Re: [PATCH 07/11] mfd: Drop unnecessary static

Julia Lawall
2017-07-15T20:56:05Z

On Sat, 15 Jul 2017, Mark D Rustad wrote:

> > On Jul 15, 2017, at 1:07 PM, Julia Lawall <Julia.Lawall@lip6.fr> wrote:
> >
> > Drop static on a local variable, when the variable is initialized before
> > any possible use. Thus, the static has no benefit.
>
> I think in this case the use relies on the structure continuing to exist, so a stack object is not an acceptable substitute. Just because it is initialized doesn't mean that it doesn't need a persistent lifetime.

OK, I see. Thanks for the feedback. I'll extend the rule to ensure that
the address of the variable is not taken. Ignore this patch in any case.

julia

>
> > The semantic patch that fixes this problem is as follows:
> > (http://coccinelle.lip6.fr/)
> >
> > // <smpl>
> > @bad exists@
> > position p;
> > identifier x;
> > type T;
> > @@
> > static T x@p;
> > ...
> > x = <+...x...+>
> >
> > @@
> > identifier x;
> > expression e;
> > type T;
> > position p != bad.p;
> > @@
> > -static
> > T x@p;
> > ... when != x
> > when strict
> > ?x = e;
> > // </smpl>
> >
> > Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> >
> > ---
> > These patches are all independent of each other.
> >
> > drivers/mfd/twl4030-irq.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff -u -p a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
> > --- a/drivers/mfd/twl4030-irq.c
> > +++ b/drivers/mfd/twl4030-irq.c
> > @@ -685,7 +685,7 @@ int twl4030_sih_setup(struct device *dev
> >
> > int twl4030_init_irq(struct device *dev, int irq_num)
> > {
> > - static struct irq_chip twl4030_irq_chip;
> > + struct irq_chip twl4030_irq_chip;
> > int status, i;
> > int irq_base, irq_end, nr_irqs;
> > struct device_node *node = dev->of_node;
>
> --
> Mark Rustad, MRustad@gmail.com
>
>