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

[Harald Kipp]

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);

Regards,

Harald