Re: [PATCH 0/9] QEMU file cleanups

[Juan Quintela]

Peter Xu <peterx@redhat.com> wrote:
> On Thu, May 04, 2023 at 01:38:32PM +0200, Juan Quintela wrote:
>> - convince and review code to see that everything is uint64_t.
>
> One general question to patches regarding this - what's the major benefit
> of using uint64_t?
>
> It doubles the possible numbers to hold, but it's already 64bits so I don't
> think it matters a lot.

We were checking for negatives even when that can't be.
And we are doing this dance of

int64_t x, y;
uint64_t a, b;

x = a;
b = y;

This is always confusing and not always right.

> The thing is we're removing some code trying to
> detect negative which seems to be still helpful to detect e.g. overflows
> (even though I don't think it'll happen).  I just still think it's good to
> know when overflow happens, and not sure what I missed on benefits of using
> unsigned here.

If you grep through the code, you see that half of the things are
int64_t and the other half is uint64_t.  I find it always confusing.


> I've reviewed all the rest patches and all look good here.

Thanks very much.