On Mon, Mar 22, 2021 at 05:34:48PM +0100, Arnd Bergmann wrote: > 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. I agree that if it's only 26 patches on the whole kernel to re-enable one warning it can be worth it for newcomers. Willy