Re: [PATCH] staging: comedi: remove __user annotation inside of struct's

Dan Carpenter
2012-05-09T14:16:33Z

On Wed, May 09, 2012 at 12:01:25PM +0100, Ian Abbott wrote:
> Are there any handy macros for casting pointers to __user pointers,
> something like
>
> #define _user(p) ((typeof(*(p)) __user *)(p))
>
> but preferably without the repeated expansion of 'p' in case of
> side-effects?

typeof() doesn't have side effects.

#include <stdio.h>

int main(void)
{
int x = 0;
typeof(x++) y;

printf("%d\n", x);

return 0;
}

regards,
dan carpenter