Re: [PATCH v3 2/4] vhost-vdpa: introduce STOP backend feature bit

[Eugenio Perez Martin <eperezma@redhat.com>]

On Thu, May 26, 2022 at 9:07 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> On Thu, May 26, 2022 at 07:00:06PM +0200, Eugenio Perez Martin wrote:
> > > It feels like returning any literal that isn't 1 or 0 should trigger a
> > > warning...  I've written that and will check it out tonight.
> > >
> >
> > I'm not sure this should be so strict, or "literal" does not include pointers?
> >
>
> What I mean in exact terms, is that if you're returning a known value
> and the function returns bool then the known value should be 0 or 1.
> Don't "return 3;".  This new warning will complain if you return a known
> pointer as in "return &a;".  It won't complain if you return an
> unknown pointer "return p;".
>

Ok, thanks for the clarification.

> > As an experiment, can Smatch be used to count how many times a
> > returned pointer is converted to int / bool before returning vs not
> > converted?
>
> I'm not super excited to write that code...  :/
>

Sure, I understand. I meant if it was possible or if that is too far
beyond its scope.

> >
> > I find Smatch interesting, especially when switching between projects
> > frequently. Does it support changing the code like clang-format? To
> > offload cognitive load to tools is usually good :).
>
> No.  Coccinelle does that really well though.
>

Understood.

Thanks!

> regards,
> dan carpenter
>