lkml.org 
[lkml]   [2004]   [Apr]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: {put,get}_user() side effects
From
Date
> 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

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:02    [W:0.042 / U:1.328 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site