NSURLSession category bug

gistfile1.m

#import <Foundation/Foundation.h>

@interface NSURLSession (Stuff)
-(void)doStuff;
@end

@implementation NSURLSession (Stuff)
-(void)doStuff {
    NSLog(@"stuff");
}
@end

int main(int argc, char *argv[]) {
	@autoreleasepool {
	    NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration];
	    NSURLSession *session = [NSURLSession sessionWithConfiguration:config delegate:nil delegateQueue:nil];
	    if ([session isKindOfClass:[NSURLSession class]]) {
	        NSLog(@"YES");
	    }
	    else {
		NSLog(@"NO");
	    }
	    [session doStuff];
	}
}