Hi,

I think I found a bug with bitpackeds records.

I have the next record.

   TBitpacked = packed record
     Case Integer Of
       0 : (Word :  Word);
       1 : (Byte :  array [0..1] of Byte);
       2 : (Boolean: bitpacked Array [0..15] of boolean);
       3 : (Bit : bitpacked Record
           case integer of
             0: (bit0: Boolean);
             1: (bit1: Boolean);
             2: (bit2: Boolean);
             3: (bit3: Boolean);
             4: (bit4: Boolean);
             5: (bit5: Boolean);
             6: (bit6: Boolean);
             7: (bit7: Boolean);
             8: (bit8: Boolean);
             9: (bit9: Boolean);
             10: (bit10: Boolean);
             11: (bit11: Boolean);
             12: (bit12: Boolean);
             13: (bit13: Boolean);
             14: (bit14: Boolean);
             15: (bit15: Boolean);
           end);
     end;

See the program below.

var
   pp:TBitpacked;
begin
   pp.Word:=0;
   pp.Boolean[1]:=true;
   writeln(pp.Byte[0]); // This prints 2 -- OK
   writeln(pp.Boolean[0]); // This prints False -- OK
   writeln(pp.Boolean[1]); // This prints True -- OK
   pp.Word:=0;
   pp.Bit.bit1:=true;
   writeln(pp.Byte[0]); // This prints 1 -- WRONG
   writeln(pp.Boolean[0]); // This prints True -- WRONG
   writeln(pp.Boolean[1]); // This prints False -- WRONG
   pp.Word:=0;
   pp.Boolean[8]:=true;
   writeln(pp.Byte[0]); // This prints 0 -- OK
   writeln(pp.Byte[1]); // This prints 1 -- OK
   writeln(pp.Boolean[0]); // This prints False -- OK
   writeln(pp.Boolean[8]); // This prints True -- OK
   pp.Word:=0;
   pp.Bit.bit8:=true;
   writeln(pp.Byte[0]); // This prints 1 -- WRONG
   writeln(pp.Byte[1]); // This prints 0 -- WRONG
   writeln(pp.Boolean[0]); // This prints True -- WRONG
   writeln(pp.Boolean[8]); // This prints False -- WRONG
end.

Is this a known issue or there is something wrong with my code?

I tested this with FPC 3.0.4 and trunk, same result.

Best Regards.

El 12/5/19 a les 17:58, Victor Campillo ha escrit:

With that last case, aren't you just defining one bit in the bitpacked record?
In that case

this would be correct.

Bye

With this layout bit0 to bit15 will all point to bit0. You probably didn't mean to do the case inside the bitpacked record

Jeppe Johansen wrote

With this layout bit0 to bit15 will all point to bit0. You probably didn't mean to do the case inside the bitpacked record

Yes, you are right, I don't want the case there, copy/paste error.

One hour looking that record declaration and I could not point out that mistake, time to left the laptop and grab a beer :)

Thank you Jeppe.

Best Regards.

Luca Olivetti wrote

With that last case, aren't you just defining one bit in the bitpacked record? In that case

Thanks Luca, the case was the problem, I wanted a bitpacked record of
word, this was a silly copy / paste error.