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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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