[PATCH v3 1/4] net/macb: fix truncate warnings

On Tue, Oct 23, 2012 at 2:00 PM, Lothar Wa?mann [off-list ref] wrote:

Hi,

David Miller writes:

quoted

From: "David Laight" <redacted>
Date: Tue, 23 Oct 2012 09:21:11 +0100

quoted

quoted

When building macb on x86_64 the following warnings show up:
  drivers/net/ethernet/cadence/macb.c: In function macb_interrupt:
  drivers/net/ethernet/cadence/macb.c:556:4: warning: large integer implicitly truncated to unsigned type [-Woverflow]

...

quoted

-                  macb_writel(bp, IDR, ~0UL);
+                  macb_writel(bp, IDR, -1);

Seems wrong to fix an error with an unsigned value
by using -1.

-1 is equally an unsigned value of all 1's and completely legitimate.
The correction being made here is one of size not signedness.

You could use '~0' (without the 'UL').

The reason for choosing '-1', as noted in patch description, is that
it already appears in a couple of other places in the driver. So I
though it would nice to be consistent.

regards
Joachim Eastwood