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    SubjectRe: [PATCH] Introduce nodemask_t ADT [0/7]
    On Mon, Mar 22, 2004 at 06:39:18PM -0800, Paul Jackson wrote:
    > From this I conjecture that I can provide a single call:
    > cpumask_and(cpumask_t d, cpumask_t s1, cpumask_t s2);
    > that works on both normal (1 to 32 cpu) systems and on big iron systems,
    > with traditional 'C' pass by value semantics, all derived from a single
    > mask type that works for both node and cpu masks.
    > The one sticky point evident to me so far would be if some generic code
    > were passing a cpumask_t across a function call boundary, and needed to
    > be optimum for both small and sparc64 - one would want to pass by value,
    > the other would want to pass a pointer to the cpumask.
    > This is not your fathers 'C'. The compile time inlining and
    > optimization provided by gcc enables it to do a lot more than Dennis
    > Ritchie's original C compiler that I learned on.

    gcc flat out miscompiled such inlines last I checked (Zwane shipped the
    bugreport IIRC). Either this kind of good behavior is not universally
    observable or a miracle occurred and gcc's codegen went from incorrect
    to 1980's (fscking patents).

    Anyhow, this was also an observation of the code effectively made in
    isolation; uninlining and other catastrophes do happen.

    If people really thinks this works and/or don't care when it doesn't,
    go for it. Last time I heard they did; who knows, the answer may be
    different this time.


    -- wli
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