Objective-C [Sema]. Fixes a bug in comparing qualified

Objective-C pointer types. In this case, checker incorrectly
claims incompatible pointer types if redundant protocol conformance 
is specified. rdar://18491222

llvm-svn: 219630

2 files changed, 40 insertions, 5 deletions

diff --git a/clang/test/SemaObjC/compare-qualified-class.m b/clang/test/SemaObjC/compare-qualified-class.m
index 60ef851e1f3..a5256152144 100644
--- a/clang/test/SemaObjC/compare-qualified-class.m
+++ b/clang/test/SemaObjC/compare-qualified-class.m
@@ -28,3 +28,38 @@ int main () {
            classA == classD; // expected-warning {{comparison of distinct pointer types ('Class<SomeProtocol>' and 'Class<SomeProtocol1>')}}
 }
 
+// rdar://18491222
+@protocol NSObject @end
+
+@interface NSObject @end
+@protocol ProtocolX <NSObject>
+@end
+
+@protocol ProtocolY <NSObject>
+@end
+
+@interface ClassA : NSObject
+@end
+
+@interface ClassB : ClassA <ProtocolY, ProtocolX>
+@end
+
+@interface OtherClass : NSObject
+@property (nonatomic, copy) ClassB<ProtocolX> *aProperty;
+- (ClassA<ProtocolY> *)aMethod;
+- (ClassA<ProtocolY> *)anotherMethod;
+@end
+
+@implementation OtherClass
+- (ClassA<ProtocolY> *)aMethod {
+    // This does not work, even though ClassB subclasses from A and conforms to Y
+    // because the property type explicity adds ProtocolX conformance
+    // even though ClassB already conforms to ProtocolX
+    return self.aProperty;
+}
+- (ClassA<ProtocolY> *)anotherMethod {
+    // This works, even though all it is doing is removing an explicit
+    // protocol conformance that ClassB already conforms to
+    return (ClassB *)self.aProperty;
+}
+@end
diff --git a/clang/test/SemaObjC/conditional-expr.m b/clang/test/SemaObjC/conditional-expr.m
index d8862c584a0..71e108cce67 100644
--- a/clang/test/SemaObjC/conditional-expr.m
+++ b/clang/test/SemaObjC/conditional-expr.m
@@ -101,10 +101,10 @@ int f8(int a, A<P0> *x, A *y) {
 }
 
 void f9(int a, A<P0> *x, A<P1> *y) {
-  id l0 = (a ? x : y ); // expected-warning {{incompatible operand types ('A<P0> *' and 'A<P1> *')}}
-  A<P0> *l1 = (a ? x : y ); // expected-warning {{incompatible operand types ('A<P0> *' and 'A<P1> *')}}
-  A<P1> *l2 = (a ? x : y ); // expected-warning {{incompatible operand types ('A<P0> *' and 'A<P1> *')}}
-  [ (a ? x : y ) intProp ]; // expected-warning {{incompatible operand types ('A<P0> *' and 'A<P1> *')}}
+  id l0 = (a ? x : y );     // Ok. y is of A<P1> object type and A is qualified by P0.
+  A<P0> *l1 = (a ? x : y ); // Ok. y is of A<P1> object type and A is qualified by P0.
+  A<P1> *l2 = (a ? x : y ); // expected-warning {{incompatible pointer types initializing 'A<P1> *' with an expression of type 'A<P0> *'}}
+  (void)[ (a ? x : y ) intProp ]; // Ok. Common type is A<P0> * and P0's property intProp is accessed.
 }
 
 void f10(int a, id<P0> x, id y) {
@@ -116,5 +116,5 @@ void f11(int a, id<P0> x, id<P1> y) {
 }
 
 void f12(int a, A<P0> *x, A<P1> *y) {
-  A<P1>* l0 = (a ? x : y ); // expected-warning {{incompatible operand types ('A<P0> *' and 'A<P1> *')}}
+  A<P1>* l0 = (a ? x : y ); // expected-warning {{incompatible pointer types initializing 'A<P1> *' with an expression of type 'A<P0> *'}}
 }