[Tinyos Core WG] proposal for some (small) changes in the core

[Philip Levis]

On May 27, 2008, at 11:25 AM, David Gay wrote:

> On Tue, May 27, 2008 at 10:36 AM, Philip Levis <pal at cs.stanford.edu>  
> wrote:
>>
>> On May 27, 2008, at 9:57 AM, Jan Hauer wrote:
>>
>>>
>>> (*) There is problem with tos/lib/timer/VirtualizeAlarmC.nc on  
>>> msp430:
>>> with mspgcc-3.2.3 I get a "Segmentation fault" during compilation  
>>> if I
>>> use uint32_t as "size_type", e.g. "VirtualizeAlarmC(T32khz,  
>>> uint32_t,
>>> uniqueCount(UQ_ALARM_32KHZ32));". The probelm is in line 135 of
>>> VirtualizeAlarmC. Currently lines 134-136 read:
>>>
>>> if( m.isset[id] ) {
>>> size_type elapsed = call AlarmFrom.getNow() - m.alarm[id].t0;
>>> if( m.alarm[id].dt <= elapsed ) {
>>>
>>> I don't understand the actual cause, but when I replace this with  
>>> the
>>> following code it compiles:
>>>
>>> if( m.isset[id] ) {
>>> size_type t0 = m.alarm[id].t0;
>>> size_type elapsed = call AlarmFrom.getNow() - t0;
>>>  if( m.alarm[id].dt <= elapsed ) {
>>>
>>> This fix should not have any impacts for other platforms, so I  
>>> suggest
>>> to use it as a workaround.
>>
>> These kinds of things are the reason why we settled on a version of
>> gcc for the avr and msp430 rather than follow the head. Continually
>> tweaking source to avoid bugs, and asking people to update their
>> compiler often to keep up, is just not feasible.
>
> isn't the one he's using (3.2.3) the one we settled on for msp430,  
> though? ;-)

Yes -- my point is that we can of course fix this, but imagine if  
churn on the compiler caused which lines of code cause problems to  
change regularly...

Phil