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    SubjectRe: {put,get}_user() side effects
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    > On Tue, 2004-04-06 at 13:32 +0200, Andi Kleen wrote:
    > > Geert Uytterhoeven <geert@linux-m68k.org> writes:
    > >
    > > > On most (all?) architectures {get,put}_user() has side effects:
    > > >
    > > > #define put_user(x,ptr) \
    > > > __put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
    > >
    > > Neither typeof not sizeof are supposed to have side effects. If your
    > > compiler generates them that's a compiler bug.
    >
    > Using ptr three times in a define has side effects if ptr is an
    > expression with side effects (e.g. "p++").

    Sorry, I read too fast. I didn't know sizeof could avoid side effects.

    Xav

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