[En-Nut-Discussion] Hardware Register Access Using Volatile Pointer

[Bernd Walter]

On Tue, Apr 26, 2011 at 09:33:26AM +0200, Harald Kipp wrote:
> Hi Ulrich,
> 
> On 4/25/2011 11:44 PM, Ulrich Prinz wrote:
> >>
> >> PS: reading into a dummy variable won't help, since the compiler is
> >> free to optimze dummy (and even real) variable away.
> >>
> > In addition newer versions of gcc will throw a warning "Variable
> > declared and set is not evaluated" or something similar.
> 
> That's the origin of the problem. Michael Fischer asked me to fix a few 
> warnings when compiling the trunk with GCC 4.6. It turned out to become 
> a bit more difficult than expected. The first warning appeared at 
> arch/arm/dev/ostimer_at91.c:
> 
> int dummy;
> ...
> dummy = inr(TC0_SR);

(void) dummy;

-- 
B.Walter <bernd at bwct.de> http://www.bwct.de
Modbus/TCP Ethernet I/O Baugruppen, ARM basierte FreeBSD Rechner uvm.