decl *ObjCImpDecl, ArrayRef<Decl *> Decls) {
2093 SmallVector<Decl *, 64> DeclsInGroup;
2094 DeclsInGroup.reserve(Decls.size() + 1);
2095
2096 for (unsigned i = 0, e = Decls.size(); i != e; ++i) {
2097 Decl *Dcl = Decls[i];
2098 if (!Dcl)
2099 continue;
2100 if (Dcl->getDeclContext()->isFileContext())
2101 Dcl->setTopLevelDeclInObjCContainer();
2102 DeclsInGroup.push_back(Dcl);
2103 }
2104
2105 DeclsInGroup.push_back(ObjCImpDecl);
2106
2107 return BuildDeclaratorGroup(DeclsInGroup);
2108 }
2109
CheckImplementationIvars(ObjCImplementationDecl * ImpDecl,ObjCIvarDecl ** ivars,unsigned numIvars,SourceLocation RBrace)2110 void Sema::CheckImplementationIvars(ObjCImplementationDecl *ImpDecl,
2111 ObjCIvarDecl **ivars, unsigned numIvars,
2112 SourceLocation RBrace) {
2113 assert(ImpDecl && "missing implementation decl");
2114 ObjCInterfaceDecl* IDecl = ImpDecl->getClassInterface();
2115 if (!IDecl)
2116 return;
2117 /// Check case of non-existing \@interface decl.
2118 /// (legacy objective-c \@implementation decl without an \@interface decl).
2119 /// Add implementations's ivar to the synthesize class's ivar list.
2120 if (IDecl->isImplicitInterfaceDecl()) {
2121 IDecl->setEndOfDefinitionLoc(RBrace);
2122 // Add ivar's to class's DeclContext.
2123 for (unsigned i = 0, e = numIvars; i != e; ++i) {
2124 ivars[i]->setLexicalDeclContext(ImpDecl);
2125 IDecl->makeDeclVisibleInContext(ivars[i]);
2126 ImpDecl->addDecl(ivars[i]);
2127 }
2128
2129 return;
2130 }
2131 // If implementation has empty ivar list, just return.
2132 if (numIvars == 0)
2133 return;
2134
2135 assert(ivars && "missing @implementation ivars");
2136 if (LangOpts.ObjCRuntime.isNonFragile()) {
2137 if (ImpDecl->getSuperClass())
2138 Diag(ImpDecl->getLocation(), diag::warn_on_superclass_use);
2139 for (unsigned i = 0; i < numIvars; i++) {
2140 ObjCIvarDecl* ImplIvar = ivars[i];
2141 if (const ObjCIvarDecl *ClsIvar =
2142 IDecl->getIvarDecl(ImplIvar->getIdentifier())) {
2143 Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration);
2144 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2145 continue;
2146 }
2147 // Check class extensions (unnamed categories) for duplicate ivars.
2148 for (const auto *CDecl : IDecl->visible_extensions()) {
2149 if (const ObjCIvarDecl *ClsExtIvar =
2150 CDecl->getIvarDecl(ImplIvar->getIdentifier())) {
2151 Diag(ImplIvar->getLocation(), diag::err_duplicate_ivar_declaration);
2152 Diag(ClsExtIvar->getLocation(), diag::note_previous_definition);
2153 continue;
2154 }
2155 }
2156 // Instance ivar to Implementation's DeclContext.
2157 ImplIvar->setLexicalDeclContext(ImpDecl);
2158 IDecl->makeDeclVisibleInContext(ImplIvar);
2159 ImpDecl->addDecl(ImplIvar);
2160 }
2161 return;
2162 }
2163 // Check interface's Ivar list against those in the implementation.
2164 // names and types must match.
2165 //
2166 unsigned j = 0;
2167 ObjCInterfaceDecl::ivar_iterator
2168 IVI = IDecl->ivar_begin(), IVE = IDecl->ivar_end();
2169 for (; numIvars > 0 && IVI != IVE; ++IVI) {
2170 ObjCIvarDecl* ImplIvar = ivars[j++];
2171 ObjCIvarDecl* ClsIvar = *IVI;
2172 assert (ImplIvar && "missing implementation ivar");
2173 assert (ClsIvar && "missing class ivar");
2174
2175 // First, make sure the types match.
2176 if (!Context.hasSameType(ImplIvar->getType(), ClsIvar->getType())) {
2177 Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_type)
2178 << ImplIvar->getIdentifier()
2179 << ImplIvar->getType() << ClsIvar->getType();
2180 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2181 } else if (ImplIvar->isBitField() && ClsIvar->isBitField() &&
2182 ImplIvar->getBitWidthValue(Context) !=
2183 ClsIvar->getBitWidthValue(Context)) {
2184 Diag(ImplIvar->getBitWidth()->getBeginLoc(),
2185 diag::err_conflicting_ivar_bitwidth)
2186 << ImplIvar->getIdentifier();
2187 Diag(ClsIvar->getBitWidth()->getBeginLoc(),
2188 diag::note_previous_definition);
2189 }
2190 // Make sure the names are identical.
2191 if (ImplIvar->getIdentifier() != ClsIvar->getIdentifier()) {
2192 Diag(ImplIvar->getLocation(), diag::err_conflicting_ivar_name)
2193 << ImplIvar->getIdentifier() << ClsIvar->getIdentifier();
2194 Diag(ClsIvar->getLocation(), diag::note_previous_definition);
2195 }
2196 --numIvars;
2197 }
2198
2199 if (numIvars > 0)
2200 Diag(ivars[j]->getLocation(), diag::err_inconsistent_ivar_count);
2201 else if (IVI != IVE)
2202 Diag(IVI->getLocation(), diag::err_inconsistent_ivar_count);
2203 }
2204
WarnUndefinedMethod(Sema & S,SourceLocation ImpLoc,ObjCMethodDecl * method,bool & IncompleteImpl,unsigned DiagID,NamedDecl * NeededFor=nullptr)2205 static void WarnUndefinedMethod(Sema &S, SourceLocation ImpLoc,
2206 ObjCMethodDecl *method,
2207 bool &IncompleteImpl,
2208 unsigned DiagID,
2209 NamedDecl *NeededFor = nullptr) {
2210 // No point warning no definition of method which is 'unavailable'.
2211 if (method->getAvailability() == AR_Unavailable)
2212 return;
2213
2214 // FIXME: For now ignore 'IncompleteImpl'.
2215 // Previously we grouped all unimplemented methods under a single
2216 // warning, but some users strongly voiced that they would prefer
2217 // separate warnings. We will give that approach a try, as that
2218 // matches what we do with protocols.
2219 {
2220 const Sema::SemaDiagnosticBuilder &B = S.Diag(ImpLoc, DiagID);
2221 B << method;
2222 if (NeededFor)
2223 B << NeededFor;
2224 }
2225
2226 // Issue a note to the original declaration.
2227 SourceLocation MethodLoc = method->getBeginLoc();
2228 if (MethodLoc.isValid())
2229 S.Diag(MethodLoc, diag::note_method_declared_at) << method;
2230 }
2231
2232 /// Determines if type B can be substituted for type A. Returns true if we can
2233 /// guarantee that anything that the user will do to an object of type A can
2234 /// also be done to an object of type B. This is trivially true if the two
2235 /// types are the same, or if B is a subclass of A. It becomes more complex
2236 /// in cases where protocols are involved.
2237 ///
2238 /// Object types in Objective-C describe the minimum requirements for an
2239 /// object, rather than providing a complete description of a type. For
2240 /// example, if A is a subclass of B, then B* may refer to an instance of A.
2241 /// The principle of substitutability means that we may use an instance of A
2242 /// anywhere that we may use an instance of B - it will implement all of the
2243 /// ivars of B and all of the methods of B.
2244 ///
2245 /// This substitutability is important when type checking methods, because
2246 /// the implementation may have stricter type definitions than the interface.
2247 /// The interface specifies minimum requirements, but the implementation may
2248 /// have more accurate ones. For example, a method may privately accept
2249 /// instances of B, but only publish that it accepts instances of A. Any
2250 /// object passed to it will be type checked against B, and so will implicitly
2251 /// by a valid A*. Similarly, a method may return a subclass of the class that
2252 /// it is declared as returning.
2253 ///
2254 /// This is most important when considering subclassing. A method in a
2255 /// subclass must accept any object as an argument that its superclass's
2256 /// implementation accepts. It may, however, accept a more general type
2257 /// without breaking substitutability (i.e. you can still use the subclass
2258 /// anywhere that you can use the superclass, but not vice versa). The
2259 /// converse requirement applies to return types: the return type for a
2260 /// subclass method must be a valid object of the kind that the superclass
2261 /// advertises, but it may be specified more accurately. This avoids the need
2262 /// for explicit down-casting by callers.
2263 ///
2264 /// Note: This is a stricter requirement than for assignment.
isObjCTypeSubstitutable(ASTContext & Context,const ObjCObjectPointerType * A,const ObjCObjectPointerType * B,bool rejectId)2265 static bool isObjCTypeSubstitutable(ASTContext &Context,
2266 const ObjCObjectPointerType *A,
2267 const ObjCObjectPointerType *B,
2268 bool rejectId) {
2269 // Reject a protocol-unqualified id.
2270 if (rejectId && B->isObjCIdType()) return false;
2271
2272 // If B is a qualified id, then A must also be a qualified id and it must
2273 // implement all of the protocols in B. It may not be a qualified class.
2274 // For example, MyClass<A> can be assigned to id<A>, but MyClass<A> is a
2275 // stricter definition so it is not substitutable for id<A>.
2276 if (B->isObjCQualifiedIdType()) {
2277 return A->isObjCQualifiedIdType() &&
2278 Context.ObjCQualifiedIdTypesAreCompatible(A, B, false);
2279 }
2280
2281 /*
2282 // id is a special type that bypasses type checking completely. We want a
2283 // warning when it is used in one place but not another.
2284 if (C.isObjCIdType(A) || C.isObjCIdType(B)) return false;
2285
2286
2287 // If B is a qualified id, then A must also be a qualified id (which it isn't
2288 // if we've got this far)
2289 if (B->isObjCQualifiedIdType()) return false;
2290 */
2291
2292 // Now we know that A and B are (potentially-qualified) class types. The
2293 // normal rules for assignment apply.
2294 return Context.canAssignObjCInterfaces(A, B);
2295 }
2296
getTypeRange(TypeSourceInfo * TSI)2297 static SourceRange getTypeRange(TypeSourceInfo *TSI) {
2298 return (TSI ? TSI->getTypeLoc().getSourceRange() : SourceRange());
2299 }
2300
2301 /// Determine whether two set of Objective-C declaration qualifiers conflict.
objcModifiersConflict(Decl::ObjCDeclQualifier x,Decl::ObjCDeclQualifier y)2302 static bool objcModifiersConflict(Decl::ObjCDeclQualifier x,
2303 Decl::ObjCDeclQualifier y) {
2304 return (x & ~Decl::OBJC_TQ_CSNullability) !=
2305 (y & ~Decl::OBJC_TQ_CSNullability);
2306 }
2307
CheckMethodOverrideReturn(Sema & S,ObjCMethodDecl * MethodImpl,ObjCMethodDecl * MethodDecl,bool IsProtocolMethodDecl,bool IsOverridingMode,bool Warn)2308 static bool CheckMethodOverrideReturn(Sema &S,
2309 ObjCMethodDecl *MethodImpl,
2310 ObjCMethodDecl *MethodDecl,
2311 bool IsProtocolMethodDecl,
2312 bool IsOverridingMode,
2313 bool Warn) {
2314 if (IsProtocolMethodDecl &&
2315 objcModifiersConflict(MethodDecl->getObjCDeclQualifier(),
2316 MethodImpl->getObjCDeclQualifier())) {
2317 if (Warn) {
2318 S.Diag(MethodImpl->getLocation(),
2319 (IsOverridingMode
2320 ? diag::warn_conflicting_overriding_ret_type_modifiers
2321 : diag::warn_conflicting_ret_type_modifiers))
2322 << MethodImpl->getDeclName()
2323 << MethodImpl->getReturnTypeSourceRange();
2324 S.Diag(MethodDecl->getLocation(), diag::note_previous_declaration)
2325 << MethodDecl->getReturnTypeSourceRange();
2326 }
2327 else
2328 return false;
2329 }
2330 if (Warn && IsOverridingMode &&
2331 !isa<ObjCImplementationDecl>(MethodImpl->getDeclContext()) &&
2332 !S.Context.hasSameNullabilityTypeQualifier(MethodImpl->getReturnType(),
2333 MethodDecl->getReturnType(),
2334 false)) {
2335 auto nullabilityMethodImpl =
2336 *MethodImpl->getReturnType()->getNullability(S.Context);
2337 auto nullabilityMethodDecl =
2338 *MethodDecl->getReturnType()->getNullability(S.Context);
2339 S.Diag(MethodImpl->getLocation(),
2340 diag::warn_conflicting_nullability_attr_overriding_ret_types)
2341 << DiagNullabilityKind(
2342 nullabilityMethodImpl,
2343 ((MethodImpl->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2344 != 0))
2345 << DiagNullabilityKind(
2346 nullabilityMethodDecl,
2347 ((MethodDecl->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2348 != 0));
2349 S.Diag(MethodDecl->getLocation(), diag::note_previous_declaration);
2350 }
2351
2352 if (S.Context.hasSameUnqualifiedType(MethodImpl->getReturnType(),
2353 MethodDecl->getReturnType()))
2354 return true;
2355 if (!Warn)
2356 return false;
2357
2358 unsigned DiagID =
2359 IsOverridingMode ? diag::warn_conflicting_overriding_ret_types
2360 : diag::warn_conflicting_ret_types;
2361
2362 // Mismatches between ObjC pointers go into a different warning
2363 // category, and sometimes they're even completely explicitly allowed.
2364 if (const ObjCObjectPointerType *ImplPtrTy =
2365 MethodImpl->getReturnType()->getAs<ObjCObjectPointerType>()) {
2366 if (const ObjCObjectPointerType *IfacePtrTy =
2367 MethodDecl->getReturnType()->getAs<ObjCObjectPointerType>()) {
2368 // Allow non-matching return types as long as they don't violate
2369 // the principle of substitutability. Specifically, we permit
2370 // return types that are subclasses of the declared return type,
2371 // or that are more-qualified versions of the declared type.
2372 if (isObjCTypeSubstitutable(S.Context, IfacePtrTy, ImplPtrTy, false))
2373 return false;
2374
2375 DiagID =
2376 IsOverridingMode ? diag::warn_non_covariant_overriding_ret_types
2377 : diag::warn_non_covariant_ret_types;
2378 }
2379 }
2380
2381 S.Diag(MethodImpl->getLocation(), DiagID)
2382 << MethodImpl->getDeclName() << MethodDecl->getReturnType()
2383 << MethodImpl->getReturnType()
2384 << MethodImpl->getReturnTypeSourceRange();
2385 S.Diag(MethodDecl->getLocation(), IsOverridingMode
2386 ? diag::note_previous_declaration
2387 : diag::note_previous_definition)
2388 << MethodDecl->getReturnTypeSourceRange();
2389 return false;
2390 }
2391
CheckMethodOverrideParam(Sema & S,ObjCMethodDecl * MethodImpl,ObjCMethodDecl * MethodDecl,ParmVarDecl * ImplVar,ParmVarDecl * IfaceVar,bool IsProtocolMethodDecl,bool IsOverridingMode,bool Warn)2392 static bool CheckMethodOverrideParam(Sema &S,
2393 ObjCMethodDecl *MethodImpl,
2394 ObjCMethodDecl *MethodDecl,
2395 ParmVarDecl *ImplVar,
2396 ParmVarDecl *IfaceVar,
2397 bool IsProtocolMethodDecl,
2398 bool IsOverridingMode,
2399 bool Warn) {
2400 if (IsProtocolMethodDecl &&
2401 objcModifiersConflict(ImplVar->getObjCDeclQualifier(),
2402 IfaceVar->getObjCDeclQualifier())) {
2403 if (Warn) {
2404 if (IsOverridingMode)
2405 S.Diag(ImplVar->getLocation(),
2406 diag::warn_conflicting_overriding_param_modifiers)
2407 << getTypeRange(ImplVar->getTypeSourceInfo())
2408 << MethodImpl->getDeclName();
2409 else S.Diag(ImplVar->getLocation(),
2410 diag::warn_conflicting_param_modifiers)
2411 << getTypeRange(ImplVar->getTypeSourceInfo())
2412 << MethodImpl->getDeclName();
2413 S.Diag(IfaceVar->getLocation(), diag::note_previous_declaration)
2414 << getTypeRange(IfaceVar->getTypeSourceInfo());
2415 }
2416 else
2417 return false;
2418 }
2419
2420 QualType ImplTy = ImplVar->getType();
2421 QualType IfaceTy = IfaceVar->getType();
2422 if (Warn && IsOverridingMode &&
2423 !isa<ObjCImplementationDecl>(MethodImpl->getDeclContext()) &&
2424 !S.Context.hasSameNullabilityTypeQualifier(ImplTy, IfaceTy, true)) {
2425 S.Diag(ImplVar->getLocation(),
2426 diag::warn_conflicting_nullability_attr_overriding_param_types)
2427 << DiagNullabilityKind(
2428 *ImplTy->getNullability(S.Context),
2429 ((ImplVar->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2430 != 0))
2431 << DiagNullabilityKind(
2432 *IfaceTy->getNullability(S.Context),
2433 ((IfaceVar->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability)
2434 != 0));
2435 S.Diag(IfaceVar->getLocation(), diag::note_previous_declaration);
2436 }
2437 if (S.Context.hasSameUnqualifiedType(ImplTy, IfaceTy))
2438 return true;
2439
2440 if (!Warn)
2441 return false;
2442 unsigned DiagID =
2443 IsOverridingMode ? diag::warn_conflicting_overriding_param_types
2444 : diag::warn_conflicting_param_types;
2445
2446 // Mismatches between ObjC pointers go into a different warning
2447 // category, and sometimes they're even completely explicitly allowed..
2448 if (const ObjCObjectPointerType *ImplPtrTy =
2449 ImplTy->getAs<ObjCObjectPointerType>()) {
2450 if (const ObjCObjectPointerType *IfacePtrTy =
2451 IfaceTy->getAs<ObjCObjectPointerType>()) {
2452 // Allow non-matching argument types as long as they don't
2453 // violate the principle of substitutability. Specifically, the
2454 // implementation must accept any objects that the superclass
2455 // accepts, however it may also accept others.
2456 if (isObjCTypeSubstitutable(S.Context, ImplPtrTy, IfacePtrTy, true))
2457 return false;
2458
2459 DiagID =
2460 IsOverridingMode ? diag::warn_non_contravariant_overriding_param_types
2461 : diag::warn_non_contravariant_param_types;
2462 }
2463 }
2464
2465 S.Diag(ImplVar->getLocation(), DiagID)
2466 << getTypeRange(ImplVar->getTypeSourceInfo())
2467 << MethodImpl->getDeclName() << IfaceTy << ImplTy;
2468 S.Diag(IfaceVar->getLocation(),
2469 (IsOverridingMode ? diag::note_previous_declaration
2470 : diag::note_previous_definition))
2471 << getTypeRange(IfaceVar->getTypeSourceInfo());
2472 return false;
2473 }
2474
2475 /// In ARC, check whether the conventional meanings of the two methods
2476 /// match. If they don't, it's a hard error.
checkMethodFamilyMismatch(Sema & S,ObjCMethodDecl * impl,ObjCMethodDecl * decl)2477 static bool checkMethodFamilyMismatch(Sema &S, ObjCMethodDecl *impl,
2478 ObjCMethodDecl *decl) {
2479 ObjCMethodFamily implFamily = impl->getMethodFamily();
2480 ObjCMethodFamily declFamily = decl->getMethodFamily();
2481 if (implFamily == declFamily) return false;
2482
2483 // Since conventions are sorted by selector, the only possibility is
2484 // that the types differ enough to cause one selector or the other
2485 // to fall out of the family.
2486 assert(implFamily == OMF_None || declFamily == OMF_None);
2487
2488 // No further diagnostics required on invalid declarations.
2489 if (impl->isInvalidDecl() || decl->isInvalidDecl()) return true;
2490
2491 const ObjCMethodDecl *unmatched = impl;
2492 ObjCMethodFamily family = declFamily;
2493 unsigned errorID = diag::err_arc_lost_method_convention;
2494 unsigned noteID = diag::note_arc_lost_method_convention;
2495 if (declFamily == OMF_None) {
2496 unmatched = decl;
2497 family = implFamily;
2498 errorID = diag::err_arc_gained_method_convention;
2499 noteID = diag::note_arc_gained_method_convention;
2500 }
2501
2502 // Indexes into a %select clause in the diagnostic.
2503 enum FamilySelector {
2504 F_alloc, F_copy, F_mutableCopy = F_copy, F_init, F_new
2505 };
2506 FamilySelector familySelector = FamilySelector();
2507
2508 switch (family) {
2509 case OMF_None: llvm_unreachable("logic error, no method convention");
2510 case OMF_retain:
2511 case OMF_release:
2512 case OMF_autorelease:
2513 case OMF_dealloc:
2514 case OMF_finalize:
2515 case OMF_retainCount:
2516 case OMF_self:
2517 case OMF_initialize:
2518 case OMF_performSelector:
2519 // Mismatches for these methods don't change ownership
2520 // conventions, so we don't care.
2521 return false;
2522
2523 case OMF_init: familySelector = F_init; break;
2524 case OMF_alloc: familySelector = F_alloc; break;
2525 case OMF_copy: familySelector = F_copy; break;
2526 case OMF_mutableCopy: familySelector = F_mutableCopy; break;
2527 case OMF_new: familySelector = F_new; break;
2528 }
2529
2530 enum ReasonSelector { R_NonObjectReturn, R_UnrelatedReturn };
2531 ReasonSelector reasonSelector;
2532
2533 // The only reason these methods don't fall within their families is
2534 // due to unusual result types.
2535 if (unmatched->getReturnType()->isObjCObjectPointerType()) {
2536 reasonSelector = R_UnrelatedReturn;
2537 } else {
2538 reasonSelector = R_NonObjectReturn;
2539 }
2540
2541 S.Diag(impl->getLocation(), errorID) << int(familySelector) << int(reasonSelector);
2542 S.Diag(decl->getLocation(), noteID) << int(familySelector) << int(reasonSelector);
2543
2544 return true;
2545 }
2546
WarnConflictingTypedMethods(ObjCMethodDecl * ImpMethodDecl,ObjCMethodDecl * MethodDecl,bool IsProtocolMethodDecl)2547 void Sema::WarnConflictingTypedMethods(ObjCMethodDecl *ImpMethodDecl,
2548 ObjCMethodDecl *MethodDecl,
2549 bool IsProtocolMethodDecl) {
2550 if (getLangOpts().ObjCAutoRefCount &&
2551 checkMethodFamilyMismatch(*this, ImpMethodDecl, MethodDecl))
2552 return;
2553
2554 CheckMethodOverrideReturn(*this, ImpMethodDecl, MethodDecl,
2555 IsProtocolMethodDecl, false,
2556 true);
2557
2558 for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(),
2559 IF = MethodDecl->param_begin(), EM = ImpMethodDecl->param_end(),
2560 EF = MethodDecl->param_end();
2561 IM != EM && IF != EF; ++IM, ++IF) {
2562 CheckMethodOverrideParam(*this, ImpMethodDecl, MethodDecl, *IM, *IF,
2563 IsProtocolMethodDecl, false, true);
2564 }
2565
2566 if (ImpMethodDecl->isVariadic() != MethodDecl->isVariadic()) {
2567 Diag(ImpMethodDecl->getLocation(),
2568 diag::warn_conflicting_variadic);
2569 Diag(MethodDecl->getLocation(), diag::note_previous_declaration);
2570 }
2571 }
2572
CheckConflictingOverridingMethod(ObjCMethodDecl * Method,ObjCMethodDecl * Overridden,bool IsProtocolMethodDecl)2573 void Sema::CheckConflictingOverridingMethod(ObjCMethodDecl *Method,
2574 ObjCMethodDecl *Overridden,
2575 bool IsProtocolMethodDecl) {
2576
2577 CheckMethodOverrideReturn(*this, Method, Overridden,
2578 IsProtocolMethodDecl, true,
2579 true);
2580
2581 for (ObjCMethodDecl::param_iterator IM = Method->param_begin(),
2582 IF = Overridden->param_begin(), EM = Method->param_end(),
2583 EF = Overridden->param_end();
2584 IM != EM && IF != EF; ++IM, ++IF) {
2585 CheckMethodOverrideParam(*this, Method, Overridden, *IM, *IF,
2586 IsProtocolMethodDecl, true, true);
2587 }
2588
2589 if (Method->isVariadic() != Overridden->isVariadic()) {
2590 Diag(Method->getLocation(),
2591 diag::warn_conflicting_overriding_variadic);
2592 Diag(Overridden->getLocation(), diag::note_previous_declaration);
2593 }
2594 }
2595
2596 /// WarnExactTypedMethods - This routine issues a warning if method
2597 /// implementation declaration matches exactly that of its declaration.
WarnExactTypedMethods(ObjCMethodDecl * ImpMethodDecl,ObjCMethodDecl * MethodDecl,bool IsProtocolMethodDecl)2598 void Sema::WarnExactTypedMethods(ObjCMethodDecl *ImpMethodDecl,
2599 ObjCMethodDecl *MethodDecl,
2600 bool IsProtocolMethodDecl) {
2601 // don't issue warning when protocol method is optional because primary
2602 // class is not required to implement it and it is safe for protocol
2603 // to implement it.
2604 if (MethodDecl->getImplementationControl() == ObjCMethodDecl::Optional)
2605 return;
2606 // don't issue warning when primary class's method is
2607 // depecated/unavailable.
2608 if (MethodDecl->hasAttr<UnavailableAttr>() ||
2609 MethodDecl->hasAttr<DeprecatedAttr>())
2610 return;
2611
2612 bool match = CheckMethodOverrideReturn(*this, ImpMethodDecl, MethodDecl,
2613 IsProtocolMethodDecl, false, false);
2614 if (match)
2615 for (ObjCMethodDecl::param_iterator IM = ImpMethodDecl->param_begin(),
2616 IF = MethodDecl->param_begin(), EM = ImpMethodDecl->param_end(),
2617 EF = MethodDecl->param_end();
2618 IM != EM && IF != EF; ++IM, ++IF) {
2619 match = CheckMethodOverrideParam(*this, ImpMethodDecl, MethodDecl,
2620 *IM, *IF,
2621 IsProtocolMethodDecl, false, false);
2622 if (!match)
2623 break;
2624 }
2625 if (match)
2626 match = (ImpMethodDecl->isVariadic() == MethodDecl->isVariadic());
2627 if (match)
2628 match = !(MethodDecl->isClassMethod() &&
2629 MethodDecl->getSelector() == GetNullarySelector("load", Context));
2630
2631 if (match) {
2632 Diag(ImpMethodDecl->getLocation(),
2633 diag::warn_category_method_impl_match);
2634 Diag(MethodDecl->getLocation(), diag::note_method_declared_at)
2635 << MethodDecl->getDeclName();
2636 }
2637 }
2638
2639 /// FIXME: Type hierarchies in Objective-C can be deep. We could most likely
2640 /// improve the efficiency of selector lookups and type checking by associating
2641 /// with each protocol / interface / category the flattened instance tables. If
2642 /// we used an immutable set to keep the table then it wouldn't add significant
2643 /// memory cost and it would be handy for lookups.
2644
2645 typedef llvm::DenseSet<IdentifierInfo*> ProtocolNameSet;
2646 typedef std::unique_ptr<ProtocolNameSet> LazyProtocolNameSet;
2647
findProtocolsWithExplicitImpls(const ObjCProtocolDecl * PDecl,ProtocolNameSet & PNS)2648 static void findProtocolsWithExplicitImpls(const ObjCProtocolDecl *PDecl,
2649 ProtocolNameSet &PNS) {
2650 if (PDecl->hasAttr<ObjCExplicitProtocolImplAttr>())
2651 PNS.insert(PDecl->getIdentifier());
2652 for (const auto *PI : PDecl->protocols())
2653 findProtocolsWithExplicitImpls(PI, PNS);
2654 }
2655
2656 /// Recursively populates a set with all conformed protocols in a class
2657 /// hierarchy that have the 'objc_protocol_requires_explicit_implementation'
2658 /// attribute.
findProtocolsWithExplicitImpls(const ObjCInterfaceDecl * Super,ProtocolNameSet & PNS)2659 static void findProtocolsWithExplicitImpls(const ObjCInterfaceDecl *Super,
2660 ProtocolNameSet &PNS) {
2661 if (!Super)
2662 return;
2663
2664 for (const auto *I : Super->all_referenced_protocols())
2665 findProtocolsWithExplicitImpls(I, PNS);
2666
2667 findProtocolsWithExplicitImpls(Super->getSuperClass(), PNS);
2668 }
2669
2670 /// CheckProtocolMethodDefs - This routine checks unimplemented methods
2671 /// Declared in protocol, and those referenced by it.
CheckProtocolMethodDefs(Sema & S,SourceLocation ImpLoc,ObjCProtocolDecl * PDecl,bool & IncompleteImpl,const Sema::SelectorSet & InsMap,const Sema::SelectorSet & ClsMap,ObjCContainerDecl * CDecl,LazyProtocolNameSet & ProtocolsExplictImpl)2672 static void CheckProtocolMethodDefs(Sema &S,
2673 SourceLocation ImpLoc,
2674 ObjCProtocolDecl *PDecl,
2675 bool& IncompleteImpl,
2676 const Sema::SelectorSet &InsMap,
2677 const Sema::SelectorSet &ClsMap,
2678 ObjCContainerDecl *CDecl,
2679 LazyProtocolNameSet &ProtocolsExplictImpl) {
2680 ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(CDecl);
2681 ObjCInterfaceDecl *IDecl = C ? C->getClassInterface()
2682 : dyn_cast<ObjCInterfaceDecl>(CDecl);
2683 assert (IDecl && "CheckProtocolMethodDefs - IDecl is null");
2684
2685 ObjCInterfaceDecl *Super = IDecl->getSuperClass();
2686 ObjCInterfaceDecl *NSIDecl = nullptr;
2687
2688 // If this protocol is marked 'objc_protocol_requires_explicit_implementation'
2689 // then we should check if any class in the super class hierarchy also
2690 // conforms to this protocol, either directly or via protocol inheritance.
2691 // If so, we can skip checking this protocol completely because we
2692 // know that a parent class already satisfies this protocol.
2693 //
2694 // Note: we could generalize this logic for all protocols, and merely
2695 // add the limit on looking at the super class chain for just
2696 // specially marked protocols. This may be a good optimization. This
2697 // change is restricted to 'objc_protocol_requires_explicit_implementation'
2698 // protocols for now for controlled evaluation.
2699 if (PDecl->hasAttr<ObjCExplicitProtocolImplAttr>()) {
2700 if (!ProtocolsExplictImpl) {
2701 ProtocolsExplictImpl.reset(new ProtocolNameSet);
2702 findProtocolsWithExplicitImpls(Super, *ProtocolsExplictImpl);
2703 }
2704 if (ProtocolsExplictImpl->find(PDecl->getIdentifier()) !=
2705 ProtocolsExplictImpl->end())
2706 return;
2707
2708 // If no super class conforms to the protocol, we should not search
2709 // for methods in the super class to implicitly satisfy the protocol.
2710 Super = nullptr;
2711 }
2712
2713 if (S.getLangOpts().ObjCRuntime.isNeXTFamily()) {
2714 // check to see if class implements forwardInvocation method and objects
2715 // of this class are derived from 'NSProxy' so that to forward requests
2716 // from one object to another.
2717 // Under such conditions, which means that every method possible is
2718 // implemented in the class, we should not issue "Method definition not
2719 // found" warnings.
2720 // FIXME: Use a general GetUnarySelector method for this.
2721 IdentifierInfo* II = &S.Context.Idents.get("forwardInvocation");
2722 Selector fISelector = S.Context.Selectors.getSelector(1, &II);
2723 if (InsMap.count(fISelector))
2724 // Is IDecl derived from 'NSProxy'? If so, no instance methods
2725 // need be implemented in the implementation.
2726 NSIDecl = IDecl->lookupInheritedClass(&S.Context.Idents.get("NSProxy"));
2727 }
2728
2729 // If this is a forward protocol declaration, get its definition.
2730 if (!PDecl->isThisDeclarationADefinition() &&
2731 PDecl->getDefinition())
2732 PDecl = PDecl->getDefinition();
2733
2734 // If a method lookup fails locally we still need to look and see if
2735 // the method was implemented by a base class or an inherited
2736 // protocol. This lookup is slow, but occurs rarely in correct code
2737 // and otherwise would terminate in a warning.
2738
2739 // check unimplemented instance methods.
2740 if (!NSIDecl)
2741 for (auto *method : PDecl->instance_methods()) {
2742 if (method->getImplementationControl() != ObjCMethodDecl::Optional &&
2743 !method->isPropertyAccessor() &&
2744 !InsMap.count(method->getSelector()) &&
2745 (!Super || !Super->lookupMethod(method->getSelector(),
2746 true /* instance */,
2747 false /* shallowCategory */,
2748 true /* followsSuper */,
2749 nullptr /* category */))) {
2750 // If a method is not implemented in the category implementation but
2751 // has been declared in its primary class, superclass,
2752 // or in one of their protocols, no need to issue the warning.
2753 // This is because method will be implemented in the primary class
2754 // or one of its super class implementation.
2755
2756 // Ugly, but necessary. Method declared in protocol might have
2757 // have been synthesized due to a property declared in the class which
2758 // uses the protocol.
2759 if (ObjCMethodDecl *MethodInClass =
2760 IDecl->lookupMethod(method->getSelector(),
2761 true /* instance */,
2762 true /* shallowCategoryLookup */,
2763 false /* followSuper */))
2764 if (C || MethodInClass->isPropertyAccessor())
2765 continue;
2766 unsigned DIAG = diag::warn_unimplemented_protocol_method;
2767 if (!S.Diags.isIgnored(DIAG, ImpLoc)) {
2768 WarnUndefinedMethod(S, ImpLoc, method, IncompleteImpl, DIAG,
2769 PDecl);
2770 }
2771 }
2772 }
2773 // check unimplemented class methods
2774 for (auto *method : PDecl->class_methods()) {
2775 if (method->getImplementationControl() != ObjCMethodDecl::Optional &&
2776 !ClsMap.count(method->getSelector()) &&
2777 (!Super || !Super->lookupMethod(method->getSelector(),
2778 false /* class method */,
2779 false /* shallowCategoryLookup */,
2780 true /* followSuper */,
2781 nullptr /* category */))) {
2782 // See above comment for instance method lookups.
2783 if (C && IDecl->lookupMethod(method->getSelector(),
2784 false /* class */,
2785 true /* shallowCategoryLookup */,
2786 false /* followSuper */))
2787 continue;
2788
2789 unsigned DIAG = diag::warn_unimplemented_protocol_method;
2790 if (!S.Diags.isIgnored(DIAG, ImpLoc)) {
2791 WarnUndefinedMethod(S, ImpLoc, method, IncompleteImpl, DIAG, PDecl);
2792 }
2793 }
2794 }
2795 // Check on this protocols's referenced protocols, recursively.
2796 for (auto *PI : PDecl->protocols())
2797 CheckProtocolMethodDefs(S, ImpLoc, PI, IncompleteImpl, InsMap, ClsMap,
2798 CDecl, ProtocolsExplictImpl);
2799 }
2800
2801 /// MatchAllMethodDeclarations - Check methods declared in interface
2802 /// or protocol against those declared in their implementations.
2803 ///
MatchAllMethodDeclarations(const SelectorSet & InsMap,const SelectorSet & ClsMap,SelectorSet & InsMapSeen,SelectorSet & ClsMapSeen,ObjCImplDecl * IMPDecl,ObjCContainerDecl * CDecl,bool & IncompleteImpl,bool ImmediateClass,bool WarnCategoryMethodImpl)2804 void Sema::MatchAllMethodDeclarations(const SelectorSet &InsMap,
2805 const SelectorSet &ClsMap,
2806 SelectorSet &InsMapSeen,
2807 SelectorSet &ClsMapSeen,
2808 ObjCImplDecl* IMPDecl,
2809 ObjCContainerDecl* CDecl,
2810 bool &IncompleteImpl,
2811 bool ImmediateClass,
2812 bool WarnCategoryMethodImpl) {
2813 // Check and see if instance methods in class interface have been
2814 // implemented in the implementation class. If so, their types match.
2815 for (auto *I : CDecl->instance_methods()) {
2816 if (!InsMapSeen.insert(I->getSelector()).second)
2817 continue;
2818 if (!I->isPropertyAccessor() &&
2819 !InsMap.count(I->getSelector())) {
2820 if (ImmediateClass)
2821 WarnUndefinedMethod(*this, IMPDecl->getLocation(), I, IncompleteImpl,
2822 diag::warn_undef_method_impl);
2823 continue;
2824 } else {
2825 ObjCMethodDecl *ImpMethodDecl =
2826 IMPDecl->getInstanceMethod(I->getSelector());
2827 assert(CDecl->getInstanceMethod(I->getSelector(), true/*AllowHidden*/) &&
2828 "Expected to find the method through lookup as well");
2829 // ImpMethodDecl may be null as in a @dynamic property.
2830 if (ImpMethodDecl) {
2831 // Skip property accessor function stubs.
2832 if (ImpMethodDecl->isSynthesizedAccessorStub())
2833 continue;
2834 if (!WarnCategoryMethodImpl)
2835 WarnConflictingTypedMethods(ImpMethodDecl, I,
2836 isa<ObjCProtocolDecl>(CDecl));
2837 else if (!I->isPropertyAccessor())
2838 WarnExactTypedMethods(ImpMethodDecl, I, isa<ObjCProtocolDecl>(CDecl));
2839 }
2840 }
2841 }
2842
2843 // Check and see if class methods in class interface have been
2844 // implemented in the implementation class. If so, their types match.
2845 for (auto *I : CDecl->class_methods()) {
2846 if (!ClsMapSeen.insert(I->getSelector()).second)
2847 continue;
2848 if (!I->isPropertyAccessor() &&
2849 !ClsMap.count(I->getSelector())) {
2850 if (ImmediateClass)
2851 WarnUndefinedMethod(*this, IMPDecl->getLocation(), I, IncompleteImpl,
2852 diag::warn_undef_method_impl);
2853 } else {
2854 ObjCMethodDecl *ImpMethodDecl =
2855 IMPDecl->getClassMethod(I->getSelector());
2856 assert(CDecl->getClassMethod(I->getSelector(), true/*AllowHidden*/) &&
2857 "Expected to find the method through lookup as well");
2858 // ImpMethodDecl may be null as in a @dynamic property.
2859 if (ImpMethodDecl) {
2860 // Skip property accessor function stubs.
2861 if (ImpMethodDecl->isSynthesizedAccessorStub())
2862 continue;
2863 if (!WarnCategoryMethodImpl)
2864 WarnConflictingTypedMethods(ImpMethodDecl, I,
2865 isa<ObjCProtocolDecl>(CDecl));
2866 else if (!I->isPropertyAccessor())
2867 WarnExactTypedMethods(ImpMethodDecl, I, isa<ObjCProtocolDecl>(CDecl));
2868 }
2869 }
2870 }
2871
2872 if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl> (CDecl)) {
2873 // Also, check for methods declared in protocols inherited by
2874 // this protocol.
2875 for (auto *PI : PD->protocols())
2876 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2877 IMPDecl, PI, IncompleteImpl, false,
2878 WarnCategoryMethodImpl);
2879 }
2880
2881 if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl> (CDecl)) {
2882 // when checking that methods in implementation match their declaration,
2883 // i.e. when WarnCategoryMethodImpl is false, check declarations in class
2884 // extension; as well as those in categories.
2885 if (!WarnCategoryMethodImpl) {
2886 for (auto *Cat : I->visible_categories())
2887 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2888 IMPDecl, Cat, IncompleteImpl,
2889 ImmediateClass && Cat->IsClassExtension(),
2890 WarnCategoryMethodImpl);
2891 } else {
2892 // Also methods in class extensions need be looked at next.
2893 for (auto *Ext : I->visible_extensions())
2894 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2895 IMPDecl, Ext, IncompleteImpl, false,
2896 WarnCategoryMethodImpl);
2897 }
2898
2899 // Check for any implementation of a methods declared in protocol.
2900 for (auto *PI : I->all_referenced_protocols())
2901 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2902 IMPDecl, PI, IncompleteImpl, false,
2903 WarnCategoryMethodImpl);
2904
2905 // FIXME. For now, we are not checking for exact match of methods
2906 // in category implementation and its primary class's super class.
2907 if (!WarnCategoryMethodImpl && I->getSuperClass())
2908 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2909 IMPDecl,
2910 I->getSuperClass(), IncompleteImpl, false);
2911 }
2912 }
2913
2914 /// CheckCategoryVsClassMethodMatches - Checks that methods implemented in
2915 /// category matches with those implemented in its primary class and
2916 /// warns each time an exact match is found.
CheckCategoryVsClassMethodMatches(ObjCCategoryImplDecl * CatIMPDecl)2917 void Sema::CheckCategoryVsClassMethodMatches(
2918 ObjCCategoryImplDecl *CatIMPDecl) {
2919 // Get category's primary class.
2920 ObjCCategoryDecl *CatDecl = CatIMPDecl->getCategoryDecl();
2921 if (!CatDecl)
2922 return;
2923 ObjCInterfaceDecl *IDecl = CatDecl->getClassInterface();
2924 if (!IDecl)
2925 return;
2926 ObjCInterfaceDecl *SuperIDecl = IDecl->getSuperClass();
2927 SelectorSet InsMap, ClsMap;
2928
2929 for (const auto *I : CatIMPDecl->instance_methods()) {
2930 Selector Sel = I->getSelector();
2931 // When checking for methods implemented in the category, skip over
2932 // those declared in category class's super class. This is because
2933 // the super class must implement the method.
2934 if (SuperIDecl && SuperIDecl->lookupMethod(Sel, true))
2935 continue;
2936 InsMap.insert(Sel);
2937 }
2938
2939 for (const auto *I : CatIMPDecl->class_methods()) {
2940 Selector Sel = I->getSelector();
2941 if (SuperIDecl && SuperIDecl->lookupMethod(Sel, false))
2942 continue;
2943 ClsMap.insert(Sel);
2944 }
2945 if (InsMap.empty() && ClsMap.empty())
2946 return;
2947
2948 SelectorSet InsMapSeen, ClsMapSeen;
2949 bool IncompleteImpl = false;
2950 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
2951 CatIMPDecl, IDecl,
2952 IncompleteImpl, false,
2953 true /*WarnCategoryMethodImpl*/);
2954 }
2955
ImplMethodsVsClassMethods(Scope * S,ObjCImplDecl * IMPDecl,ObjCContainerDecl * CDecl,bool IncompleteImpl)2956 void Sema::ImplMethodsVsClassMethods(Scope *S, ObjCImplDecl* IMPDecl,
2957 ObjCContainerDecl* CDecl,
2958 bool IncompleteImpl) {
2959 SelectorSet InsMap;
2960 // Check and see if instance methods in class interface have been
2961 // implemented in the implementation class.
2962 for (const auto *I : IMPDecl->instance_methods())
2963 InsMap.insert(I->getSelector());
2964
2965 // Add the selectors for getters/setters of @dynamic properties.
2966 for (const auto *PImpl : IMPDecl->property_impls()) {
2967 // We only care about @dynamic implementations.
2968 if (PImpl->getPropertyImplementation() != ObjCPropertyImplDecl::Dynamic)
2969 continue;
2970
2971 const auto *P = PImpl->getPropertyDecl();
2972 if (!P) continue;
2973
2974 InsMap.insert(P->getGetterName());
2975 if (!P->getSetterName().isNull())
2976 InsMap.insert(P->getSetterName());
2977 }
2978
2979 // Check and see if properties declared in the interface have either 1)
2980 // an implementation or 2) there is a @synthesize/@dynamic implementation
2981 // of the property in the @implementation.
2982 if (const ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(CDecl)) {
2983 bool SynthesizeProperties = LangOpts.ObjCDefaultSynthProperties &&
2984 LangOpts.ObjCRuntime.isNonFragile() &&
2985 !IDecl->isObjCRequiresPropertyDefs();
2986 DiagnoseUnimplementedProperties(S, IMPDecl, CDecl, SynthesizeProperties);
2987 }
2988
2989 // Diagnose null-resettable synthesized setters.
2990 diagnoseNullResettableSynthesizedSetters(IMPDecl);
2991
2992 SelectorSet ClsMap;
2993 for (const auto *I : IMPDecl->class_methods())
2994 ClsMap.insert(I->getSelector());
2995
2996 // Check for type conflict of methods declared in a class/protocol and
2997 // its implementation; if any.
2998 SelectorSet InsMapSeen, ClsMapSeen;
2999 MatchAllMethodDeclarations(InsMap, ClsMap, InsMapSeen, ClsMapSeen,
3000 IMPDecl, CDecl,
3001 IncompleteImpl, true);
3002
3003 // check all methods implemented in category against those declared
3004 // in its primary class.
3005 if (ObjCCategoryImplDecl *CatDecl =
3006 dyn_cast<ObjCCategoryImplDecl>(IMPDecl))
3007 CheckCategoryVsClassMethodMatches(CatDecl);
3008
3009 // Check the protocol list for unimplemented methods in the @implementation
3010 // class.
3011 // Check and see if class methods in class interface have been
3012 // implemented in the implementation class.
3013
3014 LazyProtocolNameSet ExplicitImplProtocols;
3015
3016 if (ObjCInterfaceDecl *I = dyn_cast<ObjCInterfaceDecl> (CDecl)) {
3017 for (auto *PI : I->all_referenced_protocols())
3018 CheckProtocolMethodDefs(*this, IMPDecl->getLocation(), PI, IncompleteImpl,
3019 InsMap, ClsMap, I, ExplicitImplProtocols);
3020 } else if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(CDecl)) {
3021 // For extended class, unimplemented methods in its protocols will
3022 // be reported in the primary class.
3023 if (!C->IsClassExtension()) {
3024 for (auto *P : C->protocols())
3025 CheckProtocolMethodDefs(*this, IMPDecl->getLocation(), P,
3026 IncompleteImpl, InsMap, ClsMap, CDecl,
3027 ExplicitImplProtocols);
3028 DiagnoseUnimplementedProperties(S, IMPDecl, CDecl,
3029 /*SynthesizeProperties=*/false);
3030 }
3031 } else
3032 llvm_unreachable("invalid ObjCContainerDecl type.");
3033 }
3034
3035 Sema::DeclGroupPtrTy
ActOnForwardClassDeclaration(SourceLocation AtClassLoc,IdentifierInfo ** IdentList,SourceLocation * IdentLocs,ArrayRef<ObjCTypeParamList * > TypeParamLists,unsigned NumElts)3036 Sema::ActOnForwardClassDeclaration(SourceLocation AtClassLoc,
3037 IdentifierInfo **IdentList,
3038 SourceLocation *IdentLocs,
3039 ArrayRef<ObjCTypeParamList *> TypeParamLists,
3040 unsigned NumElts) {
3041 SmallVector<Decl *, 8> DeclsInGroup;
3042 for (unsigned i = 0; i != NumElts; ++i) {
3043 // Check for another declaration kind with the same name.
3044 NamedDecl *PrevDecl
3045 = LookupSingleName(TUScope, IdentList[i], IdentLocs[i],
3046 LookupOrdinaryName, forRedeclarationInCurContext());
3047 if (PrevDecl && !isa<ObjCInterfaceDecl>(PrevDecl)) {
3048 // GCC apparently allows the following idiom:
3049 //
3050 // typedef NSObject < XCElementTogglerP > XCElementToggler;
3051 // @class XCElementToggler;
3052 //
3053 // Here we have chosen to ignore the forward class declaration
3054 // with a warning. Since this is the implied behavior.
3055 TypedefNameDecl *TDD = dyn_cast<TypedefNameDecl>(PrevDecl);
3056 if (!TDD || !TDD->getUnderlyingType()->isObjCObjectType()) {
3057 Diag(AtClassLoc, diag::err_redefinition_different_kind) << IdentList[i];
3058 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
3059 } else {
3060 // a forward class declaration matching a typedef name of a class refers
3061 // to the underlying class. Just ignore the forward class with a warning
3062 // as this will force the intended behavior which is to lookup the
3063 // typedef name.
3064 if (isa<ObjCObjectType>(TDD->getUnderlyingType())) {
3065 Diag(AtClassLoc, diag::warn_forward_class_redefinition)
3066 << IdentList[i];
3067 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
3068 continue;
3069 }
3070 }
3071 }
3072
3073 // Create a declaration to describe this forward declaration.
3074 ObjCInterfaceDecl *PrevIDecl
3075 = dyn_cast_or_null<ObjCInterfaceDecl>(PrevDecl);
3076
3077 IdentifierInfo *ClassName = IdentList[i];
3078 if (PrevIDecl && PrevIDecl->getIdentifier() != ClassName) {
3079 // A previous decl with a different name is because of
3080 // @compatibility_alias, for example:
3081 // \code
3082 // @class NewImage;
3083 // @compatibility_alias OldImage NewImage;
3084 // \endcode
3085 // A lookup for 'OldImage' will return the 'NewImage' decl.
3086 //
3087 // In such a case use the real declaration name, instead of the alias one,
3088 // otherwise we will break IdentifierResolver and redecls-chain invariants.
3089 // FIXME: If necessary, add a bit to indicate that this ObjCInterfaceDecl
3090 // has been aliased.
3091 ClassName = PrevIDecl->getIdentifier();
3092 }
3093
3094 // If this forward declaration has type parameters, compare them with the
3095 // type parameters of the previous declaration.
3096 ObjCTypeParamList *TypeParams = TypeParamLists[i];
3097 if (PrevIDecl && TypeParams) {
3098 if (ObjCTypeParamList *PrevTypeParams = PrevIDecl->getTypeParamList()) {
3099 // Check for consistency with the previous declaration.
3100 if (checkTypeParamListConsistency(
3101 *this, PrevTypeParams, TypeParams,
3102 TypeParamListContext::ForwardDeclaration)) {
3103 TypeParams = nullptr;
3104 }
3105 } else if (ObjCInterfaceDecl *Def = PrevIDecl->getDefinition()) {
3106 // The @interface does not have type parameters. Complain.
3107 Diag(IdentLocs[i], diag::err_objc_parameterized_forward_class)
3108 << ClassName
3109 << TypeParams->getSourceRange();
3110 Diag(Def->getLocation(), diag::note_defined_here)
3111 << ClassName;
3112
3113 TypeParams = nullptr;
3114 }
3115 }
3116
3117 ObjCInterfaceDecl *IDecl
3118 = ObjCInterfaceDecl::Create(Context, CurContext, AtClassLoc,
3119 ClassName, TypeParams, PrevIDecl,
3120 IdentLocs[i]);
3121 IDecl->setAtEndRange(IdentLocs[i]);
3122
3123 PushOnScopeChains(IDecl, TUScope);
3124 CheckObjCDeclScope(IDecl);
3125 DeclsInGroup.push_back(IDecl);
3126 }
3127
3128 return BuildDeclaratorGroup(DeclsInGroup);
3129 }
3130
3131 static bool tryMatchRecordTypes(ASTContext &Context,
3132 Sema::MethodMatchStrategy strategy,
3133 const Type *left, const Type *right);
3134
matchTypes(ASTContext & Context,Sema::MethodMatchStrategy strategy,QualType leftQT,QualType rightQT)3135 static bool matchTypes(ASTContext &Context, Sema::MethodMatchStrategy strategy,
3136 QualType leftQT, QualType rightQT) {
3137 const Type *left =
3138 Context.getCanonicalType(leftQT).getUnqualifiedType().getTypePtr();
3139 const Type *right =
3140 Context.getCanonicalType(rightQT).getUnqualifiedType().getTypePtr();
3141
3142 if (left == right) return true;
3143
3144 // If we're doing a strict match, the types have to match exactly.
3145 if (strategy == Sema::MMS_strict) return false;
3146
3147 if (left->isIncompleteType() || right->isIncompleteType()) return false;
3148
3149 // Otherwise, use this absurdly complicated algorithm to try to
3150 // validate the basic, low-level compatibility of the two types.
3151
3152 // As a minimum, require the sizes and alignments to match.
3153 TypeInfo LeftTI = Context.getTypeInfo(left);
3154 TypeInfo RightTI = Context.getTypeInfo(right);
3155 if (LeftTI.Width != RightTI.Width)
3156 return false;
3157
3158 if (LeftTI.Align != RightTI.Align)
3159 return false;
3160
3161 // Consider all the kinds of non-dependent canonical types:
3162 // - functions and arrays aren't possible as return and parameter types
3163
3164 // - vector types of equal size can be arbitrarily mixed
3165 if (isa<VectorType>(left)) return isa<VectorType>(right);
3166 if (isa<VectorType>(right)) return false;
3167
3168 // - references should only match references of identical type
3169 // - structs, unions, and Objective-C objects must match more-or-less
3170 // exactly
3171 // - everything else should be a scalar
3172 if (!left->isScalarType() || !right->isScalarType())
3173 return tryMatchRecordTypes(Context, strategy, left, right);
3174
3175 // Make scalars agree in kind, except count bools as chars, and group
3176 // all non-member pointers together.
3177 Type::ScalarTypeKind leftSK = left->getScalarTypeKind();
3178 Type::ScalarTypeKind rightSK = right->getScalarTypeKind();
3179 if (leftSK == Type::STK_Bool) leftSK = Type::STK_Integral;
3180 if (rightSK == Type::STK_Bool) rightSK = Type::STK_Integral;
3181 if (leftSK == Type::STK_CPointer || leftSK == Type::STK_BlockPointer)
3182 leftSK = Type::STK_ObjCObjectPointer;
3183 if (rightSK == Type::STK_CPointer || rightSK == Type::STK_BlockPointer)
3184 rightSK = Type::STK_ObjCObjectPointer;
3185
3186 // Note that data member pointers and function member pointers don't
3187 // intermix because of the size differences.
3188
3189 return (leftSK == rightSK);
3190 }
3191
tryMatchRecordTypes(ASTContext & Context,Sema::MethodMatchStrategy strategy,const Type * lt,const Type * rt)3192 static bool tryMatchRecordTypes(ASTContext &Context,
3193 Sema::MethodMatchStrategy strategy,
3194 const Type *lt, const Type *rt) {
3195 assert(lt && rt && lt != rt);
3196
3197 if (!isa<RecordType>(lt) || !isa<RecordType>(rt)) return false;
3198 RecordDecl *left = cast<RecordType>(lt)->getDecl();
3199 RecordDecl *right = cast<RecordType>(rt)->getDecl();
3200
3201 // Require union-hood to match.
3202 if (left->isUnion() != right->isUnion()) return false;
3203
3204 // Require an exact match if either is non-POD.
3205 if ((isa<CXXRecordDecl>(left) && !cast<CXXRecordDecl>(left)->isPOD()) ||
3206 (isa<CXXRecordDecl>(right) && !cast<CXXRecordDecl>(right)->isPOD()))
3207 return false;
3208
3209 // Require size and alignment to match.
3210 TypeInfo LeftTI = Context.getTypeInfo(lt);
3211 TypeInfo RightTI = Context.getTypeInfo(rt);
3212 if (LeftTI.Width != RightTI.Width)
3213 return false;
3214
3215 if (LeftTI.Align != RightTI.Align)
3216 return false;
3217
3218 // Require fields to match.
3219 RecordDecl::field_iterator li = left->field_begin(), le = left->field_end();
3220 RecordDecl::field_iterator ri = right->field_begin(), re = right->field_end();
3221 for (; li != le && ri != re; ++li, ++ri) {
3222 if (!matchTypes(Context, strategy, li->getType(), ri->getType()))
3223 return false;
3224 }
3225 return (li == le && ri == re);
3226 }
3227
3228 /// MatchTwoMethodDeclarations - Checks that two methods have matching type and
3229 /// returns true, or false, accordingly.
3230 /// TODO: Handle protocol list; such as id<p1,p2> in type comparisons
MatchTwoMethodDeclarations(const ObjCMethodDecl * left,const ObjCMethodDecl * right,MethodMatchStrategy strategy)3231 bool Sema::MatchTwoMethodDeclarations(const ObjCMethodDecl *left,
3232 const ObjCMethodDecl *right,
3233 MethodMatchStrategy strategy) {
3234 if (!matchTypes(Context, strategy, left->getReturnType(),
3235 right->getReturnType()))
3236 return false;
3237
3238 // If either is hidden, it is not considered to match.
3239 if (!left->isUnconditionallyVisible() || !right->isUnconditionallyVisible())
3240 return false;
3241
3242 if (left->isDirectMethod() != right->isDirectMethod())
3243 return false;
3244
3245 if (getLangOpts().ObjCAutoRefCount &&
3246 (left->hasAttr<NSReturnsRetainedAttr>()
3247 != right->hasAttr<NSReturnsRetainedAttr>() ||
3248 left->hasAttr<NSConsumesSelfAttr>()
3249 != right->hasAttr<NSConsumesSelfAttr>()))
3250 return false;
3251
3252 ObjCMethodDecl::param_const_iterator
3253 li = left->param_begin(), le = left->param_end(), ri = right->param_begin(),
3254 re = right->param_end();
3255
3256 for (; li != le && ri != re; ++li, ++ri) {
3257 assert(ri != right->param_end() && "Param mismatch");
3258 const ParmVarDecl *lparm = *li, *rparm = *ri;
3259
3260 if (!matchTypes(Context, strategy, lparm->getType(), rparm->getType()))
3261 return false;
3262
3263 if (getLangOpts().ObjCAutoRefCount &&
3264 lparm->hasAttr<NSConsumedAttr>() != rparm->hasAttr<NSConsumedAttr>())
3265 return false;
3266 }
3267 return true;
3268 }
3269
isMethodContextSameForKindofLookup(ObjCMethodDecl * Method,ObjCMethodDecl * MethodInList)3270 static bool isMethodContextSameForKindofLookup(ObjCMethodDecl *Method,
3271 ObjCMethodDecl *MethodInList) {
3272 auto *MethodProtocol = dyn_cast<ObjCProtocolDecl>(Method->getDeclContext());
3273 auto *MethodInListProtocol =
3274 dyn_cast<ObjCProtocolDecl>(MethodInList->getDeclContext());
3275 // If this method belongs to a protocol but the method in list does not, or
3276 // vice versa, we say the context is not the same.
3277 if ((MethodProtocol && !MethodInListProtocol) ||
3278 (!MethodProtocol && MethodInListProtocol))
3279 return false;
3280
3281 if (MethodProtocol && MethodInListProtocol)
3282 return true;
3283
3284 ObjCInterfaceDecl *MethodInterface = Method->getClassInterface();
3285 ObjCInterfaceDecl *MethodInListInterface =
3286 MethodInList->getClassInterface();
3287 return MethodInterface == MethodInListInterface;
3288 }
3289
addMethodToGlobalList(ObjCMethodList * List,ObjCMethodDecl * Method)3290 void Sema::addMethodToGlobalList(ObjCMethodList *List,
3291 ObjCMethodDecl *Method) {
3292 // Record at the head of the list whether there were 0, 1, or >= 2 methods
3293 // inside categories.
3294 if (ObjCCategoryDecl *CD =
3295 dyn_cast<ObjCCategoryDecl>(Method->getDeclContext()))
3296 if (!CD->IsClassExtension() && List->getBits() < 2)
3297 List->setBits(List->getBits() + 1);
3298
3299 // If the list is empty, make it a singleton list.
3300 if (List->getMethod() == nullptr) {
3301 List->setMethod(Method);
3302 List->setNext(nullptr);
3303 return;
3304 }
3305
3306 // We've seen a method with this name, see if we have already seen this type
3307 // signature.
3308 ObjCMethodList *Previous = List;
3309 ObjCMethodList *ListWithSameDeclaration = nullptr;
3310 for (; List; Previous = List, List = List->getNext()) {
3311 // If we are building a module, keep all of the methods.
3312 if (getLangOpts().isCompilingModule())
3313 continue;
3314
3315 bool SameDeclaration = MatchTwoMethodDeclarations(Method,
3316 List->getMethod());
3317 // Looking for method with a type bound requires the correct context exists.
3318 // We need to insert a method into the list if the context is different.
3319 // If the method's declaration matches the list
3320 // a> the method belongs to a different context: we need to insert it, in
3321 // order to emit the availability message, we need to prioritize over
3322 // availability among the methods with the same declaration.
3323 // b> the method belongs to the same context: there is no need to insert a
3324 // new entry.
3325 // If the method's declaration does not match the list, we insert it to the
3326 // end.
3327 if (!SameDeclaration ||
3328 !isMethodContextSameForKindofLookup(Method, List->getMethod())) {
3329 // Even if two method types do not match, we would like to say
3330 // there is more than one declaration so unavailability/deprecated
3331 // warning is not too noisy.
3332 if (!Method->isDefined())
3333 List->setHasMoreThanOneDecl(true);
3334
3335 // For methods with the same declaration, the one that is deprecated
3336 // should be put in the front for better diagnostics.
3337 if (Method->isDeprecated() && SameDeclaration &&
3338 !ListWithSameDeclaration && !List->getMethod()->isDeprecated())
3339 ListWithSameDeclaration = List;
3340
3341 if (Method->isUnavailable() && SameDeclaration &&
3342 !ListWithSameDeclaration &&
3343 List->getMethod()->getAvailability() < AR_Deprecated)
3344 ListWithSameDeclaration = List;
3345 continue;
3346 }
3347
3348 ObjCMethodDecl *PrevObjCMethod = List->getMethod();
3349
3350 // Propagate the 'defined' bit.
3351 if (Method->isDefined())
3352 PrevObjCMethod->setDefined(true);
3353 else {
3354 // Objective-C doesn't allow an @interface for a class after its
3355 // @implementation. So if Method is not defined and there already is
3356 // an entry for this type signature, Method has to be for a different
3357 // class than PrevObjCMethod.
3358 List->setHasMoreThanOneDecl(true);
3359 }
3360
3361 // If a method is deprecated, push it in the global pool.
3362 // This is used for better diagnostics.
3363 if (Method->isDeprecated()) {
3364 if (!PrevObjCMethod->isDeprecated())
3365 List->setMethod(Method);
3366 }
3367 // If the new method is unavailable, push it into global pool
3368 // unless previous one is deprecated.
3369 if (Method->isUnavailable()) {
3370 if (PrevObjCMethod->getAvailability() < AR_Deprecated)
3371 List->setMethod(Method);
3372 }
3373
3374 return;
3375 }
3376
3377 // We have a new signature for an existing method - add it.
3378 // This is extremely rare. Only 1% of Cocoa selectors are "overloaded".
3379 ObjCMethodList *Mem = BumpAlloc.Allocate<ObjCMethodList>();
3380
3381 // We insert it right before ListWithSameDeclaration.
3382 if (ListWithSameDeclaration) {
3383 auto *List = new (Mem) ObjCMethodList(*ListWithSameDeclaration);
3384 // FIXME: should we clear the other bits in ListWithSameDeclaration?
3385 ListWithSameDeclaration->setMethod(Method);
3386 ListWithSameDeclaration->setNext(List);
3387 return;
3388 }
3389
3390 Previous->setNext(new (Mem) ObjCMethodList(Method));
3391 }
3392
3393 /// Read the contents of the method pool for a given selector from
3394 /// external storage.
ReadMethodPool(Selector Sel)3395 void Sema::ReadMethodPool(Selector Sel) {
3396 assert(ExternalSource && "We need an external AST source");
3397 ExternalSource->ReadMethodPool(Sel);
3398 }
3399
updateOutOfDateSelector(Selector Sel)3400 void Sema::updateOutOfDateSelector(Selector Sel) {
3401 if (!ExternalSource)
3402 return;
3403 ExternalSource->updateOutOfDateSelector(Sel);
3404 }
3405
AddMethodToGlobalPool(ObjCMethodDecl * Method,bool impl,bool instance)3406 void Sema::AddMethodToGlobalPool(ObjCMethodDecl *Method, bool impl,
3407 bool instance) {
3408 // Ignore methods of invalid containers.
3409 if (cast<Decl>(Method->getDeclContext())->isInvalidDecl())
3410 return;
3411
3412 if (ExternalSource)
3413 ReadMethodPool(Method->getSelector());
3414
3415 GlobalMethodPool::iterator Pos = MethodPool.find(Method->getSelector());
3416 if (Pos == MethodPool.end())
3417 Pos = MethodPool.insert(std::make_pair(Method->getSelector(),
3418 GlobalMethods())).first;
3419
3420 Method->setDefined(impl);
3421
3422 ObjCMethodList &Entry = instance ? Pos->second.first : Pos->second.second;
3423 addMethodToGlobalList(&Entry, Method);
3424 }
3425
3426 /// Determines if this is an "acceptable" loose mismatch in the global
3427 /// method pool. This exists mostly as a hack to get around certain
3428 /// global mismatches which we can't afford to make warnings / errors.
3429 /// Really, what we want is a way to take a method out of the global
3430 /// method pool.
isAcceptableMethodMismatch(ObjCMethodDecl * chosen,ObjCMethodDecl * other)3431 static bool isAcceptableMethodMismatch(ObjCMethodDecl *chosen,
3432 ObjCMethodDecl *other) {
3433 if (!chosen->isInstanceMethod())
3434 return false;
3435
3436 if (chosen->isDirectMethod() != other->isDirectMethod())
3437 return false;
3438
3439 Selector sel = chosen->getSelector();
3440 if (!sel.isUnarySelector() || sel.getNameForSlot(0) != "length")
3441 return false;
3442
3443 // Don't complain about mismatches for -length if the method we
3444 // chose has an integral result type.
3445 return (chosen->getReturnType()->isIntegerType());
3446 }
3447
3448 /// Return true if the given method is wthin the type bound.
FilterMethodsByTypeBound(ObjCMethodDecl * Method,const ObjCObjectType * TypeBound)3449 static bool FilterMethodsByTypeBound(ObjCMethodDecl *Method,
3450 const ObjCObjectType *TypeBound) {
3451 if (!TypeBound)
3452 return true;
3453
3454 if (TypeBound->isObjCId())
3455 // FIXME: should we handle the case of bounding to id<A, B> differently?
3456 return true;
3457
3458 auto *BoundInterface = TypeBound->getInterface();
3459 assert(BoundInterface && "unexpected object type!");
3460
3461 // Check if the Method belongs to a protocol. We should allow any method
3462 // defined in any protocol, because any subclass could adopt the protocol.
3463 auto *MethodProtocol = dyn_cast<ObjCProtocolDecl>(Method->getDeclContext());
3464 if (MethodProtocol) {
3465 return true;
3466 }
3467
3468 // If the Method belongs to a class, check if it belongs to the class
3469 // hierarchy of the class bound.
3470 if (ObjCInterfaceDecl *MethodInterface = Method->getClassInterface()) {
3471 // We allow methods declared within classes that are part of the hierarchy
3472 // of the class bound (superclass of, subclass of, or the same as the class
3473 // bound).
3474 return MethodInterface == BoundInterface ||
3475 MethodInterface->isSuperClassOf(BoundInterface) ||
3476 BoundInterface->isSuperClassOf(MethodInterface);
3477 }
3478 llvm_unreachable("unknown method context");
3479 }
3480
3481 /// We first select the type of the method: Instance or Factory, then collect
3482 /// all methods with that type.
CollectMultipleMethodsInGlobalPool(Selector Sel,SmallVectorImpl<ObjCMethodDecl * > & Methods,bool InstanceFirst,bool CheckTheOther,const ObjCObjectType * TypeBound)3483 bool Sema::CollectMultipleMethodsInGlobalPool(
3484 Selector Sel, SmallVectorImpl<ObjCMethodDecl *> &Methods,
3485 bool InstanceFirst, bool CheckTheOther,
3486 const ObjCObjectType *TypeBound) {
3487 if (ExternalSource)
3488 ReadMethodPool(Sel);
3489
3490 GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3491 if (Pos == MethodPool.end())
3492 return false;
3493
3494 // Gather the non-hidden methods.
3495 ObjCMethodList &MethList = InstanceFirst ? Pos->second.first :
3496 Pos->second.second;
3497 for (ObjCMethodList *M = &MethList; M; M = M->getNext())
3498 if (M->getMethod() && M->getMethod()->isUnconditionallyVisible()) {
3499 if (FilterMethodsByTypeBound(M->getMethod(), TypeBound))
3500 Methods.push_back(M->getMethod());
3501 }
3502
3503 // Return if we find any method with the desired kind.
3504 if (!Methods.empty())
3505 return Methods.size() > 1;
3506
3507 if (!CheckTheOther)
3508 return false;
3509
3510 // Gather the other kind.
3511 ObjCMethodList &MethList2 = InstanceFirst ? Pos->second.second :
3512 Pos->second.first;
3513 for (ObjCMethodList *M = &MethList2; M; M = M->getNext())
3514 if (M->getMethod() && M->getMethod()->isUnconditionallyVisible()) {
3515 if (FilterMethodsByTypeBound(M->getMethod(), TypeBound))
3516 Methods.push_back(M->getMethod());
3517 }
3518
3519 return Methods.size() > 1;
3520 }
3521
AreMultipleMethodsInGlobalPool(Selector Sel,ObjCMethodDecl * BestMethod,SourceRange R,bool receiverIdOrClass,SmallVectorImpl<ObjCMethodDecl * > & Methods)3522 bool Sema::AreMultipleMethodsInGlobalPool(
3523 Selector Sel, ObjCMethodDecl *BestMethod, SourceRange R,
3524 bool receiverIdOrClass, SmallVectorImpl<ObjCMethodDecl *> &Methods) {
3525 // Diagnose finding more than one method in global pool.
3526 SmallVector<ObjCMethodDecl *, 4> FilteredMethods;
3527 FilteredMethods.push_back(BestMethod);
3528
3529 for (auto *M : Methods)
3530 if (M != BestMethod && !M->hasAttr<UnavailableAttr>())
3531 FilteredMethods.push_back(M);
3532
3533 if (FilteredMethods.size() > 1)
3534 DiagnoseMultipleMethodInGlobalPool(FilteredMethods, Sel, R,
3535 receiverIdOrClass);
3536
3537 GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3538 // Test for no method in the pool which should not trigger any warning by
3539 // caller.
3540 if (Pos == MethodPool.end())
3541 return true;
3542 ObjCMethodList &MethList =
3543 BestMethod->isInstanceMethod() ? Pos->second.first : Pos->second.second;
3544 return MethList.hasMoreThanOneDecl();
3545 }
3546
LookupMethodInGlobalPool(Selector Sel,SourceRange R,bool receiverIdOrClass,bool instance)3547 ObjCMethodDecl *Sema::LookupMethodInGlobalPool(Selector Sel, SourceRange R,
3548 bool receiverIdOrClass,
3549 bool instance) {
3550 if (ExternalSource)
3551 ReadMethodPool(Sel);
3552
3553 GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3554 if (Pos == MethodPool.end())
3555 return nullptr;
3556
3557 // Gather the non-hidden methods.
3558 ObjCMethodList &MethList = instance ? Pos->second.first : Pos->second.second;
3559 SmallVector<ObjCMethodDecl *, 4> Methods;
3560 for (ObjCMethodList *M = &MethList; M; M = M->getNext()) {
3561 if (M->getMethod() && M->getMethod()->isUnconditionallyVisible())
3562 return M->getMethod();
3563 }
3564 return nullptr;
3565 }
3566
DiagnoseMultipleMethodInGlobalPool(SmallVectorImpl<ObjCMethodDecl * > & Methods,Selector Sel,SourceRange R,bool receiverIdOrClass)3567 void Sema::DiagnoseMultipleMethodInGlobalPool(SmallVectorImpl<ObjCMethodDecl*> &Methods,
3568 Selector Sel, SourceRange R,
3569 bool receiverIdOrClass) {
3570 // We found multiple methods, so we may have to complain.
3571 bool issueDiagnostic = false, issueError = false;
3572
3573 // We support a warning which complains about *any* difference in
3574 // method signature.
3575 bool strictSelectorMatch =
3576 receiverIdOrClass &&
3577 !Diags.isIgnored(diag::warn_strict_multiple_method_decl, R.getBegin());
3578 if (strictSelectorMatch) {
3579 for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3580 if (!MatchTwoMethodDeclarations(Methods[0], Methods[I], MMS_strict)) {
3581 issueDiagnostic = true;
3582 break;
3583 }
3584 }
3585 }
3586
3587 // If we didn't see any strict differences, we won't see any loose
3588 // differences. In ARC, however, we also need to check for loose
3589 // mismatches, because most of them are errors.
3590 if (!strictSelectorMatch ||
3591 (issueDiagnostic && getLangOpts().ObjCAutoRefCount))
3592 for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3593 // This checks if the methods differ in type mismatch.
3594 if (!MatchTwoMethodDeclarations(Methods[0], Methods[I], MMS_loose) &&
3595 !isAcceptableMethodMismatch(Methods[0], Methods[I])) {
3596 issueDiagnostic = true;
3597 if (getLangOpts().ObjCAutoRefCount)
3598 issueError = true;
3599 break;
3600 }
3601 }
3602
3603 if (issueDiagnostic) {
3604 if (issueError)
3605 Diag(R.getBegin(), diag::err_arc_multiple_method_decl) << Sel << R;
3606 else if (strictSelectorMatch)
3607 Diag(R.getBegin(), diag::warn_strict_multiple_method_decl) << Sel << R;
3608 else
3609 Diag(R.getBegin(), diag::warn_multiple_method_decl) << Sel << R;
3610
3611 Diag(Methods[0]->getBeginLoc(),
3612 issueError ? diag::note_possibility : diag::note_using)
3613 << Methods[0]->getSourceRange();
3614 for (unsigned I = 1, N = Methods.size(); I != N; ++I) {
3615 Diag(Methods[I]->getBeginLoc(), diag::note_also_found)
3616 << Methods[I]->getSourceRange();
3617 }
3618 }
3619 }
3620
LookupImplementedMethodInGlobalPool(Selector Sel)3621 ObjCMethodDecl *Sema::LookupImplementedMethodInGlobalPool(Selector Sel) {
3622 GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
3623 if (Pos == MethodPool.end())
3624 return nullptr;
3625
3626 GlobalMethods &Methods = Pos->second;
3627 for (const ObjCMethodList *Method = &Methods.first; Method;
3628 Method = Method->getNext())
3629 if (Method->getMethod() &&
3630 (Method->getMethod()->isDefined() ||
3631 Method->getMethod()->isPropertyAccessor()))
3632 return Method->getMethod();
3633
3634 for (const ObjCMethodList *Method = &Methods.second; Method;
3635 Method = Method->getNext())
3636 if (Method->getMethod() &&
3637 (Method->getMethod()->isDefined() ||
3638 Method->getMethod()->isPropertyAccessor()))
3639 return Method->getMethod();
3640 return nullptr;
3641 }
3642
3643 static void
HelperSelectorsForTypoCorrection(SmallVectorImpl<const ObjCMethodDecl * > & BestMethod,StringRef Typo,const ObjCMethodDecl * Method)3644 HelperSelectorsForTypoCorrection(
3645 SmallVectorImpl<const ObjCMethodDecl *> &BestMethod,
3646 StringRef Typo, const ObjCMethodDecl * Method) {
3647 const unsigned MaxEditDistance = 1;
3648 unsigned BestEditDistance = MaxEditDistance + 1;
3649 std::string MethodName = Method->getSelector().getAsString();
3650
3651 unsigned MinPossibleEditDistance = abs((int)MethodName.size() - (int)Typo.size());
3652 if (MinPossibleEditDistance > 0 &&
3653 Typo.size() / MinPossibleEditDistance < 1)
3654 return;
3655 unsigned EditDistance = Typo.edit_distance(MethodName, true, MaxEditDistance);
3656 if (EditDistance > MaxEditDistance)
3657 return;
3658 if (EditDistance == BestEditDistance)
3659 BestMethod.push_back(Method);
3660 else if (EditDistance < BestEditDistance) {
3661 BestMethod.clear();
3662 BestMethod.push_back(Method);
3663 }
3664 }
3665
HelperIsMethodInObjCType(Sema & S,Selector Sel,QualType ObjectType)3666 static bool HelperIsMethodInObjCType(Sema &S, Selector Sel,
3667 QualType ObjectType) {
3668 if (ObjectType.isNull())
3669 return true;
3670 if (S.LookupMethodInObjectType(Sel, ObjectType, true/*Instance method*/))
3671 return true;
3672 return S.LookupMethodInObjectType(Sel, ObjectType, false/*Class method*/) !=
3673 nullptr;
3674 }
3675
3676 const ObjCMethodDecl *
SelectorsForTypoCorrection(Selector Sel,QualType ObjectType)3677 Sema::SelectorsForTypoCorrection(Selector Sel,
3678 QualType ObjectType) {
3679 unsigned NumArgs = Sel.getNumArgs();
3680 SmallVector<const ObjCMethodDecl *, 8> Methods;
3681 bool ObjectIsId = true, ObjectIsClass = true;
3682 if (ObjectType.isNull())
3683 ObjectIsId = ObjectIsClass = false;
3684 else if (!ObjectType->isObjCObjectPointerType())
3685 return nullptr;
3686 else if (const ObjCObjectPointerType *ObjCPtr =
3687 ObjectType->getAsObjCInterfacePointerType()) {
3688 ObjectType = QualType(ObjCPtr->getInterfaceType(), 0);
3689 ObjectIsId = ObjectIsClass = false;
3690 }
3691 else if (ObjectType->isObjCIdType() || ObjectType->isObjCQualifiedIdType())
3692 ObjectIsClass = false;
3693 else if (ObjectType->isObjCClassType() || ObjectType->isObjCQualifiedClassType())
3694 ObjectIsId = false;
3695 else
3696 return nullptr;
3697
3698 for (GlobalMethodPool::iterator b = MethodPool.begin(),
3699 e = MethodPool.end(); b != e; b++) {
3700 // instance methods
3701 for (ObjCMethodList *M = &b->second.first; M; M=M->getNext())
3702 if (M->getMethod() &&
3703 (M->getMethod()->getSelector().getNumArgs() == NumArgs) &&
3704 (M->getMethod()->getSelector() != Sel)) {
3705 if (ObjectIsId)
3706 Methods.push_back(M->getMethod());
3707 else if (!ObjectIsClass &&
3708 HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(),
3709 ObjectType))
3710 Methods.push_back(M->getMethod());
3711 }
3712 // class methods
3713 for (ObjCMethodList *M = &b->second.second; M; M=M->getNext())
3714 if (M->getMethod() &&
3715 (M->getMethod()->getSelector().getNumArgs() == NumArgs) &&
3716 (M->getMethod()->getSelector() != Sel)) {
3717 if (ObjectIsClass)
3718 Methods.push_back(M->getMethod());
3719 else if (!ObjectIsId &&
3720 HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(),
3721 ObjectType))
3722 Methods.push_back(M->getMethod());
3723 }
3724 }
3725
3726 SmallVector<const ObjCMethodDecl *, 8> SelectedMethods;
3727 for (unsigned i = 0, e = Methods.size(); i < e; i++) {
3728 HelperSelectorsForTypoCorrection(SelectedMethods,
3729 Sel.getAsString(), Methods[i]);
3730 }
3731 return (SelectedMethods.size() == 1) ? SelectedMethods[0] : nullptr;
3732 }
3733
3734 /// DiagnoseDuplicateIvars -
3735 /// Check for duplicate ivars in the entire class at the start of
3736 /// \@implementation. This becomes necesssary because class extension can
3737 /// add ivars to a class in random order which will not be known until
3738 /// class's \@implementation is seen.
DiagnoseDuplicateIvars(ObjCInterfaceDecl * ID,ObjCInterfaceDecl * SID)3739 void Sema::DiagnoseDuplicateIvars(ObjCInterfaceDecl *ID,
3740 ObjCInterfaceDecl *SID) {
3741 for (auto *Ivar : ID->ivars()) {
3742 if (Ivar->isInvalidDecl())
3743 continue;
3744 if (IdentifierInfo *II = Ivar->getIdentifier()) {
3745 ObjCIvarDecl* prevIvar = SID->lookupInstanceVariable(II);
3746 if (prevIvar) {
3747 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II;
3748 Diag(prevIvar->getLocation(), diag::note_previous_declaration);
3749 Ivar->setInvalidDecl();
3750 }
3751 }
3752 }
3753 }
3754
3755 /// Diagnose attempts to define ARC-__weak ivars when __weak is disabled.
DiagnoseWeakIvars(Sema & S,ObjCImplementationDecl * ID)3756 static void DiagnoseWeakIvars(Sema &S, ObjCImplementationDecl *ID) {
3757 if (S.getLangOpts().ObjCWeak) return;
3758
3759 for (auto ivar = ID->getClassInterface()->all_declared_ivar_begin();
3760 ivar; ivar = ivar->getNextIvar()) {
3761 if (ivar->isInvalidDecl()) continue;
3762 if (ivar->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
3763 if (S.getLangOpts().ObjCWeakRuntime) {
3764 S.Diag(ivar->getLocation(), diag::err_arc_weak_disabled);
3765 } else {
3766 S.Diag(ivar->getLocation(), diag::err_arc_weak_no_runtime);
3767 }
3768 }
3769 }
3770 }
3771
3772 /// Diagnose attempts to use flexible array member with retainable object type.
DiagnoseRetainableFlexibleArrayMember(Sema & S,ObjCInterfaceDecl * ID)3773 static void DiagnoseRetainableFlexibleArrayMember(Sema &S,
3774 ObjCInterfaceDecl *ID) {
3775 if (!S.getLangOpts().ObjCAutoRefCount)
3776 return;
3777
3778 for (auto ivar = ID->all_declared_ivar_begin(); ivar;
3779 ivar = ivar->getNextIvar()) {
3780 if (ivar->isInvalidDecl())
3781 continue;
3782 QualType IvarTy = ivar->getType();
3783 if (IvarTy->isIncompleteArrayType() &&
3784 (IvarTy.getObjCLifetime() != Qualifiers::OCL_ExplicitNone) &&
3785 IvarTy->isObjCLifetimeType()) {
3786 S.Diag(ivar->getLocation(), diag::err_flexible_array_arc_retainable);
3787 ivar->setInvalidDecl();
3788 }
3789 }
3790 }
3791
getObjCContainerKind() const3792 Sema::ObjCContainerKind Sema::getObjCContainerKind() const {
3793 switch (CurContext->getDeclKind()) {
3794 case Decl::ObjCInterface:
3795 return Sema::OCK_Interface;
3796 case Decl::ObjCProtocol:
3797 return Sema::OCK_Protocol;
3798 case Decl::ObjCCategory:
3799 if (cast<ObjCCategoryDecl>(CurContext)->IsClassExtension())
3800 return Sema::OCK_ClassExtension;
3801 return Sema::OCK_Category;
3802 case Decl::ObjCImplementation:
3803 return Sema::OCK_Implementation;
3804 case Decl::ObjCCategoryImpl:
3805 return Sema::OCK_CategoryImplementation;
3806
3807 default:
3808 return Sema::OCK_None;
3809 }
3810 }
3811
IsVariableSizedType(QualType T)3812 static bool IsVariableSizedType(QualType T) {
3813 if (T->isIncompleteArrayType())
3814 return true;
3815 const auto *RecordTy = T->getAs<RecordType>();
3816 return (RecordTy && RecordTy->getDecl()->hasFlexibleArrayMember());
3817 }
3818
DiagnoseVariableSizedIvars(Sema & S,ObjCContainerDecl * OCD)3819 static void DiagnoseVariableSizedIvars(Sema &S, ObjCContainerDecl *OCD) {
3820 ObjCInterfaceDecl *IntfDecl = nullptr;
3821 ObjCInterfaceDecl::ivar_range Ivars = llvm::make_range(
3822 ObjCInterfaceDecl::ivar_iterator(), ObjCInterfaceDecl::ivar_iterator());
3823 if ((IntfDecl = dyn_cast<ObjCInterfaceDecl>(OCD))) {
3824 Ivars = IntfDecl->ivars();
3825 } else if (auto *ImplDecl = dyn_cast<ObjCImplementationDecl>(OCD)) {
3826 IntfDecl = ImplDecl->getClassInterface();
3827 Ivars = ImplDecl->ivars();
3828 } else if (auto *CategoryDecl = dyn_cast<ObjCCategoryDecl>(OCD)) {
3829 if (CategoryDecl->IsClassExtension()) {
3830 IntfDecl = CategoryDecl->getClassInterface();
3831 Ivars = CategoryDecl->ivars();
3832 }
3833 }
3834
3835 // Check if variable sized ivar is in interface and visible to subclasses.
3836 if (!isa<ObjCInterfaceDecl>(OCD)) {
3837 for (auto ivar : Ivars) {
3838 if (!ivar->isInvalidDecl() && IsVariableSizedType(ivar->getType())) {
3839 S.Diag(ivar->getLocation(), diag::warn_variable_sized_ivar_visibility)
3840 << ivar->getDeclName() << ivar->getType();
3841 }
3842 }
3843 }
3844
3845 // Subsequent checks require interface decl.
3846 if (!IntfDecl)
3847 return;
3848
3849 // Check if variable sized ivar is followed by another ivar.
3850 for (ObjCIvarDecl *ivar = IntfDecl->all_declared_ivar_begin(); ivar;
3851 ivar = ivar->getNextIvar()) {
3852 if (ivar->isInvalidDecl() || !ivar->getNextIvar())
3853 continue;
3854 QualType IvarTy = ivar->getType();
3855 bool IsInvalidIvar = false;
3856 if (IvarTy->isIncompleteArrayType()) {
3857 S.Diag(ivar->getLocation(), diag::err_flexible_array_not_at_end)
3858 << ivar->getDeclName() << IvarTy
3859 << TTK_Class; // Use "class" for Obj-C.
3860 IsInvalidIvar = true;
3861 } else if (const RecordType *RecordTy = IvarTy->getAs<RecordType>()) {
3862 if (RecordTy->getDecl()->hasFlexibleArrayMember()) {
3863 S.Diag(ivar->getLocation(),
3864 diag::err_objc_variable_sized_type_not_at_end)
3865 << ivar->getDeclName() << IvarTy;
3866 IsInvalidIvar = true;
3867 }
3868 }
3869 if (IsInvalidIvar) {
3870 S.Diag(ivar->getNextIvar()->getLocation(),
3871 diag::note_next_ivar_declaration)
3872 << ivar->getNextIvar()->getSynthesize();
3873 ivar->setInvalidDecl();
3874 }
3875 }
3876
3877 // Check if ObjC container adds ivars after variable sized ivar in superclass.
3878 // Perform the check only if OCD is the first container to declare ivars to
3879 // avoid multiple warnings for the same ivar.
3880 ObjCIvarDecl *FirstIvar =
3881 (Ivars.begin() == Ivars.end()) ? nullptr : *Ivars.begin();
3882 if (FirstIvar && (FirstIvar == IntfDecl->all_declared_ivar_begin())) {
3883 const ObjCInterfaceDecl *SuperClass = IntfDecl->getSuperClass();
3884 while (SuperClass && SuperClass->ivar_empty())
3885 SuperClass = SuperClass->getSuperClass();
3886 if (SuperClass) {
3887 auto IvarIter = SuperClass->ivar_begin();
3888 std::advance(IvarIter, SuperClass->ivar_size() - 1);
3889 const ObjCIvarDecl *LastIvar = *IvarIter;
3890 if (IsVariableSizedType(LastIvar->getType())) {
3891 S.Diag(FirstIvar->getLocation(),
3892 diag::warn_superclass_variable_sized_type_not_at_end)
3893 << FirstIvar->getDeclName() << LastIvar->getDeclName()
3894 << LastIvar->getType() << SuperClass->getDeclName();
3895 S.Diag(LastIvar->getLocation(), diag::note_entity_declared_at)
3896 << LastIvar->getDeclName();
3897 }
3898 }
3899 }
3900 }
3901
3902 // Note: For class/category implementations, allMethods is always null.
ActOnAtEnd(Scope * S,SourceRange AtEnd,ArrayRef<Decl * > allMethods,ArrayRef<DeclGroupPtrTy> allTUVars)3903 Decl *Sema::ActOnAtEnd(Scope *S, SourceRange AtEnd, ArrayRef<Decl *> allMethods,
3904 ArrayRef<DeclGroupPtrTy> allTUVars) {
3905 if (getObjCContainerKind() == Sema::OCK_None)
3906 return nullptr;
3907
3908 assert(AtEnd.isValid() && "Invalid location for '@end'");
3909
3910 auto *OCD = cast<ObjCContainerDecl>(CurContext);
3911 Decl *ClassDecl = OCD;
3912
3913 bool isInterfaceDeclKind =
3914 isa<ObjCInterfaceDecl>(ClassDecl) || isa<ObjCCategoryDecl>(ClassDecl)
3915 || isa<ObjCProtocolDecl>(ClassDecl);
3916 bool checkIdenticalMethods = isa<ObjCImplementationDecl>(ClassDecl);
3917
3918 // Make synthesized accessor stub functions visible.
3919 // ActOnPropertyImplDecl() creates them as not visible in case
3920 // they are overridden by an explicit method that is encountered
3921 // later.
3922 if (auto *OID = dyn_cast<ObjCImplementationDecl>(CurContext)) {
3923 for (auto PropImpl : OID->property_impls()) {
3924 if (auto *Getter = PropImpl->getGetterMethodDecl())
3925 if (Getter->isSynthesizedAccessorStub()) {
3926 OID->makeDeclVisibleInContext(Getter);
3927 OID->addDecl(Getter);
3928 }
3929 if (auto *Setter = PropImpl->getSetterMethodDecl())
3930 if (Setter->isSynthesizedAccessorStub()) {
3931 OID->makeDeclVisibleInContext(Setter);
3932 OID->addDecl(Setter);
3933 }
3934 }
3935 }
3936
3937 // FIXME: Remove these and use the ObjCContainerDecl/DeclContext.
3938 llvm::DenseMap<Selector, const ObjCMethodDecl*> InsMap;
3939 llvm::DenseMap<Selector, const ObjCMethodDecl*> ClsMap;
3940
3941 for (unsigned i = 0, e = allMethods.size(); i != e; i++ ) {
3942 ObjCMethodDecl *Method =
3943 cast_or_null<ObjCMethodDecl>(allMethods[i]);
3944
3945 if (!Method) continue; // Already issued a diagnostic.
3946 if (Method->isInstanceMethod()) {
3947 /// Check for instance method of the same name with incompatible types
3948 const ObjCMethodDecl *&PrevMethod = InsMap[Method->getSelector()];
3949 bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod)
3950 : false;
3951 if ((isInterfaceDeclKind && PrevMethod && !match)
3952 || (checkIdenticalMethods && match)) {
3953 Diag(Method->getLocation(), diag::err_duplicate_method_decl)
3954 << Method->getDeclName();
3955 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
3956 Method->setInvalidDecl();
3957 } else {
3958 if (PrevMethod) {
3959 Method->setAsRedeclaration(PrevMethod);
3960 if (!Context.getSourceManager().isInSystemHeader(
3961 Method->getLocation()))
3962 Diag(Method->getLocation(), diag::warn_duplicate_method_decl)
3963 << Method->getDeclName();
3964 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
3965 }
3966 InsMap[Method->getSelector()] = Method;
3967 /// The following allows us to typecheck messages to "id".
3968 AddInstanceMethodToGlobalPool(Method);
3969 }
3970 } else {
3971 /// Check for class method of the same name with incompatible types
3972 const ObjCMethodDecl *&PrevMethod = ClsMap[Method->getSelector()];
3973 bool match = PrevMethod ? MatchTwoMethodDeclarations(Method, PrevMethod)
3974 : false;
3975 if ((isInterfaceDeclKind && PrevMethod && !match)
3976 || (checkIdenticalMethods && match)) {
3977 Diag(Method->getLocation(), diag::err_duplicate_method_decl)
3978 << Method->getDeclName();
3979 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
3980 Method->setInvalidDecl();
3981 } else {
3982 if (PrevMethod) {
3983 Method->setAsRedeclaration(PrevMethod);
3984 if (!Context.getSourceManager().isInSystemHeader(
3985 Method->getLocation()))
3986 Diag(Method->getLocation(), diag::warn_duplicate_method_decl)
3987 << Method->getDeclName();
3988 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
3989 }
3990 ClsMap[Method->getSelector()] = Method;
3991 AddFactoryMethodToGlobalPool(Method);
3992 }
3993 }
3994 }
3995 if (isa<ObjCInterfaceDecl>(ClassDecl)) {
3996 // Nothing to do here.
3997 } else if (ObjCCategoryDecl *C = dyn_cast<ObjCCategoryDecl>(ClassDecl)) {
3998 // Categories are used to extend the class by declaring new methods.
3999 // By the same token, they are also used to add new properties. No
4000 // need to compare the added property to those in the class.
4001
4002 if (C->IsClassExtension()) {
4003 ObjCInterfaceDecl *CCPrimary = C->getClassInterface();
4004 DiagnoseClassExtensionDupMethods(C, CCPrimary);
4005 }
4006 }
4007 if (ObjCContainerDecl *CDecl = dyn_cast<ObjCContainerDecl>(ClassDecl)) {
4008 if (CDecl->getIdentifier())
4009 // ProcessPropertyDecl is responsible for diagnosing conflicts with any
4010 // user-defined setter/getter. It also synthesizes setter/getter methods
4011 // and adds them to the DeclContext and global method pools.
4012 for (auto *I : CDecl->properties())
4013 ProcessPropertyDecl(I);
4014 CDecl->setAtEndRange(AtEnd);
4015 }
4016 if (ObjCImplementationDecl *IC=dyn_cast<ObjCImplementationDecl>(ClassDecl)) {
4017 IC->setAtEndRange(AtEnd);
4018 if (ObjCInterfaceDecl* IDecl = IC->getClassInterface()) {
4019 // Any property declared in a class extension might have user
4020 // declared setter or getter in current class extension or one
4021 // of the other class extensions. Mark them as synthesized as
4022 // property will be synthesized when property with same name is
4023 // seen in the @implementation.
4024 for (const auto *Ext : IDecl->visible_extensions()) {
4025 for (const auto *Property : Ext->instance_properties()) {
4026 // Skip over properties declared @dynamic
4027 if (const ObjCPropertyImplDecl *PIDecl
4028 = IC->FindPropertyImplDecl(Property->getIdentifier(),
4029 Property->getQueryKind()))
4030 if (PIDecl->getPropertyImplementation()
4031 == ObjCPropertyImplDecl::Dynamic)
4032 continue;
4033
4034 for (const auto *Ext : IDecl->visible_extensions()) {
4035 if (ObjCMethodDecl *GetterMethod =
4036 Ext->getInstanceMethod(Property->getGetterName()))
4037 GetterMethod->setPropertyAccessor(true);
4038 if (!Property->isReadOnly())
4039 if (ObjCMethodDecl *SetterMethod
4040 = Ext->getInstanceMethod(Property->getSetterName()))
4041 SetterMethod->setPropertyAccessor(true);
4042 }
4043 }
4044 }
4045 ImplMethodsVsClassMethods(S, IC, IDecl);
4046 AtomicPropertySetterGetterRules(IC, IDecl);
4047 DiagnoseOwningPropertyGetterSynthesis(IC);
4048 DiagnoseUnusedBackingIvarInAccessor(S, IC);
4049 if (IDecl->hasDesignatedInitializers())
4050 DiagnoseMissingDesignatedInitOverrides(IC, IDecl);
4051 DiagnoseWeakIvars(*this, IC);
4052 DiagnoseRetainableFlexibleArrayMember(*this, IDecl);
4053
4054 bool HasRootClassAttr = IDecl->hasAttr<ObjCRootClassAttr>();
4055 if (IDecl->getSuperClass() == nullptr) {
4056 // This class has no superclass, so check that it has been marked with
4057 // __attribute((objc_root_class)).
4058 if (!HasRootClassAttr) {
4059 SourceLocation DeclLoc(IDecl->getLocation());
4060 SourceLocation SuperClassLoc(getLocForEndOfToken(DeclLoc));
4061 Diag(DeclLoc, diag::warn_objc_root_class_missing)
4062 << IDecl->getIdentifier();
4063 // See if NSObject is in the current scope, and if it is, suggest
4064 // adding " : NSObject " to the class declaration.
4065 NamedDecl *IF = LookupSingleName(TUScope,
4066 NSAPIObj->getNSClassId(NSAPI::ClassId_NSObject),
4067 DeclLoc, LookupOrdinaryName);
4068 ObjCInterfaceDecl *NSObjectDecl = dyn_cast_or_null<ObjCInterfaceDecl>(IF);
4069 if (NSObjectDecl && NSObjectDecl->getDefinition()) {
4070 Diag(SuperClassLoc, diag::note_objc_needs_superclass)
4071 << FixItHint::CreateInsertion(SuperClassLoc, " : NSObject ");
4072 } else {
4073 Diag(SuperClassLoc, diag::note_objc_needs_superclass);
4074 }
4075 }
4076 } else if (HasRootClassAttr) {
4077 // Complain that only root classes may have this attribute.
4078 Diag(IDecl->getLocation(), diag::err_objc_root_class_subclass);
4079 }
4080
4081 if (const ObjCInterfaceDecl *Super = IDecl->getSuperClass()) {
4082 // An interface can subclass another interface with a
4083 // objc_subclassing_restricted attribute when it has that attribute as
4084 // well (because of interfaces imported from Swift). Therefore we have
4085 // to check if we can subclass in the implementation as well.
4086 if (IDecl->hasAttr<ObjCSubclassingRestrictedAttr>() &&
4087 Super->hasAttr<ObjCSubclassingRestrictedAttr>()) {
4088 Diag(IC->getLocation(), diag::err_restricted_superclass_mismatch);
4089 Diag(Super->getLocation(), diag::note_class_declared);
4090 }
4091 }
4092
4093 if (IDecl->hasAttr<ObjCClassStubAttr>())
4094 Diag(IC->getLocation(), diag::err_implementation_of_class_stub);
4095
4096 if (LangOpts.ObjCRuntime.isNonFragile()) {
4097 while (IDecl->getSuperClass()) {
4098 DiagnoseDuplicateIvars(IDecl, IDecl->getSuperClass());
4099 IDecl = IDecl->getSuperClass();
4100 }
4101 }
4102 }
4103 SetIvarInitializers(IC);
4104 } else if (ObjCCategoryImplDecl* CatImplClass =
4105 dyn_cast<ObjCCategoryImplDecl>(ClassDecl)) {
4106 CatImplClass->setAtEndRange(AtEnd);
4107
4108 // Find category interface decl and then check that all methods declared
4109 // in this interface are implemented in the category @implementation.
4110 if (ObjCInterfaceDecl* IDecl = CatImplClass->getClassInterface()) {
4111 if (ObjCCategoryDecl *Cat
4112 = IDecl->FindCategoryDeclaration(CatImplClass->getIdentifier())) {
4113 ImplMethodsVsClassMethods(S, CatImplClass, Cat);
4114 }
4115 }
4116 } else if (const auto *IntfDecl = dyn_cast<ObjCInterfaceDecl>(ClassDecl)) {
4117 if (const ObjCInterfaceDecl *Super = IntfDecl->getSuperClass()) {
4118 if (!IntfDecl->hasAttr<ObjCSubclassingRestrictedAttr>() &&
4119 Super->hasAttr<ObjCSubclassingRestrictedAttr>()) {
4120 Diag(IntfDecl->getLocation(), diag::err_restricted_superclass_mismatch);
4121 Diag(Super->getLocation(), diag::note_class_declared);
4122 }
4123 }
4124
4125 if (IntfDecl->hasAttr<ObjCClassStubAttr>() &&
4126 !IntfDecl->hasAttr<ObjCSubclassingRestrictedAttr>())
4127 Diag(IntfDecl->getLocation(), diag::err_class_stub_subclassing_mismatch);
4128 }
4129 DiagnoseVariableSizedIvars(*this, OCD);
4130 if (isInterfaceDeclKind) {
4131 // Reject invalid vardecls.
4132 for (unsigned i = 0, e = allTUVars.size(); i != e; i++) {
4133 DeclGroupRef DG = allTUVars[i].get();
4134 for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
4135 if (VarDecl *VDecl = dyn_cast<VarDecl>(*I)) {
4136 if (!VDecl->hasExternalStorage())
4137 Diag(VDecl->getLocation(), diag::err_objc_var_decl_inclass);
4138 }
4139 }
4140 }
4141 ActOnObjCContainerFinishDefinition();
4142
4143 for (unsigned i = 0, e = allTUVars.size(); i != e; i++) {
4144 DeclGroupRef DG = allTUVars[i].get();
4145 for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
4146 (*I)->setTopLevelDeclInObjCContainer();
4147 Consumer.HandleTopLevelDeclInObjCContainer(DG);
4148 }
4149
4150 ActOnDocumentableDecl(ClassDecl);
4151 return ClassDecl;
4152 }
4153
4154 /// CvtQTToAstBitMask - utility routine to produce an AST bitmask for
4155 /// objective-c's type qualifier from the parser version of the same info.
4156 static Decl::ObjCDeclQualifier
CvtQTToAstBitMask(ObjCDeclSpec::ObjCDeclQualifier PQTVal)4157 CvtQTToAstBitMask(ObjCDeclSpec::ObjCDeclQualifier PQTVal) {
4158 return (Decl::ObjCDeclQualifier) (unsigned) PQTVal;
4159 }
4160
4161 /// Check whether the declared result type of the given Objective-C
4162 /// method declaration is compatible with the method's class.
4163 ///
4164 static Sema::ResultTypeCompatibilityKind
CheckRelatedResultTypeCompatibility(Sema & S,ObjCMethodDecl * Method,ObjCInterfaceDecl * CurrentClass)4165 CheckRelatedResultTypeCompatibility(Sema &S, ObjCMethodDecl *Method,
4166 ObjCInterfaceDecl *CurrentClass) {
4167 QualType ResultType = Method->getReturnType();
4168
4169 // If an Objective-C method inherits its related result type, then its
4170 // declared result type must be compatible with its own class type. The
4171 // declared result type is compatible if:
4172 if (const ObjCObjectPointerType *ResultObjectType
4173 = ResultType->getAs<ObjCObjectPointerType>()) {
4174 // - it is id or qualified id, or
4175 if (ResultObjectType->isObjCIdType() ||
4176 ResultObjectType->isObjCQualifiedIdType())
4177 return Sema::RTC_Compatible;
4178
4179 if (CurrentClass) {
4180 if (ObjCInterfaceDecl *ResultClass
4181 = ResultObjectType->getInterfaceDecl()) {
4182 // - it is the same as the method's class type, or
4183 if (declaresSameEntity(CurrentClass, ResultClass))
4184 return Sema::RTC_Compatible;
4185
4186 // - it is a superclass of the method's class type
4187 if (ResultClass->isSuperClassOf(CurrentClass))
4188 return Sema::RTC_Compatible;
4189 }
4190 } else {
4191 // Any Objective-C pointer type might be acceptable for a protocol
4192 // method; we just don't know.
4193 return Sema::RTC_Unknown;
4194 }
4195 }
4196
4197 return Sema::RTC_Incompatible;
4198 }
4199
4200 namespace {
4201 /// A helper class for searching for methods which a particular method
4202 /// overrides.
4203 class OverrideSearch {
4204 public:
4205 const ObjCMethodDecl *Method;
4206 llvm::SmallSetVector<ObjCMethodDecl*, 4> Overridden;
4207 bool Recursive;
4208
4209 public:
OverrideSearch(Sema & S,const ObjCMethodDecl * method)4210 OverrideSearch(Sema &S, const ObjCMethodDecl *method) : Method(method) {
4211 Selector selector = method->getSelector();
4212
4213 // Bypass this search if we've never seen an instance/class method
4214 // with this selector before.
4215 Sema::GlobalMethodPool::iterator it = S.MethodPool.find(selector);
4216 if (it == S.MethodPool.end()) {
4217 if (!S.getExternalSource()) return;
4218 S.ReadMethodPool(selector);
4219
4220 it = S.MethodPool.find(selector);
4221 if (it == S.MethodPool.end())
4222 return;
4223 }
4224 const ObjCMethodList &list =
4225 method->isInstanceMethod() ? it->second.first : it->second.second;
4226 if (!list.getMethod()) return;
4227
4228 const ObjCContainerDecl *container
4229 = cast<ObjCContainerDecl>(method->getDeclContext());
4230
4231 // Prevent the search from reaching this container again. This is
4232 // important with categories, which override methods from the
4233 // interface and each other.
4234 if (const ObjCCategoryDecl *Category =
4235 dyn_cast<ObjCCategoryDecl>(container)) {
4236 searchFromContainer(container);
4237 if (const ObjCInterfaceDecl *Interface = Category->getClassInterface())
4238 searchFromContainer(Interface);
4239 } else {
4240 searchFromContainer(container);
4241 }
4242 }
4243
4244 typedef decltype(Overridden)::iterator iterator;
begin() const4245 iterator begin() const { return Overridden.begin(); }
end() const4246 iterator end() const { return Overridden.end(); }
4247
4248 private:
searchFromContainer(const ObjCContainerDecl * container)4249 void searchFromContainer(const ObjCContainerDecl *container) {
4250 if (container->isInvalidDecl()) return;
4251
4252 switch (container->getDeclKind()) {
4253 #define OBJCCONTAINER(type, base) \
4254 case Decl::type: \
4255 searchFrom(cast<type##Decl>(container)); \
4256 break;
4257 #define ABSTRACT_DECL(expansion)
4258 #define DECL(type, base) \
4259 case Decl::type:
4260 #include "clang/AST/DeclNodes.inc"
4261 llvm_unreachable("not an ObjC container!");
4262 }
4263 }
4264
searchFrom(const ObjCProtocolDecl * protocol)4265 void searchFrom(const ObjCProtocolDecl *protocol) {
4266 if (!protocol->hasDefinition())
4267 return;
4268
4269 // A method in a protocol declaration overrides declarations from
4270 // referenced ("parent") protocols.
4271 search(protocol->getReferencedProtocols());
4272 }
4273
searchFrom(const ObjCCategoryDecl * category)4274 void searchFrom(const ObjCCategoryDecl *category) {
4275 // A method in a category declaration overrides declarations from
4276 // the main class and from protocols the category references.
4277 // The main class is handled in the constructor.
4278 search(category->getReferencedProtocols());
4279 }
4280
searchFrom(const ObjCCategoryImplDecl * impl)4281 void searchFrom(const ObjCCategoryImplDecl *impl) {
4282 // A method in a category definition that has a category
4283 // declaration overrides declarations from the category
4284 // declaration.
4285 if (ObjCCategoryDecl *category = impl->getCategoryDecl()) {
4286 search(category);
4287 if (ObjCInterfaceDecl *Interface = category->getClassInterface())
4288 search(Interface);
4289
4290 // Otherwise it overrides declarations from the class.
4291 } else if (const auto *Interface = impl->getClassInterface()) {
4292 search(Interface);
4293 }
4294 }
4295
searchFrom(const ObjCInterfaceDecl * iface)4296 void searchFrom(const ObjCInterfaceDecl *iface) {
4297 // A method in a class declaration overrides declarations from
4298 if (!iface->hasDefinition())
4299 return;
4300
4301 // - categories,
4302 for (auto *Cat : iface->known_categories())
4303 search(Cat);
4304
4305 // - the super class, and
4306 if (ObjCInterfaceDecl *super = iface->getSuperClass())
4307 search(super);
4308
4309 // - any referenced protocols.
4310 search(iface->getReferencedProtocols());
4311 }
4312
searchFrom(const ObjCImplementationDecl * impl)4313 void searchFrom(const ObjCImplementationDecl *impl) {
4314 // A method in a class implementation overrides declarations from
4315 // the class interface.
4316 if (const auto *Interface = impl->getClassInterface())
4317 search(Interface);
4318 }
4319
search(const ObjCProtocolList & protocols)4320 void search(const ObjCProtocolList &protocols) {
4321 for (const auto *Proto : protocols)
4322 search(Proto);
4323 }
4324
search(const ObjCContainerDecl * container)4325 void search(const ObjCContainerDecl *container) {
4326 // Check for a method in this container which matches this selector.
4327 ObjCMethodDecl *meth = container->getMethod(Method->getSelector(),
4328 Method->isInstanceMethod(),
4329 /*AllowHidden=*/true);
4330
4331 // If we find one, record it and bail out.
4332 if (meth) {
4333 Overridden.insert(meth);
4334 return;
4335 }
4336
4337 // Otherwise, search for methods that a hypothetical method here
4338 // would have overridden.
4339
4340 // Note that we're now in a recursive case.
4341 Recursive = true;
4342
4343 searchFromContainer(container);
4344 }
4345 };
4346 } // end anonymous namespace
4347
CheckObjCMethodDirectOverrides(ObjCMethodDecl * method,ObjCMethodDecl * overridden)4348 void Sema::CheckObjCMethodDirectOverrides(ObjCMethodDecl *method,
4349 ObjCMethodDecl *overridden) {
4350 if (const auto *attr = overridden->getAttr<ObjCDirectAttr>()) {
4351 Diag(method->getLocation(), diag::err_objc_override_direct_method);
4352 Diag(attr->getLocation(), diag::note_previous_declaration);
4353 } else if (const auto *attr = method->getAttr<ObjCDirectAttr>()) {
4354 Diag(attr->getLocation(), diag::err_objc_direct_on_override)
4355 << isa<ObjCProtocolDecl>(overridden->getDeclContext());
4356 Diag(overridden->getLocation(), diag::note_previous_declaration);
4357 }
4358 }
4359
CheckObjCMethodOverrides(ObjCMethodDecl * ObjCMethod,ObjCInterfaceDecl * CurrentClass,ResultTypeCompatibilityKind RTC)4360 void Sema::CheckObjCMethodOverrides(ObjCMethodDecl *ObjCMethod,
4361 ObjCInterfaceDecl *CurrentClass,
4362 ResultTypeCompatibilityKind RTC) {
4363 if (!ObjCMethod)
4364 return;
4365 // Search for overridden methods and merge information down from them.
4366 OverrideSearch overrides(*this, ObjCMethod);
4367 // Keep track if the method overrides any method in the class's base classes,
4368 // its protocols, or its categories' protocols; we will keep that info
4369 // in the ObjCMethodDecl.
4370 // For this info, a method in an implementation is not considered as
4371 // overriding the same method in the interface or its categories.
4372 bool hasOverriddenMethodsInBaseOrProtocol = false;
4373 for (ObjCMethodDecl *overridden : overrides) {
4374 if (!hasOverriddenMethodsInBaseOrProtocol) {
4375 if (isa<ObjCProtocolDecl>(overridden->getDeclContext()) ||
4376 CurrentClass != overridden->getClassInterface() ||
4377 overridden->isOverriding()) {
4378 CheckObjCMethodDirectOverrides(ObjCMethod, overridden);
4379 hasOverriddenMethodsInBaseOrProtocol = true;
4380 } else if (isa<ObjCImplDecl>(ObjCMethod->getDeclContext())) {
4381 // OverrideSearch will return as "overridden" the same method in the
4382 // interface. For hasOverriddenMethodsInBaseOrProtocol, we need to
4383 // check whether a category of a base class introduced a method with the
4384 // same selector, after the interface method declaration.
4385 // To avoid unnecessary lookups in the majority of cases, we use the
4386 // extra info bits in GlobalMethodPool to check whether there were any
4387 // category methods with this selector.
4388 GlobalMethodPool::iterator It =
4389 MethodPool.find(ObjCMethod->getSelector());
4390 if (It != MethodPool.end()) {
4391 ObjCMethodList &List =
4392 ObjCMethod->isInstanceMethod()? It->second.first: It->second.second;
4393 unsigned CategCount = List.getBits();
4394 if (CategCount > 0) {
4395 // If the method is in a category we'll do lookup if there were at
4396 // least 2 category methods recorded, otherwise only one will do.
4397 if (CategCount > 1 ||
4398 !isa<ObjCCategoryImplDecl>(overridden->getDeclContext())) {
4399 OverrideSearch overrides(*this, overridden);
4400 for (ObjCMethodDecl *SuperOverridden : overrides) {
4401 if (isa<ObjCProtocolDecl>(SuperOverridden->getDeclContext()) ||
4402 CurrentClass != SuperOverridden->getClassInterface()) {
4403 CheckObjCMethodDirectOverrides(ObjCMethod, SuperOverridden);
4404 hasOverriddenMethodsInBaseOrProtocol = true;
4405 overridden->setOverriding(true);
4406 break;
4407 }
4408 }
4409 }
4410 }
4411 }
4412 }
4413 }
4414
4415 // Propagate down the 'related result type' bit from overridden methods.
4416 if (RTC != Sema::RTC_Incompatible && overridden->hasRelatedResultType())
4417 ObjCMethod->setRelatedResultType();
4418
4419 // Then merge the declarations.
4420 mergeObjCMethodDecls(ObjCMethod, overridden);
4421
4422 if (ObjCMethod->isImplicit() && overridden->isImplicit())
4423 continue; // Conflicting properties are detected elsewhere.
4424
4425 // Check for overriding methods
4426 if (isa<ObjCInterfaceDecl>(ObjCMethod->getDeclContext()) ||
4427 isa<ObjCImplementationDecl>(ObjCMethod->getDeclContext()))
4428 CheckConflictingOverridingMethod(ObjCMethod, overridden,
4429 isa<ObjCProtocolDecl>(overridden->getDeclContext()));
4430
4431 if (CurrentClass && overridden->getDeclContext() != CurrentClass &&
4432 isa<ObjCInterfaceDecl>(overridden->getDeclContext()) &&
4433 !overridden->isImplicit() /* not meant for properties */) {
4434 ObjCMethodDecl::param_iterator ParamI = ObjCMethod->param_begin(),
4435 E = ObjCMethod->param_end();
4436 ObjCMethodDecl::param_iterator PrevI = overridden->param_begin(),
4437 PrevE = overridden->param_end();
4438 for (; ParamI != E && PrevI != PrevE; ++ParamI, ++PrevI) {
4439 assert(PrevI != overridden->param_end() && "Param mismatch");
4440 QualType T1 = Context.getCanonicalType((*ParamI)->getType());
4441 QualType T2 = Context.getCanonicalType((*PrevI)->getType());
4442 // If type of argument of method in this class does not match its
4443 // respective argument type in the super class method, issue warning;
4444 if (!Context.typesAreCompatible(T1, T2)) {
4445 Diag((*ParamI)->getLocation(), diag::ext_typecheck_base_super)
4446 << T1 << T2;
4447 Diag(overridden->getLocation(), diag::note_previous_declaration);
4448 break;
4449 }
4450 }
4451 }
4452 }
4453
4454 ObjCMethod->setOverriding(hasOverriddenMethodsInBaseOrProtocol);
4455 }
4456
4457 /// Merge type nullability from for a redeclaration of the same entity,
4458 /// producing the updated type of the redeclared entity.
mergeTypeNullabilityForRedecl(Sema & S,SourceLocation loc,QualType type,bool usesCSKeyword,SourceLocation prevLoc,QualType prevType,bool prevUsesCSKeyword)4459 static QualType mergeTypeNullabilityForRedecl(Sema &S, SourceLocation loc,
4460 QualType type,
4461 bool usesCSKeyword,
4462 SourceLocation prevLoc,
4463 QualType prevType,
4464 bool prevUsesCSKeyword) {
4465 // Determine the nullability of both types.
4466 auto nullability = type->getNullability(S.Context);
4467 auto prevNullability = prevType->getNullability(S.Context);
4468
4469 // Easy case: both have nullability.
4470 if (nullability.hasValue() == prevNullability.hasValue()) {
4471 // Neither has nullability; continue.
4472 if (!nullability)
4473 return type;
4474
4475 // The nullabilities are equivalent; do nothing.
4476 if (*nullability == *prevNullability)
4477 return type;
4478
4479 // Complain about mismatched nullability.
4480 S.Diag(loc, diag::err_nullability_conflicting)
4481 << DiagNullabilityKind(*nullability, usesCSKeyword)
4482 << DiagNullabilityKind(*prevNullability, prevUsesCSKeyword);
4483 return type;
4484 }
4485
4486 // If it's the redeclaration that has nullability, don't change anything.
4487 if (nullability)
4488 return type;
4489
4490 // Otherwise, provide the result with the same nullability.
4491 return S.Context.getAttributedType(
4492 AttributedType::getNullabilityAttrKind(*prevNullability),
4493 type, type);
4494 }
4495
4496 /// Merge information from the declaration of a method in the \@interface
4497 /// (or a category/extension) into the corresponding method in the
4498 /// @implementation (for a class or category).
mergeInterfaceMethodToImpl(Sema & S,ObjCMethodDecl * method,ObjCMethodDecl * prevMethod)4499 static void mergeInterfaceMethodToImpl(Sema &S,
4500 ObjCMethodDecl *method,
4501 ObjCMethodDecl *prevMethod) {
4502 // Merge the objc_requires_super attribute.
4503 if (prevMethod->hasAttr<ObjCRequiresSuperAttr>() &&
4504 !method->hasAttr<ObjCRequiresSuperAttr>()) {
4505 // merge the attribute into implementation.
4506 method->addAttr(
4507 ObjCRequiresSuperAttr::CreateImplicit(S.Context,
4508 method->getLocation()));
4509 }
4510
4511 // Merge nullability of the result type.
4512 QualType newReturnType
4513 = mergeTypeNullabilityForRedecl(
4514 S, method->getReturnTypeSourceRange().getBegin(),
4515 method->getReturnType(),
4516 method->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability,
4517 prevMethod->getReturnTypeSourceRange().getBegin(),
4518 prevMethod->getReturnType(),
4519 prevMethod->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability);
4520 method->setReturnType(newReturnType);
4521
4522 // Handle each of the parameters.
4523 unsigned numParams = method->param_size();
4524 unsigned numPrevParams = prevMethod->param_size();
4525 for (unsigned i = 0, n = std::min(numParams, numPrevParams); i != n; ++i) {
4526 ParmVarDecl *param = method->param_begin()[i];
4527 ParmVarDecl *prevParam = prevMethod->param_begin()[i];
4528
4529 // Merge nullability.
4530 QualType newParamType
4531 = mergeTypeNullabilityForRedecl(
4532 S, param->getLocation(), param->getType(),
4533 param->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability,
4534 prevParam->getLocation(), prevParam->getType(),
4535 prevParam->getObjCDeclQualifier() & Decl::OBJC_TQ_CSNullability);
4536 param->setType(newParamType);
4537 }
4538 }
4539
4540 /// Verify that the method parameters/return value have types that are supported
4541 /// by the x86 target.
checkObjCMethodX86VectorTypes(Sema & SemaRef,const ObjCMethodDecl * Method)4542 static void checkObjCMethodX86VectorTypes(Sema &SemaRef,
4543 const ObjCMethodDecl *Method) {
4544 assert(SemaRef.getASTContext().getTargetInfo().getTriple().getArch() ==
4545 llvm::Triple::x86 &&
4546 "x86-specific check invoked for a different target");
4547 SourceLocation Loc;
4548 QualType T;
4549 for (const ParmVarDecl *P : Method->parameters()) {
4550 if (P->getType()->isVectorType()) {
4551 Loc = P->getBeginLoc();
4552 T = P->getType();
4553 break;
4554 }
4555 }
4556 if (Loc.isInvalid()) {
4557 if (Method->getReturnType()->isVectorType()) {
4558 Loc = Method->getReturnTypeSourceRange().getBegin();
4559 T = Method->getReturnType();
4560 } else
4561 return;
4562 }
4563
4564 // Vector parameters/return values are not supported by objc_msgSend on x86 in
4565 // iOS < 9 and macOS < 10.11.
4566 const auto &Triple = SemaRef.getASTContext().getTargetInfo().getTriple();
4567 VersionTuple AcceptedInVersion;
4568 if (Triple.getOS() == llvm::Triple::IOS)
4569 AcceptedInVersion = VersionTuple(/*Major=*/9);
4570 else if (Triple.isMacOSX())
4571 AcceptedInVersion = VersionTuple(/*Major=*/10, /*Minor=*/11);
4572 else
4573 return;
4574 if (SemaRef.getASTContext().getTargetInfo().getPlatformMinVersion() >=
4575 AcceptedInVersion)
4576 return;
4577 SemaRef.Diag(Loc, diag::err_objc_method_unsupported_param_ret_type)
4578 << T << (Method->getReturnType()->isVectorType() ? /*return value*/ 1
4579 : /*parameter*/ 0)
4580 << (Triple.isMacOSX() ? "macOS 10.11" : "iOS 9");
4581 }
4582
mergeObjCDirectMembers(Sema & S,Decl * CD,ObjCMethodDecl * Method)4583 static void mergeObjCDirectMembers(Sema &S, Decl *CD, ObjCMethodDecl *Method) {
4584 if (!Method->isDirectMethod() && !Method->hasAttr<UnavailableAttr>() &&
4585 CD->hasAttr<ObjCDirectMembersAttr>()) {
4586 Method->addAttr(
4587 ObjCDirectAttr::CreateImplicit(S.Context, Method->getLocation()));
4588 }
4589 }
4590
checkObjCDirectMethodClashes(Sema & S,ObjCInterfaceDecl * IDecl,ObjCMethodDecl * Method,ObjCImplDecl * ImpDecl=nullptr)4591 static void checkObjCDirectMethodClashes(Sema &S, ObjCInterfaceDecl *IDecl,
4592 ObjCMethodDecl *Method,
4593 ObjCImplDecl *ImpDecl = nullptr) {
4594 auto Sel = Method->getSelector();
4595 bool isInstance = Method->isInstanceMethod();
4596 bool diagnosed = false;
4597
4598 auto diagClash = [&](const ObjCMethodDecl *IMD) {
4599 if (diagnosed || IMD->isImplicit())
4600 return;
4601 if (Method->isDirectMethod() || IMD->isDirectMethod()) {
4602 S.Diag(Method->getLocation(), diag::err_objc_direct_duplicate_decl)
4603 << Method->isDirectMethod() << /* method */ 0 << IMD->isDirectMethod()
4604 << Method->getDeclName();
4605 S.Diag(IMD->getLocation(), diag::note_previous_declaration);
4606 diagnosed = true;
4607 }
4608 };
4609
4610 // Look for any other declaration of this method anywhere we can see in this
4611 // compilation unit.
4612 //
4613 // We do not use IDecl->lookupMethod() because we have specific needs:
4614 //
4615 // - we absolutely do not need to walk protocols, because
4616 // diag::err_objc_direct_on_protocol has already been emitted
4617 // during parsing if there's a conflict,
4618 //
4619 // - when we do not find a match in a given @interface container,
4620 // we need to attempt looking it up in the @implementation block if the
4621 // translation unit sees it to find more clashes.
4622
4623 if (auto *IMD = IDecl->getMethod(Sel, isInstance))
4624 diagClash(IMD);
4625 else if (auto *Impl = IDecl->getImplementation())
4626 if (Impl != ImpDecl)
4627 if (auto *IMD = IDecl->getImplementation()->getMethod(Sel, isInstance))
4628 diagClash(IMD);
4629
4630 for (const auto *Cat : IDecl->visible_categories())
4631 if (auto *IMD = Cat->getMethod(Sel, isInstance))
4632 diagClash(IMD);
4633 else if (auto CatImpl = Cat->getImplementation())
4634 if (CatImpl != ImpDecl)
4635 if (auto *IMD = Cat->getMethod(Sel, isInstance))
4636 diagClash(IMD);
4637 }
4638
ActOnMethodDeclaration(Scope * S,SourceLocation MethodLoc,SourceLocation EndLoc,tok::TokenKind MethodType,ObjCDeclSpec & ReturnQT,ParsedType ReturnType,ArrayRef<SourceLocation> SelectorLocs,Selector Sel,ObjCArgInfo * ArgInfo,DeclaratorChunk::ParamInfo * CParamInfo,unsigned CNumArgs,const ParsedAttributesView & AttrList,tok::ObjCKeywordKind MethodDeclKind,bool isVariadic,bool MethodDefinition)4639 Decl *Sema::ActOnMethodDeclaration(
4640 Scope *S, SourceLocation MethodLoc, SourceLocation EndLoc,
4641 tok::TokenKind MethodType, ObjCDeclSpec &ReturnQT, ParsedType ReturnType,
4642 ArrayRef<SourceLocation> SelectorLocs, Selector Sel,
4643 // optional arguments. The number of types/arguments is obtained
4644 // from the Sel.getNumArgs().
4645 ObjCArgInfo *ArgInfo, DeclaratorChunk::ParamInfo *CParamInfo,
4646 unsigned CNumArgs, // c-style args
4647 const ParsedAttributesView &AttrList, tok::ObjCKeywordKind MethodDeclKind,
4648 bool isVariadic, bool MethodDefinition) {
4649 // Make sure we can establish a context for the method.
4650 if (!CurContext->isObjCContainer()) {
4651 Diag(MethodLoc, diag::err_missing_method_context);
4652 return nullptr;
4653 }
4654
4655 Decl *ClassDecl = cast<ObjCContainerDecl>(CurContext);
4656 QualType resultDeclType;
4657
4658 bool HasRelatedResultType = false;
4659 TypeSourceInfo *ReturnTInfo = nullptr;
4660 if (ReturnType) {
4661 resultDeclType = GetTypeFromParser(ReturnType, &ReturnTInfo);
4662
4663 if (CheckFunctionReturnType(resultDeclType, MethodLoc))
4664 return nullptr;
4665
4666 QualType bareResultType = resultDeclType;
4667 (void)AttributedType::stripOuterNullability(bareResultType);
4668 HasRelatedResultType = (bareResultType == Context.getObjCInstanceType());
4669 } else { // get the type for "id".
4670 resultDeclType = Context.getObjCIdType();
4671 Diag(MethodLoc, diag::warn_missing_method_return_type)
4672 << FixItHint::CreateInsertion(SelectorLocs.front(), "(id)");
4673 }
4674
4675 ObjCMethodDecl *ObjCMethod = ObjCMethodDecl::Create(
4676 Context, MethodLoc, EndLoc, Sel, resultDeclType, ReturnTInfo, CurContext,
4677 MethodType == tok::minus, isVariadic,
4678 /*isPropertyAccessor=*/false, /*isSynthesizedAccessorStub=*/false,
4679 /*isImplicitlyDeclared=*/false, /*isDefined=*/false,
4680 MethodDeclKind == tok::objc_optional ? ObjCMethodDecl::Optional
4681 : ObjCMethodDecl::Required,
4682 HasRelatedResultType);
4683
4684 SmallVector<ParmVarDecl*, 16> Params;
4685
4686 for (unsigned i = 0, e = Sel.getNumArgs(); i != e; ++i) {
4687 QualType ArgType;
4688 TypeSourceInfo *DI;
4689
4690 if (!ArgInfo[i].Type) {
4691 ArgType = Context.getObjCIdType();
4692 DI = nullptr;
4693 } else {
4694 ArgType = GetTypeFromParser(ArgInfo[i].Type, &DI);
4695 }
4696
4697 LookupResult R(*this, ArgInfo[i].Name, ArgInfo[i].NameLoc,
4698 LookupOrdinaryName, forRedeclarationInCurContext());
4699 LookupName(R, S);
4700 if (R.isSingleResult()) {
4701 NamedDecl *PrevDecl = R.getFoundDecl();
4702 if (S->isDeclScope(PrevDecl)) {
4703 Diag(ArgInfo[i].NameLoc,
4704 (MethodDefinition ? diag::warn_method_param_redefinition
4705 : diag::warn_method_param_declaration))
4706 << ArgInfo[i].Name;
4707 Diag(PrevDecl->getLocation(),
4708 diag::note_previous_declaration);
4709 }
4710 }
4711
4712 SourceLocation StartLoc = DI
4713 ? DI->getTypeLoc().getBeginLoc()
4714 : ArgInfo[i].NameLoc;
4715
4716 ParmVarDecl* Param = CheckParameter(ObjCMethod, StartLoc,
4717 ArgInfo[i].NameLoc, ArgInfo[i].Name,
4718 ArgType, DI, SC_None);
4719
4720 Param->setObjCMethodScopeInfo(i);
4721
4722 Param->setObjCDeclQualifier(
4723 CvtQTToAstBitMask(ArgInfo[i].DeclSpec.getObjCDeclQualifier()));
4724
4725 // Apply the attributes to the parameter.
4726 ProcessDeclAttributeList(TUScope, Param, ArgInfo[i].ArgAttrs);
4727 AddPragmaAttributes(TUScope, Param);
4728
4729 if (Param->hasAttr<BlocksAttr>()) {
4730 Diag(Param->getLocation(), diag::err_block_on_nonlocal);
4731 Param->setInvalidDecl();
4732 }
4733 S->AddDecl(Param);
4734 IdResolver.AddDecl(Param);
4735
4736 Params.push_back(Param);
4737 }
4738
4739 for (unsigned i = 0, e = CNumArgs; i != e; ++i) {
4740 ParmVarDecl *Param = cast<ParmVarDecl>(CParamInfo[i].Param);
4741 QualType ArgType = Param->getType();
4742 if (ArgType.isNull())
4743 ArgType = Context.getObjCIdType();
4744 else
4745 // Perform the default array/function conversions (C99 6.7.5.3p[7,8]).
4746 ArgType = Context.getAdjustedParameterType(ArgType);
4747
4748 Param->setDeclContext(ObjCMethod);
4749 Params.push_back(Param);
4750 }
4751
4752 ObjCMethod->setMethodParams(Context, Params, SelectorLocs);
4753 ObjCMethod->setObjCDeclQualifier(
4754 CvtQTToAstBitMask(ReturnQT.getObjCDeclQualifier()));
4755
4756 ProcessDeclAttributeList(TUScope, ObjCMethod, AttrList);
4757 AddPragmaAttributes(TUScope, ObjCMethod);
4758
4759 // Add the method now.
4760 const ObjCMethodDecl *PrevMethod = nullptr;
4761 if (ObjCImplDecl *ImpDecl = dyn_cast<ObjCImplDecl>(ClassDecl)) {
4762 if (MethodType == tok::minus) {
4763 PrevMethod = ImpDecl->getInstanceMethod(Sel);
4764 ImpDecl->addInstanceMethod(ObjCMethod);
4765 } else {
4766 PrevMethod = ImpDecl->getClassMethod(Sel);
4767 ImpDecl->addClassMethod(ObjCMethod);
4768 }
4769
4770 // If this method overrides a previous @synthesize declaration,
4771 // register it with the property. Linear search through all
4772 // properties here, because the autosynthesized stub hasn't been
4773 // made visible yet, so it can be overriden by a later
4774 // user-specified implementation.
4775 for (ObjCPropertyImplDecl *PropertyImpl : ImpDecl->property_impls()) {
4776 if (auto *Setter = PropertyImpl->getSetterMethodDecl())
4777 if (Setter->getSelector() == Sel &&
4778 Setter->isInstanceMethod() == ObjCMethod->isInstanceMethod()) {
4779 assert(Setter->isSynthesizedAccessorStub() && "autosynth stub expected");
4780 PropertyImpl->setSetterMethodDecl(ObjCMethod);
4781 }
4782 if (auto *Getter = PropertyImpl->getGetterMethodDecl())
4783 if (Getter->getSelector() == Sel &&
4784 Getter->isInstanceMethod() == ObjCMethod->isInstanceMethod()) {
4785 assert(Getter->isSynthesizedAccessorStub() && "autosynth stub expected");
4786 PropertyImpl->setGetterMethodDecl(ObjCMethod);
4787 break;
4788 }
4789 }
4790
4791 // A method is either tagged direct explicitly, or inherits it from its
4792 // canonical declaration.
4793 //
4794 // We have to do the merge upfront and not in mergeInterfaceMethodToImpl()
4795 // because IDecl->lookupMethod() returns more possible matches than just
4796 // the canonical declaration.
4797 if (!ObjCMethod->isDirectMethod()) {
4798 const ObjCMethodDecl *CanonicalMD = ObjCMethod->getCanonicalDecl();
4799 if (const auto *attr = CanonicalMD->getAttr<ObjCDirectAttr>()) {
4800 ObjCMethod->addAttr(
4801 ObjCDirectAttr::CreateImplicit(Context, attr->getLocation()));
4802 }
4803 }
4804
4805 // Merge information from the @interface declaration into the
4806 // @implementation.
4807 if (ObjCInterfaceDecl *IDecl = ImpDecl->getClassInterface()) {
4808 if (auto *IMD = IDecl->lookupMethod(ObjCMethod->getSelector(),
4809 ObjCMethod->isInstanceMethod())) {
4810 mergeInterfaceMethodToImpl(*this, ObjCMethod, IMD);
4811
4812 // The Idecl->lookupMethod() above will find declarations for ObjCMethod
4813 // in one of these places:
4814 //
4815 // (1) the canonical declaration in an @interface container paired
4816 // with the ImplDecl,
4817 // (2) non canonical declarations in @interface not paired with the
4818 // ImplDecl for the same Class,
4819 // (3) any superclass container.
4820 //
4821 // Direct methods only allow for canonical declarations in the matching
4822 // container (case 1).
4823 //
4824 // Direct methods overriding a superclass declaration (case 3) is
4825 // handled during overrides checks in CheckObjCMethodOverrides().
4826 //
4827 // We deal with same-class container mismatches (Case 2) here.
4828 if (IDecl == IMD->getClassInterface()) {
4829 auto diagContainerMismatch = [&] {
4830 int decl = 0, impl = 0;
4831
4832 if (auto *Cat = dyn_cast<ObjCCategoryDecl>(IMD->getDeclContext()))
4833 decl = Cat->IsClassExtension() ? 1 : 2;
4834
4835 if (isa<ObjCCategoryImplDecl>(ImpDecl))
4836 impl = 1 + (decl != 0);
4837
4838 Diag(ObjCMethod->getLocation(),
4839 diag::err_objc_direct_impl_decl_mismatch)
4840 << decl << impl;
4841 Diag(IMD->getLocation(), diag::note_previous_declaration);
4842 };
4843
4844 if (const auto *attr = ObjCMethod->getAttr<ObjCDirectAttr>()) {
4845 if (ObjCMethod->getCanonicalDecl() != IMD) {
4846 diagContainerMismatch();
4847 } else if (!IMD->isDirectMethod()) {
4848 Diag(attr->getLocation(), diag::err_objc_direct_missing_on_decl);
4849 Diag(IMD->getLocation(), diag::note_previous_declaration);
4850 }
4851 } else if (const auto *attr = IMD->getAttr<ObjCDirectAttr>()) {
4852 if (ObjCMethod->getCanonicalDecl() != IMD) {
4853 diagContainerMismatch();
4854 } else {
4855 ObjCMethod->addAttr(
4856 ObjCDirectAttr::CreateImplicit(Context, attr->getLocation()));
4857 }
4858 }
4859 }
4860
4861 // Warn about defining -dealloc in a category.
4862 if (isa<ObjCCategoryImplDecl>(ImpDecl) && IMD->isOverriding() &&
4863 ObjCMethod->getSelector().getMethodFamily() == OMF_dealloc) {
4864 Diag(ObjCMethod->getLocation(), diag::warn_dealloc_in_category)
4865 << ObjCMethod->getDeclName();
4866 }
4867 } else {
4868 mergeObjCDirectMembers(*this, ClassDecl, ObjCMethod);
4869 checkObjCDirectMethodClashes(*this, IDecl, ObjCMethod, ImpDecl);
4870 }
4871
4872 // Warn if a method declared in a protocol to which a category or
4873 // extension conforms is non-escaping and the implementation's method is
4874 // escaping.
4875 for (auto *C : IDecl->visible_categories())
4876 for (auto &P : C->protocols())
4877 if (auto *IMD = P->lookupMethod(ObjCMethod->getSelector(),
4878 ObjCMethod->isInstanceMethod())) {
4879 assert(ObjCMethod->parameters().size() ==
4880 IMD->parameters().size() &&
4881 "Methods have different number of parameters");
4882 auto OI = IMD->param_begin(), OE = IMD->param_end();
4883 auto NI = ObjCMethod->param_begin();
4884 for (; OI != OE; ++OI, ++NI)
4885 diagnoseNoescape(*NI, *OI, C, P, *this);
4886 }
4887 }
4888 } else {
4889 if (!isa<ObjCProtocolDecl>(ClassDecl)) {
4890 mergeObjCDirectMembers(*this, ClassDecl, ObjCMethod);
4891
4892 ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(ClassDecl);
4893 if (!IDecl)
4894 IDecl = cast<ObjCCategoryDecl>(ClassDecl)->getClassInterface();
4895 // For valid code, we should always know the primary interface
4896 // declaration by now, however for invalid code we'll keep parsing
4897 // but we won't find the primary interface and IDecl will be nil.
4898 if (IDecl)
4899 checkObjCDirectMethodClashes(*this, IDecl, ObjCMethod);
4900 }
4901
4902 cast<DeclContext>(ClassDecl)->addDecl(ObjCMethod);
4903 }
4904
4905 if (PrevMethod) {
4906 // You can never have two method definitions with the same name.
4907 Diag(ObjCMethod->getLocation(), diag::err_duplicate_method_decl)
4908 << ObjCMethod->getDeclName();
4909 Diag(PrevMethod->getLocation(), diag::note_previous_declaration);
4910 ObjCMethod->setInvalidDecl();
4911 return ObjCMethod;
4912 }
4913
4914 // If this Objective-C method does not have a related result type, but we
4915 // are allowed to infer related result types, try to do so based on the
4916 // method family.
4917 ObjCInterfaceDecl *CurrentClass = dyn_cast<ObjCInterfaceDecl>(ClassDecl);
4918 if (!CurrentClass) {
4919 if (ObjCCategoryDecl *Cat = dyn_cast<ObjCCategoryDecl>(ClassDecl))
4920 CurrentClass = Cat->getClassInterface();
4921 else if (ObjCImplDecl *Impl = dyn_cast<ObjCImplDecl>(ClassDecl))
4922 CurrentClass = Impl->getClassInterface();
4923 else if (ObjCCategoryImplDecl *CatImpl
4924 = dyn_cast<ObjCCategoryImplDecl>(ClassDecl))
4925 CurrentClass = CatImpl->getClassInterface();
4926 }
4927
4928 ResultTypeCompatibilityKind RTC
4929 = CheckRelatedResultTypeCompatibility(*this, ObjCMethod, CurrentClass);
4930
4931 CheckObjCMethodOverrides(ObjCMethod, CurrentClass, RTC);
4932
4933 bool ARCError = false;
4934 if (getLangOpts().ObjCAutoRefCount)
4935 ARCError = CheckARCMethodDecl(ObjCMethod);
4936
4937 // Infer the related result type when possible.
4938 if (!ARCError && RTC == Sema::RTC_Compatible &&
4939 !ObjCMethod->hasRelatedResultType() &&
4940 LangOpts.ObjCInferRelatedResultType) {
4941 bool InferRelatedResultType = false;
4942 switch (ObjCMethod->getMethodFamily()) {
4943 case OMF_None:
4944 case OMF_copy:
4945 case OMF_dealloc:
4946 case OMF_finalize:
4947 case OMF_mutableCopy:
4948 case OMF_release:
4949 case OMF_retainCount:
4950 case OMF_initialize:
4951 case OMF_performSelector:
4952 break;
4953
4954 case OMF_alloc:
4955 case OMF_new:
4956 InferRelatedResultType = ObjCMethod->isClassMethod();
4957 break;
4958
4959 case OMF_init:
4960 case OMF_autorelease:
4961 case OMF_retain:
4962 case OMF_self:
4963 InferRelatedResultType = ObjCMethod->isInstanceMethod();
4964 break;
4965 }
4966
4967 if (InferRelatedResultType &&
4968 !ObjCMethod->getReturnType()->isObjCIndependentClassType())
4969 ObjCMethod->setRelatedResultType();
4970 }
4971
4972 if (MethodDefinition &&
4973 Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
4974 checkObjCMethodX86VectorTypes(*this, ObjCMethod);
4975
4976 // + load method cannot have availability attributes. It get called on
4977 // startup, so it has to have the availability of the deployment target.
4978 if (const auto *attr = ObjCMethod->getAttr<AvailabilityAttr>()) {
4979 if (ObjCMethod->isClassMethod() &&
4980 ObjCMethod->getSelector().getAsString() == "load") {
4981 Diag(attr->getLocation(), diag::warn_availability_on_static_initializer)
4982 << 0;
4983 ObjCMethod->dropAttr<AvailabilityAttr>();
4984 }
4985 }
4986
4987 // Insert the invisible arguments, self and _cmd!
4988 ObjCMethod->createImplicitParams(Context, ObjCMethod->getClassInterface());
4989
4990 ActOnDocumentableDecl(ObjCMethod);
4991
4992 return ObjCMethod;
4993 }
4994
CheckObjCDeclScope(Decl * D)4995 bool Sema::CheckObjCDeclScope(Decl *D) {
4996 // Following is also an error. But it is caused by a missing @end
4997 // and diagnostic is issued elsewhere.
4998 if (isa<ObjCContainerDecl>(CurContext->getRedeclContext()))
4999 return false;
5000
5001 // If we switched context to translation unit while we are still lexically in
5002 // an objc container, it means the parser missed emitting an error.
5003 if (isa<TranslationUnitDecl>(getCurLexicalContext()->getRedeclContext()))
5004 return false;
5005
5006 Diag(D->getLocation(), diag::err_objc_decls_may_only_appear_in_global_scope);
5007 D->setInvalidDecl();
5008
5009 return true;
5010 }
5011
5012 /// Called whenever \@defs(ClassName) is encountered in the source. Inserts the
5013 /// instance variables of ClassName into Decls.
ActOnDefs(Scope * S,Decl * TagD,SourceLocation DeclStart,IdentifierInfo * ClassName,SmallVectorImpl<Decl * > & Decls)5014 void Sema::ActOnDefs(Scope *S, Decl *TagD, SourceLocation DeclStart,
5015 IdentifierInfo *ClassName,
5016 SmallVectorImpl<Decl*> &Decls) {
5017 // Check that ClassName is a valid class
5018 ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName, DeclStart);
5019 if (!Class) {
5020 Diag(DeclStart, diag::err_undef_interface) << ClassName;
5021 return;
5022 }
5023 if (LangOpts.ObjCRuntime.isNonFragile()) {
5024 Diag(DeclStart, diag::err_atdef_nonfragile_interface);
5025 return;
5026 }
5027
5028 // Collect the instance variables
5029 SmallVector<const ObjCIvarDecl*, 32> Ivars;
5030 Context.DeepCollectObjCIvars(Class, true, Ivars);
5031 // For each ivar, create a fresh ObjCAtDefsFieldDecl.
5032 for (unsigned i = 0; i < Ivars.size(); i++) {
5033 const FieldDecl* ID = Ivars[i];
5034 RecordDecl *Record = dyn_cast<RecordDecl>(TagD);
5035 Decl *FD = ObjCAtDefsFieldDecl::Create(Context, Record,
5036 /*FIXME: StartL=*/ID->getLocation(),
5037 ID->getLocation(),
5038 ID->getIdentifier(), ID->getType(),
5039 ID->getBitWidth());
5040 Decls.push_back(FD);
5041 }
5042
5043 // Introduce all of these fields into the appropriate scope.
5044 for (SmallVectorImpl<Decl*>::iterator D = Decls.begin();
5045 D != Decls.end(); ++D) {
5046 FieldDecl *FD = cast<FieldDecl>(*D);
5047 if (getLangOpts().CPlusPlus)
5048 PushOnScopeChains(FD, S);
5049 else if (RecordDecl *Record = dyn_cast<RecordDecl>(TagD))
5050 Record->addDecl(FD);
5051 }
5052 }
5053
5054 /// Build a type-check a new Objective-C exception variable declaration.
BuildObjCExceptionDecl(TypeSourceInfo * TInfo,QualType T,SourceLocation StartLoc,SourceLocation IdLoc,IdentifierInfo * Id,bool Invalid)5055 VarDecl *Sema::BuildObjCExceptionDecl(TypeSourceInfo *TInfo, QualType T,
5056 SourceLocation StartLoc,
5057 SourceLocation IdLoc,
5058 IdentifierInfo *Id,
5059 bool Invalid) {
5060 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage
5061 // duration shall not be qualified by an address-space qualifier."
5062 // Since all parameters have automatic store duration, they can not have
5063 // an address space.
5064 if (T.getAddressSpace() != LangAS::Default) {
5065 Diag(IdLoc, diag::err_arg_with_address_space);
5066 Invalid = true;
5067 }
5068
5069 // An @catch parameter must be an unqualified object pointer type;
5070 // FIXME: Recover from "NSObject foo" by inserting the * in "NSObject *foo"?
5071 if (Invalid) {
5072 // Don't do any further checking.
5073 } else if (T->isDependentType()) {
5074 // Okay: we don't know what this type will instantiate to.
5075 } else if (T->isObjCQualifiedIdType()) {
5076 Invalid = true;
5077 Diag(IdLoc, diag::err_illegal_qualifiers_on_catch_parm);
5078 } else if (T->isObjCIdType()) {
5079 // Okay: we don't know what this type will instantiate to.
5080 } else if (!T->isObjCObjectPointerType()) {
5081 Invalid = true;
5082 Diag(IdLoc, diag::err_catch_param_not_objc_type);
5083 } else if (!T->castAs<ObjCObjectPointerType>()->getInterfaceType()) {
5084 Invalid = true;
5085 Diag(IdLoc, diag::err_catch_param_not_objc_type);
5086 }
5087
5088 VarDecl *New = VarDecl::Create(Context, CurContext, StartLoc, IdLoc, Id,
5089 T, TInfo, SC_None);
5090 New->setExceptionVariable(true);
5091
5092 // In ARC, infer 'retaining' for variables of retainable type.
5093 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(New))
5094 Invalid = true;
5095
5096 if (Invalid)
5097 New->setInvalidDecl();
5098 return New;
5099 }
5100
ActOnObjCExceptionDecl(Scope * S,Declarator & D)5101 Decl *Sema::ActOnObjCExceptionDecl(Scope *S, Declarator &D) {
5102 const DeclSpec &DS = D.getDeclSpec();
5103
5104 // We allow the "register" storage class on exception variables because
5105 // GCC did, but we drop it completely. Any other storage class is an error.
5106 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) {
5107 Diag(DS.getStorageClassSpecLoc(), diag::warn_register_objc_catch_parm)
5108 << FixItHint::CreateRemoval(SourceRange(DS.getStorageClassSpecLoc()));
5109 } else if (DeclSpec::SCS SCS = DS.getStorageClassSpec()) {
5110 Diag(DS.getStorageClassSpecLoc(), diag::err_storage_spec_on_catch_parm)
5111 << DeclSpec::getSpecifierName(SCS);
5112 }
5113 if (DS.isInlineSpecified())
5114 Diag(DS.getInlineSpecLoc(), diag::err_inline_non_function)
5115 << getLangOpts().CPlusPlus17;
5116 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
5117 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
5118 diag::err_invalid_thread)
5119 << DeclSpec::getSpecifierName(TSCS);
5120 D.getMutableDeclSpec().ClearStorageClassSpecs();
5121
5122 DiagnoseFunctionSpecifiers(D.getDeclSpec());
5123
5124 // Check that there are no default arguments inside the type of this
5125 // exception object (C++ only).
5126 if (getLangOpts().CPlusPlus)
5127 CheckExtraCXXDefaultArguments(D);
5128
5129 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
5130 QualType ExceptionType = TInfo->getType();
5131
5132 VarDecl *New = BuildObjCExceptionDecl(TInfo, ExceptionType,
5133 D.getSourceRange().getBegin(),
5134 D.getIdentifierLoc(),
5135 D.getIdentifier(),
5136 D.isInvalidType());
5137
5138 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1).
5139 if (D.getCXXScopeSpec().isSet()) {
5140 Diag(D.getIdentifierLoc(), diag::err_qualified_objc_catch_parm)
5141 << D.getCXXScopeSpec().getRange();
5142 New->setInvalidDecl();
5143 }
5144
5145 // Add the parameter declaration into this scope.
5146 S->AddDecl(New);
5147 if (D.getIdentifier())
5148 IdResolver.AddDecl(New);
5149
5150 ProcessDeclAttributes(S, New, D);
5151
5152 if (New->hasAttr<BlocksAttr>())
5153 Diag(New->getLocation(), diag::err_block_on_nonlocal);
5154 return New;
5155 }
5156
5157 /// CollectIvarsToConstructOrDestruct - Collect those ivars which require
5158 /// initialization.
CollectIvarsToConstructOrDestruct(ObjCInterfaceDecl * OI,SmallVectorImpl<ObjCIvarDecl * > & Ivars)5159 void Sema::CollectIvarsToConstructOrDestruct(ObjCInterfaceDecl *OI,
5160 SmallVectorImpl<ObjCIvarDecl*> &Ivars) {
5161 for (ObjCIvarDecl *Iv = OI->all_declared_ivar_begin(); Iv;
5162 Iv= Iv->getNextIvar()) {
5163 QualType QT = Context.getBaseElementType(Iv->getType());
5164 if (QT->isRecordType())
5165 Ivars.push_back(Iv);
5166 }
5167 }
5168
DiagnoseUseOfUnimplementedSelectors()5169 void Sema::DiagnoseUseOfUnimplementedSelectors() {
5170 // Load referenced selectors from the external source.
5171 if (ExternalSource) {
5172 SmallVector<std::pair<Selector, SourceLocation>, 4> Sels;
5173 ExternalSource->ReadReferencedSelectors(Sels);
5174 for (unsigned I = 0, N = Sels.size(); I != N; ++I)
5175 ReferencedSelectors[Sels[I].first] = Sels[I].second;
5176 }
5177
5178 // Warning will be issued only when selector table is
5179 // generated (which means there is at lease one implementation
5180 // in the TU). This is to match gcc's behavior.
5181 if (ReferencedSelectors.empty() ||
5182 !Context.AnyObjCImplementation())
5183 return;
5184 for (auto &SelectorAndLocation : ReferencedSelectors) {
5185 Selector Sel = SelectorAndLocation.first;
5186 SourceLocation Loc = SelectorAndLocation.second;
5187 if (!LookupImplementedMethodInGlobalPool(Sel))
5188 Diag(Loc, diag::warn_unimplemented_selector) << Sel;
5189 }
5190 }
5191
5192 ObjCIvarDecl *
GetIvarBackingPropertyAccessor(const ObjCMethodDecl * Method,const ObjCPropertyDecl * & PDecl) const5193 Sema::GetIvarBackingPropertyAccessor(const ObjCMethodDecl *Method,
5194 const ObjCPropertyDecl *&PDecl) const {
5195 if (Method->isClassMethod())
5196 return nullptr;
5197 const ObjCInterfaceDecl *IDecl = Method->getClassInterface();
5198 if (!IDecl)
5199 return nullptr;
5200 Method = IDecl->lookupMethod(Method->getSelector(), /*isInstance=*/true,
5201 /*shallowCategoryLookup=*/false,
5202 /*followSuper=*/false);
5203 if (!Method || !Method->isPropertyAccessor())
5204 return nullptr;
5205 if ((PDecl = Method->findPropertyDecl()))
5206 if (ObjCIvarDecl *IV = PDecl->getPropertyIvarDecl()) {
5207 // property backing ivar must belong to property's class
5208 // or be a private ivar in class's implementation.
5209 // FIXME. fix the const-ness issue.
5210 IV = const_cast<ObjCInterfaceDecl *>(IDecl)->lookupInstanceVariable(
5211 IV->getIdentifier());
5212 return IV;
5213 }
5214 return nullptr;
5215 }
5216
5217 namespace {
5218 /// Used by Sema::DiagnoseUnusedBackingIvarInAccessor to check if a property
5219 /// accessor references the backing ivar.
5220 class UnusedBackingIvarChecker :
5221 public RecursiveASTVisitor<UnusedBackingIvarChecker> {
5222 public:
5223 Sema &S;
5224 const ObjCMethodDecl *Method;
5225 const ObjCIvarDecl *IvarD;
5226 bool AccessedIvar;
5227 bool InvokedSelfMethod;
5228
UnusedBackingIvarChecker(Sema & S,const ObjCMethodDecl * Method,const ObjCIvarDecl * IvarD)5229 UnusedBackingIvarChecker(Sema &S, const ObjCMethodDecl *Method,
5230 const ObjCIvarDecl *IvarD)
5231 : S(S), Method(Method), IvarD(IvarD),
5232 AccessedIvar(false), InvokedSelfMethod(false) {
5233 assert(IvarD);
5234 }
5235
VisitObjCIvarRefExpr(ObjCIvarRefExpr * E)5236 bool VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
5237 if (E->getDecl() == IvarD) {
5238 AccessedIvar = true;
5239 return false;
5240 }
5241 return true;
5242 }
5243
VisitObjCMessageExpr(ObjCMessageExpr * E)5244 bool VisitObjCMessageExpr(ObjCMessageExpr *E) {
5245 if (E->getReceiverKind() == ObjCMessageExpr::Instance &&
5246 S.isSelfExpr(E->getInstanceReceiver(), Method)) {
5247 InvokedSelfMethod = true;
5248 }
5249 return true;
5250 }
5251 };
5252 } // end anonymous namespace
5253
DiagnoseUnusedBackingIvarInAccessor(Scope * S,const ObjCImplementationDecl * ImplD)5254 void Sema::DiagnoseUnusedBackingIvarInAccessor(Scope *S,
5255 const ObjCImplementationDecl *ImplD) {
5256 if (S->hasUnrecoverableErrorOccurred())
5257 return;
5258
5259 for (const auto *CurMethod : ImplD->instance_methods()) {
5260 unsigned DIAG = diag::warn_unused_property_backing_ivar;
5261 SourceLocation Loc = CurMethod->getLocation();
5262 if (Diags.isIgnored(DIAG, Loc))
5263 continue;
5264
5265 const ObjCPropertyDecl *PDecl;
5266 const ObjCIvarDecl *IV = GetIvarBackingPropertyAccessor(CurMethod, PDecl);
5267 if (!IV)
5268 continue;
5269
5270 if (CurMethod->isSynthesizedAccessorStub())
5271 continue;
5272
5273 UnusedBackingIvarChecker Checker(*this, CurMethod, IV);
5274 Checker.TraverseStmt(CurMethod->getBody());
5275 if (Checker.AccessedIvar)
5276 continue;
5277
5278 // Do not issue this warning if backing ivar is used somewhere and accessor
5279 // implementation makes a self call. This is to prevent false positive in
5280 // cases where the ivar is accessed by another method that the accessor
5281 // delegates to.
5282 if (!IV->isReferenced() || !Checker.InvokedSelfMethod) {
5283 Diag(Loc, DIAG) << IV;
5284 Diag(PDecl->getLocation(), diag::note_property_declare);
5285 }
5286 }
5287 }
5288