Re: [PATCH 06/23] refs: use `size_t` indexes when iterating over ref transaction updates

From: Michael Haggerty <mhagger@alum.mit.edu>
Date: May 18, 2017, 04:55 UTC
Message-ID: <d9831944-47e0-e886-60ce-e3db151340dd@alum.mit.edu>
In-Reply-To: <CAGZ79kYspKC=NZDp8q46KO2pGBfsAfK8A=2PRDb2O1swOLf6MQ@mail.gmail.com>

On 05/17/2017 06:59 PM, Stefan Beller wrote:

Show 9 quoted lines

> On Wed, May 17, 2017 at 5:05 AM, Michael Haggerty <mhagger@alum.mit.edu> wrote:
> 
> Now this would want to have some selling words for it?
> I do not see an advantage of this patch as-is.
> 
> I mean technically we don't need a sign, so we use that extra bit
> to be able to process transactions up to twice the size. But I doubt
> that is the real reason. I'll read on, maybe a later patch will explain
> why we do this here.

The reason to use `size_t` is not signedness but rather that it might be larger than `int` (e.g., 64 vs 32 bits), so you could theoretically get an integer overflow otherwise. It's unlikely here, because it would be hard to initiate an update of more than (2³¹-1) references in a single update, but it's good hygiene anyway.

I'll mention that in the commit message.

Michael