Re: Memeory management

[tmoran@acm.org]

>wonder that are there any constrains on the memory allocated for
>variable declaraions? However, I did not allocate and deallocate memory
>as I did in C, does Ada provide automatically garbage collection?
  A particular Ada compiler, with a particular set of compile options,
and a particular OS, and a particular target machine, will of course
have some particular memory limitation.  How much memory do you need?
  If you declare variables in the ordinary way, e.g.
    procedure P(N : Positive) is
      Vector : array(1 .. N) of Integer;
      Bigger_Vector : array(1 .. 5*N) of Integer;
      Var1, Var2 : Float;
    begin
Ada will automatically allocate space for Vector, Bigger_Vector, Var1, and
Var2 at the beginning and deallocate on exit.
  If you allocate explicitly from the heap using access types (pointers)
and "new" then the Ada specification does not say whether the
implementation must do automatic garbage collection or not.  Most don't,
so you would need to explicitly use Ada.Unchecked_Deallocation to do your
deallocations.  (Many Ada applications are real time and it would be be
Bad if your train control program started doing extensive garbage
collection just when a sensor detected an obstacle on the track.)