Re: question oh macros and gcc's intelligence

From: Al Viro
Date: Thu Mar 17 2011 - 05:06:55 EST


On Thu, Mar 17, 2011 at 08:48:57AM +0100, Oliver Neukum wrote:
> Hi,
>
> if I write:
>
> if (le16_to_cpu(p) == CONST) a();
>
> is gcc smart enough to convert CONST to le16 and do
> a simple comparison?

On little-endian - certainly, on big-endian - forget it.
if (p == cpu_to_le16(CONST))
would obviously work on any architecture and yes, it would be a comparison
with compile-time constant.
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