On Sun, Oct 7, 2018 at 6:58 AM Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> wrote: > > Hi Miguel, > > > On Sun, Oct 7, 2018 at 6:18 AM Miguel Ojeda > <miguel.ojeda.sandonis@xxxxxxxxx> wrote: > > > > On Fri, Oct 5, 2018 at 10:35 AM Arnd Bergmann <arnd@xxxxxxxx> wrote: > > > > > > Building any configuration with 'make W=1' produces a warning: > > > > > > kernel/bounds.c:16:6: warnign: no previous prototype for 'foo' [-Wmissing-prototypes] > > > > > > When also passing -Werror, this prevents us from building any > > > other files. Nobody ever calls the function, but we can't make > > > it 'static' either since we want the compiler output. > > > > > > Calling it 'main' instead however avoids the warning, because gcc > > > does not insist on having a declaration for main. > > > > I think marking the function as static __used should do the trick and > > would be less confusing. > > > > > I tried __used, but I still see the warning. > > > masahiro@grover:~/ref/linux$ git diff > diff --git a/kernel/bounds.c b/kernel/bounds.c > index c373e88..aee0101 100644 > --- a/kernel/bounds.c > +++ b/kernel/bounds.c > @@ -13,7 +13,7 @@ > #include <linux/log2.h> > #include <linux/spinlock_types.h> > > -void foo(void) > +void __used foo(void) > { > /* The enum constants to put into include/generated/bounds.h */ > DEFINE(NR_PAGEFLAGS, __NR_PAGEFLAGS); > masahiro@grover:~/ref/linux$ make W=1 prepare > CC kernel/bounds.s > kernel/bounds.c:16:13: warning: no previous prototype for ‘foo’ > [-Wmissing-prototypes] > void __used foo(void) > ^ > CC arch/x86/kernel/asm-offsets.s Sorry, I forgot to add 'static'. Adding both static and __used worked for me, and I like the idea. -- Best Regards Masahiro Yamada