Objective-C. Warn if protocol used in an @protocol

expression is a forward declaration as this results
in undefined behavior. rdar://17768630

llvm-svn: 213968

2 files changed, 18 insertions, 3 deletions

diff --git a/clang/test/SemaObjC/protocol-expr-1.m b/clang/test/SemaObjC/protocol-expr-1.m
index 94a0d9e3e8b..5ff3db474c7 100644
--- a/clang/test/SemaObjC/protocol-expr-1.m
+++ b/clang/test/SemaObjC/protocol-expr-1.m
@@ -1,7 +1,7 @@
 // RUN: %clang_cc1 -fsyntax-only -verify %s
 // expected-no-diagnostics
 
-@protocol fproto;
+@protocol fproto @end
 
 @protocol p1 
 @end
diff --git a/clang/test/SemaObjC/protocol-expr-neg-1.m b/clang/test/SemaObjC/protocol-expr-neg-1.m
index 58ac8c0ca32..aed56c016b0 100644
--- a/clang/test/SemaObjC/protocol-expr-neg-1.m
+++ b/clang/test/SemaObjC/protocol-expr-neg-1.m
@@ -2,7 +2,7 @@
 
 @class Protocol;
 
-@protocol fproto;
+@protocol fproto; // expected-note {{'fproto' declared here}}
 
 @protocol p1 
 @end
@@ -12,8 +12,23 @@
 int main()
 {
 	Protocol *proto = @protocol(p1);
-        Protocol *fproto = @protocol(fproto);
+        Protocol *fproto = @protocol(fproto); // expected-warning {{@protocol is using a forward protocol declaration of fproto}}
 	Protocol *pp = @protocol(i); // expected-error {{cannot find protocol declaration for 'i'}}
 	Protocol *p1p = @protocol(cl); // expected-error {{cannot find protocol declaration for 'cl'}}
 }
 
+// rdar://17768630
+@protocol SuperProtocol; // expected-note {{'SuperProtocol' declared here}}
+@protocol TestProtocol; // expected-note {{'TestProtocol' declared here}}
+
+@interface I
+- (int) conformsToProtocol : (Protocol *)protocl;
+@end
+
+int doesConform(id foo) {
+  return [foo conformsToProtocol:@protocol(TestProtocol)]; // expected-warning {{@protocol is using a forward protocol declaration of TestProtocol}}
+}
+
+int doesConformSuper(id foo) {
+  return [foo conformsToProtocol:@protocol(SuperProtocol)]; // expected-warning {{@protocol is using a forward protocol declaration of SuperProtocol}}
+}