[lkml]   [2008]   [Dec]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [patch] powerpc: change u64/s64 to a long long integer type
    On Tue, 23 Dec 2008 00:00:35 +0100
    Sam Ravnborg <> wrote:

    > On Mon, Dec 22, 2008 at 02:43:19PM -0800, Andrew Morton wrote:
    > > On Mon, 22 Dec 2008 09:03:41 +0100
    > > Ingo Molnar <> wrote:
    > >
    > > > Subject: powerpc: change u64/s64 to a long long integer type
    > >
    > > <applause>
    > >
    > > There are lots of other architctures that need doing though.
    > I have missed the introduction.
    > Can you explain why?

    People keep on doing

    printk("%llu", some_u64);

    testing it only on x86_64 and this generates a warning storm on
    powerpc, sparc64, etc. Because they use `long', not `long long'.

    And not just a little bit - this bug gets repeated maybe ten times per
    week - it's insane.

    If we make all architectures use `long long' then the above code
    becomes correct and warning-free on all architectures.

    And we then get to remove all the open-coded (unsigned long long) casts
    which we added all over the tree (hundreds of them).

    > I have done a bit of sparc hacking lately and was wondering if
    > sparc needs something similar.
    > cd arch/sparc
    > git grep u64 | grep -v __u64 | wc -l
    > 448
    > [On the unified tree]

    Yes, quite a few 64-bit architectures are using `long' for their
    s64/u64 types. We should convert them all to `long long'.

    That's quite trivial to do, but it causes a lot of warnings due to code
    in arch-speciic files which does

    printk("%lu", some_u64);

    which will then generate a warning. Or an error if the archtiecture
    uses -Werror, which several do. So we need to simultaneously convert
    all those to %llu. (Or %Lu, which saves a byte :))

     \ /
      Last update: 2008-12-23 00:17    [W:0.030 / U:10.620 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site