Is this a problem of 'SizeOf' or of the debugger?

[Dany]

Hi, the SizeOf(MyRec) gives 20, while the size is obviously only 18 (including the alignment dummy bytes). Are the 2 extra bytes something related to the variable alignment issue (I would myself prefer that the value 18 is given back by the function SizeOf, of course the dummy bytes inserted for alignment have to be counted as they are now).

Thanks in advance.

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The code is the following:

Code: Select all

program Word_Alignment;

{ Declarations section }

Type TArr = Array[5] of byte;

Type Trec = record
    Byte1: byte;
    Word1: word;
    Byte2: byte;
    Dword1: dword;
    Byte3: byte;
    Arr1: TArr;
    end;

var MyRec: TRec;  volatile;
    Siz: byte;

begin
  { Main program }
  Siz := SizeOf(MyRec);
end.

[filip]

Hi Dany,

I see your point, I will consult our developers and get back to you ASAP.

Thanks for the patience.

EDIT:
This is due to the variable alignment, from the help file :

Simple type variables whose size is 2 bytes are set to alignemnt 2, those whose size is 4 bytes and larger are set to alignment 4. Variables of other size are set to alignment 1.
Routines are always set to alignment 4. Only aligned memory access is supported.

Regards,
Filip.

[Dany]

Hi Dany,

This is due to the variable alignment, from the help file :

Simple type variables whose size is 2 bytes are set to alignemnt 2, those whose size is 4 bytes and larger are set to alignment 4. Variables of other size are set to alignment 1.
Routines are always set to alignment 4. Only aligned memory access is supported.

Regards,
Filip.

Indeed, all is clear now. Thanks very much.