performSelectorの警告を消す
#define SuppressPerformSelectorLeakWarning(Stuff) \
do { \
_Pragma("clang diagnostic push") \
_Pragma("clang diagnostic ignored \"-Warc-performSelector-leaks\"") \
Stuff; \
_Pragma("clang diagnostic pop") \
} while (0)

if (_delegate && _selector && [_delegate respondsToSelector:_selector]) {
    SuppressPerformSelectorLeakWarning([_delegate performSelector:_selector withObject:[NSNumber numberWithBool:success]]);
}