Re: A simple question about the "new" allocator

[Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>]

On 08/11/2014 11:54 PM, NiGHTS wrote:
> With all default configurations using a typical Ada compiler, will the
> following code run indefinitely without fail or will it eventually crash?

With a typical Ada compiler, your program will crash. Ada's definition allows 
garbage collection but doesn't require it. I'm not aware of any compiler that 
implements it.

> If this does crash, what would be another way to write this program so that
> it does not crash? I would prefer not to use Ada.Unchecked_Deallocation.

If it didn't crash, your program would run forever without any visible effect; 
it's quite easy to write such a program. Presuming that's not what you're 
asking, you can repeatedly allocate memory using a safe pointer without running 
out of memory:

with PragmARC.Safe_Pointers;

procedure Does_Not_Crash is
    package Positive_Pointers is new PragmARC.Safe_Pointers (Object => Positive);

    Test : Positive_Pointers.Safe_Pointer;
begin -- Does_Not_Crash
    loop
       Test := Positive_Pointers.Allocate;
    end loop;
end Does_Not_Crash;

-- 
Jeff Carter
"There's no messiah here. There's a mess all right, but no messiah."
Monty Python's Life of Brian
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