__attribute(NSObject)__ test

AttributeTest.m

#import <Foundation/Foundation.h>

@interface TestClass : NSObject
@property (nonatomic, strong) __attribute__((NSObject)) CFStringRef str;
@end

@implementation TestClass
@end

int main(int argc, char* argv[]) {
	@autoreleasepool {
		CFStringRef str = CFStringCreateWithFormat(NULL, NULL, CFSTR("%f"), 2.5);
		TestClass *obj = [[TestClass alloc] init];
		obj.str = str;
		CFRelease(str), str = NULL;
		NSLog(@"obj.str %@", obj.str);
	}
}