[fpc-devel] bug: Inc(v,i)/Dec(v,i)

[C Western]

Marco van de Voort wrote:
>>>>var
>>>>  v : cardinal;
>>>>begin
>>>>  v:=100;
>>>>  inc(v,-1);
>>>>end.
>>>>
>>>>The reason is that -1 is in fact an addition of $ffffffff resulting in the
>>>>carry flag being set and therefor an overflow.
>>>
>>>For cardinal IMHO not-a-bug?
>>
>>I think it's a bug for cardinals and other unsigned ints also (as long as the
>>result is in the range of the result variable)
> 
> 
> -1 is not a valid cardinal -> out of range -> rangecheck error.
> 
But on the other hand Dec(v,1) is fine, so Inc(v,-1) should also work.
Colin