Re: Allocating Memory with "new"

["David C. Hoos" <david.c.hoos.sr@ada95.com>]

----- Original Message -----
From: "Peter Richtmyer" <prichtmyer@yahoo.com>
Newsgroups: comp.lang.ada
To: <comp.lang.ada@ada.eu.org>
Sent: Friday, April 25, 2003 5:33 AM
Subject: Re: Allocating Memory with "new"


> "Vincent Smeets" <No.Spam@localhost> wrote in message
news:<3ea8d041$0$4083$4d4ebb8e@read.news.de.uu.net>...
>
> > Every time an access type comes out of scope, the memory allocated by
that
> > access type can be freed (garbage collection).
>
> Thanks - that certainly explains it. I thought the programmer had
> complete control of the memory allocated and that it would not be
> freed until an Unchecked Deallocate (or the program ended).
>
>From the addresses allocated, it looks like the allocation was done on the
stack, instead of the heap.  The compiler is free to do this, given that
Mem_Block_Ptr is declared on the stack.

Thus, this is not "garbage collection," but simply the fact that the
allocated memory goes out of scope when the procedure returns.

In this sense, the Rational compiler is "smarter" than GNAT, since
allocation on the heap is more expensive than allocation on the stack.

Incidentally, setting Mem_Block_Ptr to null is unnecessary, since
the rules of Ada require access objects to be initialized to null.

David