typedef _Atomic(int)&atomic_int_ref;
typedef _Atomic int &atomic_int_ref;
-typedef _Atomic atomic_int_ref atomic_int_ref; // ok, qualifiers on references ignored in this case.
+typedef _Atomic atomic_int_ref atomic_int_ref; // expected-warning {{'_Atomic' qualifier on reference type 'atomic_int_ref' (aka '_Atomic(int) &') has no effect}}
typedef int &_Atomic atomic_reference_to_int; // expected-error {{'_Atomic' qualifier may not be applied to a reference}}
typedef _Atomic(int &) atomic_reference_to_int; // expected-error {{_Atomic cannot be applied to reference type 'int &'}}