ARC Retain Cycle appears after updating to iOS 6.1

Question

After updating to iOS 6.1, I'm getting this warning in AFImageRequestOperation.m and AFHTTPClient.m from AFNetworking framework:

Capturing 'operation' strongly in this block is likely to lead to a retain cycle

Based on this answer, I can fix a retain cycle in ARC by using __weak variables. It is also says

Block will be retained by the captured object

Does anyone know how to solve this?

Thanks.

Answer 1

We are fortunate that XCode 4.6 is showing a warning to avoid this problem It can be solved by providing a weak reference

AFImageRequestOperation *requestOperation = [[AFImageRequestOperation alloc] initWithRequest:urlRequest];

**__weak AFImageRequestOperation *tempRequestOperation = requestOperation;**

[requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
    if (success) {
        UIImage *image = responseObject;
        if (imageProcessingBlock) {
            dispatch_async(image_request_operation_processing_queue(), ^(void) {
                UIImage *processedImage = imageProcessingBlock(image);

                dispatch_async(**tempRequestOperation**.successCallbackQueue ?: dispatch_get_main_queue(), ^(void) {
                    success(operation.request, operation.response, processedImage);
                });
            });
        } else {
            success(operation.request, operation.response, image);
        }
    }
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    if (failure) {
        failure(operation.request, operation.response, error);
    }
}];