|  | // RUN: %clang_cc1 -fobjc-arc -fobjc-runtime-has-weak -Wnonnull %s -verify | 
|  |  | 
|  | @interface NSObject @end | 
|  |  | 
|  | @interface Base : NSObject | 
|  | - (nonnull id)bad:(nullable id)obj; // expected-note 2 {{previous declaration is here}} | 
|  | - (nullable id)notAsBad:(nonnull id)obj; | 
|  | @end | 
|  |  | 
|  | @interface Sub : Base | 
|  | - (nullable id)bad:(nonnull id)obj; // expected-warning {{conflicting nullability specifier on return types, 'nullable' conflicts with existing specifier 'nonnull'}} \ | 
|  | // expected-warning {{conflicting nullability specifier on parameter types, 'nonnull' conflicts with existing specifier 'nullable'}} | 
|  | - (nonnull id)notAsBad:(nullable id)obj; | 
|  | @end |