Subject: Re: 2.6.22-rc2 built on ppc

From: Stefan Richter <[email-masked]>
Date: Sun, 20 May 2007 18:01:48 +0200

I wrote:
> The allegedly unused variables are used in calls to dma_unmap_single(),
> but only for these calls.

and a call to dma_unmap_sg().

> On PPC32, you get
> 
> 	/* We do nothing. */
> 	#define dma_unmap_single(dev, addr, size, dir)  ((void)0)
> 
> in dma-mapping.h.  This is also the case for Linux 2.6.20.
> But in Linux 2.6.19 and older, it was
> 
> 	/* We do nothing. */
> 	#define dma_unmap_single(dev, addr, size, dir)	do { } while (0)
...
> I don't know what's to blame for the warnings --- new gcc versions or
> the change from do { } while (0) to ((void)0)?
...

Ditto for dma_unmap_sg().
-- 
Stefan Richter
-=====-=-=== -=-= =-=--
http://arcgraph.de/sr/