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    SubjectRe: [RFC 01/32] fs: introduce new 'struct inode_time'
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    Hi Andreas,

    On Sat, May 31, 2014 at 10:39 AM, Andreas Schwab <schwab@linux-m68k.org> wrote:
    > Geert Uytterhoeven <geert@linux-m68k.org> writes:
    >
    >> Hi Arnd,
    >>
    >> On Fri, May 30, 2014 at 10:01 PM, Arnd Bergmann <arnd@arndb.de> wrote:
    >>> + * The variant using bit fields is less efficient to access, but
    >>> + * small and has a wider range as the 32-bit one, plus it keeps
    >>> + * the signedness of the original timespec.
    >>> + */
    >>> +struct inode_time {
    >>> + long long tv_sec : 34;
    >>> + int tv_nsec : 30;
    >>> +};
    >>
    >> Don't you need 31 bits for tv_nsec, to accommodate for the sign bit?
    >> I know you won't really store negative numbers there, but storing a large
    >> positive number will become negative on read out, won't it?
    >
    > Only if the int bitfield is signed. Bitfields are weird, aren't they? :-)

    "int" is signed, right? Or do you mean a bitfield needs an explicit "signed"
    keyword to be signed?

    Gr{oetje,eeting}s,

    Geert

    --
    Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

    In personal conversations with technical people, I call myself a hacker. But
    when I'm talking to journalists I just say "programmer" or something like that.
    -- Linus Torvalds


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