Re: [PATCH 1/2] linux/kernel.h: use 'short' to define USHRT_MAX, SHRT_MAX, SHRT_MIN

[Masahiro Yamada]

On Sun, Feb 3, 2019 at 1:33 AM Alexey Dobriyan <adobriyan@xxxxxxxxx> wrote:
>
> On Sun, Feb 03, 2019 at 01:06:24AM +0900, Masahiro Yamada wrote:
> > The log of commit 44f564a4bf6a ("ipc: add definitions of USHORT_MAX
> > and others") did not explain why it used (s16) and (u16) instead of
> > (short) and (unsigned short).
> >
> > Let's use (short) and (unsigned short), which is more sensible, and
> > more consistent with the other MAX/MIN defines.
> >
> > As you see in include/uapi/asm-generic/int-ll64.h, s16/u16 are
> > typedef'ed as signed/unsigned short. So, this commit does not have
> > a functional change.
>
> > -#define USHRT_MAX    ((u16)(~0U))
> > -#define SHRT_MAX     ((s16)(USHRT_MAX>>1))
> > -#define SHRT_MIN     ((s16)(-SHRT_MAX - 1))
> > +#define USHRT_MAX    ((unsigned short)(~0U))
>                                          ^   ^
>                                          +---+
>                                            unnecessary ()


Thanks, I will remove it in v2.




> > +#define SHRT_MAX     ((short)(USHRT_MAX>>1))
> > +#define SHRT_MIN     ((short)(-SHRT_MAX - 1))
>
> "short" and "unsigned short" are probably the most useless C types.
> I doubt their usage should be promoted.



-- 
Best Regards
Masahiro Yamada