Re: error in index constraints with initial value

["Frank J. Lhota" <NOSPAM.lhota.adarose@verizon.net>]

The problem with your definition of XXXX_LINE is that you do not constrain
the record variant LENGTH. LENGTH will default to 5, but since it is not
constrained, XXXX_LINE can be assigned a VAR_LINE value of any length, even
LENGTH => Integer'Last! Of course, this requires more space than is
possible, resulting in the blow-up.

There are a couple of ways to handle this properly. If XXXX_LINE really
needs to hold VAR_LINE records of widely varying and arbitrarily long
lengths, you should declare XXXX_LINE as an access value and allocate these
VAR_LINE records from the heap.

Another possible solution is available is we can assume that there is a
reasonable upper limit on the length of a VAR_LINE. We can then use a
subtype to limit the value of LENGTH, so that VAR_LINE has a reasonable
maximum size, e.g.,

    subtype Var_Line_Len is Integer range 0 .. 1023;
    type VAR_LINE( LENGTH : Var_Line_Len := 5 ) is
    record
       IMM:STRING(1..LENGTH);
    end record;

With this declaration, VAR_LINE will never have a length greater than
Var_Line_Len'Last. With this change, your program should compile.