On Mon, Mar 22, 2021 at 5:26 PM Willy Tarreau <w@xxxxxx> wrote:
> On Mon, Mar 22, 2021 at 05:18:23PM +0100, Arnd Bergmann wrote:
> > and a lot mostly harmless code like
> >
> > #ifdef DEBUG_THIS_DRIVER /* always disabled */
> > #define dprintk(args...) printk(args)
> > #else
> > #define dprintk(args...)
> > #endif
> > /* note the mismatched format string */
> > dprintk(KERN_WARNING "error %d\n", &object);
> >
> > Turning the empty dprintk() into no_printk() means we can catch
> > the wrong format string during compile testing.
>
> Hmmm OK for this one. With this said, given how plenty of warnings seem
> to consider indent and whatever, I wouldn't be surprised if a difference
> is made between a totally empty body and one that results from an empty
> macro. But indeed this one can represent a real bug.
The -Wempty-body warning is actually really old and predates the compiler's
understanding of indentation, we just always disabled it by default so far.
As a lot of subsystems are W=1 clean these days, I just went for the
final 26 patches to shut up all empty-body warnings in randconfig builds.
Most of these were in the dprink() category, though none of this last set
actually had incorrect format strings.
Arnd
