Re: Record -> Array in Ada

[dmarshal@netcom.com (Dave Marshall)]

Mike Roske <mroske@mailgw.sanders.lockheed.com> writes:

[snipped the introduction: need to transmit a record as a number of
16-bit values.]

>I have identified the following options:

>1) Unchecked_Conversion into a fixed size array.  (And if I do this, how
>do I get the array bounds set correctly?)

I've done this rather frequently.  The number of words is computed
thusly, use whatever stylistics you like:

Number_Of_Words : constant := (My_Record_Type'Size + 15) / 16;

>2) Pass Record'Address and Record'Size into a subprogram.  Inside the
>subprogram, declare an array of the appropriate size, located at the
>appropriate address.  (have prototyped this one, and it works.)

*FROWNERZ*, sometimes we are prevented from doing the cool things that
work.  LRM 13.5(8):

"Address clauses should not be used to achieve overlays of objects or
overlays or program units.  Nor should a given interrupt be linked to
more than one entry.  Any program using address clauses to achieve
such effects is erroneous."

-- 
Dave Marshall
dmarshal@netcom.com