[rtems commit] Use uint32_t instead of long. Use unsigned defines ( Prevent overflows on 16bit targets)

[Gedare Bloom]

On Wed, Apr 17, 2013 at 11:15 AM, Ralf Corsepius
<ralf.corsepius at rtems.org> wrote:
> On 04/17/2013 02:53 PM, Sebastian Huber wrote:
>>
>> On 04/17/2013 12:19 PM, Ralf Corsepius wrote:
>> [...]
>>>
>>> @@ -147,8 +147,8 @@ static uint32_t simple_random(uint32_t v)
>>>
>>>   static unsigned get_bucket_with_random(unsigned count, long random)
>>>   {
>>> -  long unsigned unit = (1U << 31) / count;
>>> -  long unsigned bucket = (long unsigned) random / unit;
>>> +  uint32_t unit = ((uint32_t) 1U << 31) / count;
>>> +  uint32_t bucket = (uint32_t) random / unit;
>>>
>>>     if (bucket != count) {
>>>       return bucket;
>>
>>
>> A long must be able to store a 32-bit integer so there is no need to use
>> uint32_t here.
>
>
> Such is theory - Realty is different.
>
> The assumptions of long >= 32 bit only applies to POSIX conformant targets.
>
> RTEMS however supports targets, which are not strictly POSIX compliant,
> where longs are 16bit => The code above fails to compile the code above when
> using longs.
>
I'm pretty sure the minimum width of long is 32 bits in standard C,
nothing to do with POSIX. If you can cite a counter-example, fine.
Anyway, it doesn't make much difference here whether long or uint32 is
used.

>
> Ralf
>
>
>
>
>
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