[fpc-devel] concernig Bug Id 4145: Request for Bit-level packing in MacPas mode

[Adriaan van Os]

Jonas Maebe wrote:

> Gerhard Scholz wrote:
>
>> if really someone does this, it would be nice to have it in 
>> "standard" (FPC)
>> mode also.
>
> You will be able to activate it with a preprocessor switch.
>
>> not just packed records, but also packed arrays:
>>
>> packed array [ 1..2 ] of 0..15 { one byte }
>>
>> packed array [ 1..8 ] of boolean { one byte }
>
> The implementation of that would be completely separate from the 
> support required for records. Also, since that is not required for 
> compatibility, that will have a lower priority (unless someone submits 
> a clean patch for it, of course)

I am not trying to say that bit-level packing should have high priority 
(there are ways to work around it) but, since you mention 
compatibility, I would like to note that bit-level packed arrays are 
indeed a feature of UCSD, MPW, Think, MetroWerks, and GNU Pascal.

Another issue that comes to my mind is passing components of packed 
structures as actual variable parameters. Standard Pascal doesn't allow 
it at all, but it is more practical to forbid it only if the packed 
component uses bit-packing.

Regards,

Adriaan van Os