Re: [patch] samples/bpf: silence shift wrapping warning

Alexei Starovoitov
2017-01-22T22:51:25Z

On Sat, Jan 21, 2017 at 07:51:43AM +0300, Dan Carpenter wrote:
> max_key is a value in the 0-63 range, so on 32 bit systems the shift
> could wrap.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Looks fine. I think 'net-next' is ok.

Acked-by: Alexei Starovoitov <ast@kernel.org>

> diff --git a/samples/bpf/lwt_len_hist_user.c b/samples/bpf/lwt_len_hist_user.c
> index ec8f3bb..bd06eef 100644
> --- a/samples/bpf/lwt_len_hist_user.c
> +++ b/samples/bpf/lwt_len_hist_user.c
> @@ -68,7 +68,7 @@ int main(int argc, char **argv)
> for (i = 1; i <= max_key + 1; i++) {
> stars(starstr, data[i - 1], max_value, MAX_STARS);
> printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
> - (1l << i) >> 1, (1l << i) - 1, data[i - 1],
> + (1ULL << i) >> 1, (1ULL << i) - 1, data[i - 1],
> MAX_STARS, starstr);
> }
>