Add test case for -Wdeprecated-objc-pointer-introspection, and
tweak warning to suggest that it is just a bad thing to do.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180175 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/SemaObjC/deprecated-objc-introspection.m b/test/SemaObjC/deprecated-objc-introspection.m
index 6d67641..faaef25 100644
--- a/test/SemaObjC/deprecated-objc-introspection.m
+++ b/test/SemaObjC/deprecated-objc-introspection.m
@@ -87,3 +87,11 @@
 }
 @end
 
+// Test for introspection of Objective-C pointers via bitmasking.
+
+void testBitmasking(NSObject *p) {
+  (void) (((NSUInteger) p) & 0x1); // expected-warning {{bitmasking for introspection of Objective-C object pointers is strongly discouraged}}
+  (void) (0x1 & ((NSUInteger) p)); // expected-warning {{bitmasking for introspection of Objective-C object pointers is strongly discouraged}}
+  (void) (((NSUInteger) p) ^ 0x1); // no-warning
+  (void) (0x1 ^ ((NSUInteger) p)); // no-warning
+}
\ No newline at end of file