Merging r351459:

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r351459 | arphaman | 2019-01-17 19:12:45 +0100 (Thu, 17 Jan 2019) | 13 lines

[ObjC] Follow-up r350768 and allow the use of unavailable methods that are
declared in a parent class from within the @implementation context

This commit extends r350768 and allows the use of methods marked as unavailable
that are declared in a parent class/category from within the @implementation of
the class where the method is marked as unavailable.
This allows users to call init that's marked as unavailable even if they don't
define it.

rdar://47134898

Differential Revision: https://reviews.llvm.org/D56816

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llvm-svn: 351535

clang/lib/Sema/SemaDeclAttr.cpp

@@ -7365,13 +7365,11 @@ ShouldDiagnoseAvailabilityInContext(Sema &S, AvailabilityResult K,
         return true;
     } else if (K == AR_Unavailable) {
       // It is perfectly fine to refer to an 'unavailable' Objective-C method
-      // when it's actually defined and is referenced from within the
-      // @implementation itself. In this context, we interpret unavailable as a
-      // form of access control.
+      // when it is referenced from within the @implementation itself. In this
+      // context, we interpret unavailable as a form of access control.
       if (const auto *MD = dyn_cast<ObjCMethodDecl>(OffendingDecl)) {
         if (const auto *Impl = dyn_cast<ObjCImplDecl>(C)) {
-          if (MD->getClassInterface() == Impl->getClassInterface() &&
-              MD->isDefined())
+          if (MD->getClassInterface() == Impl->getClassInterface())
             return true;
         }
       }

clang/test/SemaObjC/call-unavailable-init-in-self.m

@@ -5,13 +5,24 @@ @interface NSObject
 + (instancetype)new;
 + (instancetype)alloc;
 
+- (void)declaredInSuper;
+
+@end
+
+@interface NSObject (Category)
+
+- (void)declaredInSuperCategory;
+
 @end
 
 @interface Sub: NSObject
 
 - (instancetype)init __attribute__((unavailable)); // expected-note 4 {{'init' has been explicitly marked unavailable here}}
 
-- (void)notImplemented __attribute__((unavailable)); // expected-note {{'notImplemented' has been explicitly marked unavailable here}}
+- (void)notImplemented __attribute__((unavailable));
+
+- (void)declaredInSuper __attribute__((unavailable));
+- (void)declaredInSuperCategory __attribute__((unavailable));
 
 @end
 
@@ -34,7 +45,14 @@ - (instancetype) init {
 }
 
 - (void)reportUseOfUnimplemented {
-  [self notImplemented]; // expected-error {{'notImplemented' is unavailable}}
+  [self notImplemented];
+}
+
+- (void)allowSuperCallUsingSelf {
+  [self declaredInSuper];
+  [[Sub alloc] declaredInSuper];
+  [self declaredInSuperCategory];
+  [[Sub alloc] declaredInSuperCategory];
 }
 
 @end

clang/test/SemaObjC/infer-availability-from-init.m

@@ -47,12 +47,12 @@ void usenotmyobject() {
 }
 
 @interface FromSelf : NSObject
--(instancetype)init __attribute__((unavailable)); // expected-note {{'init' has been explicitly marked unavailable here}}
+-(instancetype)init __attribute__((unavailable));
 +(FromSelf*)another_one;
 @end
 
 @implementation FromSelf
 +(FromSelf*)another_one {
-  [self new]; // expected-error{{'new' is unavailable}}
+  [self new];
 }
 @end