NSJSONSerialization EXC_BAD_ACCESS KERN_INVALID_ADDRESS

example.m

+ (void)load {
    static NSMutableDictionary *myMutableDict;
    static NSDictionary *myDict;

    myMutableDict = [NSMutableDictionary dictionaryWithDictionary:@{}];
    myDict = @{@"sub_dict" : myMutableDict};

    /* Hop on a background thread */
    dispatch_async(dispatch_get_global_queue(0, 0), ^{
        /* Constantly mutate the mutable dictionary */
        while (YES) {
            [myMutableDict setObject:[[NSUUID UUID] UUIDString] forKey:[[NSUUID UUID] UUIDString]];
        }
    });

    while (YES) {
        /* Constantly try serializing the non-mutable outer dictionary */
        /* This line will eventually result in EXC_BAD_ACCESS KERN_INVALID_ADDRESS */
        NSData * __unused data = [NSJSONSerialization dataWithJSONObject:myDict options:kNilOptions error:nil];
    }
}