Maybe Array Length is Negative (MALN)

Description:

MALN detects if the range of the length expression of the created array may contain negative values, so it is possible that the length of the created array will be negative. It will not report this message if the minimum value of the length is less than -127 (to avoid messages for all expressions of sign types).

Incorrect:

type
  chars = array of char;
...
function create(len:integer):chars;
begin
    if len >= 0 then
        SetLength(result,len-1);
end;