From: Phil Sutter
> Sent: 23 June 2016 18:34
>
> By directly comparing the value of both unsigned variables, casting to
> signed becomes unnecessary.
>
> This also fixes for compiling with older versions of gcc (at least
> <=3.4.6) which emit the following warning:
>
> | ifstat.c: In function `update_db':
> | ifstat.c:542: warning: comparison is always false due to limited range of
> data type
>
> Signed-off-by: Phil Sutter <[email protected]>
> ---
> misc/ifstat.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/misc/ifstat.c b/misc/ifstat.c
> index abbb4e732fcef..9a44da487599e 100644
> --- a/misc/ifstat.c
> +++ b/misc/ifstat.c
> @@ -539,7 +539,7 @@ static void update_db(int interval)
> int i;
>
> for (i = 0; i < MAXS; i++) {
> - if ((long)(h1->ival[i] - n->ival[i]) <
> 0) {
> + if (h1->ival[i] < n->ival[i]) {
> memset(n->ival, 0,
> sizeof(n->ival));
> break;
That isn't the same check.
The original code is using modulo arithmetic.
David