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From: "Vinzent Hoefler" <0439279208b62c95f1880bf0f8776eeb@t-domaingrabbing.de>
Newsgroups: comp.lang.ada
Subject: Re: Large arrays passed to arithmetic operators overflows GNAT stack
Date: Sat, 04 Dec 2010 10:19:47 +0100
Message-ID: <op.vm6mu9ojlzeukk@jellix.jlfencey.com>
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Date: 2010-12-04T10:19:47+01:00
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Jerry wrote:

> with
>     Ada.Numerics.Long_Real_Arrays;
> use
>     Ada.Numerics.Long_Real_Arrays;
> procedure array_test is
>     type Real_Vector_Access    is access Real_Vector;
>     N : Integer := 1_048_130;
[...]
> begin
>     for i in t'range loop
>         t(i) := 1.0;
>     end loop;
>     t_Diff := t(1 .. N) - t(0 .. N - 1);
> end array_test;

It's probably not the operator call that crashes, but the creation of
the temporary arrays t(...). Couple of days ago, I stumbled upon a
similar problem with aggegrate assignments:

    --  Do array initialization in a loop.
    --  If it's done with an aggregate assignment, GNAT raises Storage_Error
    --  during elaboration.

> Another fix would be to write operator procedures that specifically
> take pointers as arguments; that would possibly be the only fix for
> arrays that still overflow the stack when it is maxed out.

This wouldn't help here, I suppose.


Vinzent.

-- 
Beaten by the odds since 1974.