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From: anon on 24 Jun 2008 19:36
0 - 1023MB 16-bit works -- 2GB

but in Ada: Integers are 4 bytes

0 - 1023MB 32-bit words -- 4GB

So:

1024MB 16-bit elements would be (2GB+1 (16-bit words))

but

1024MB 32-bit elements aka 1024MB Integer would be
(4GB+1 (32-bit words)) -- STORAGE_ERROR

so it seam that you did get the full 4GB RAM memory.


But the statement

Generic_Vector.Append (Evil_Vector, Integer'Last);

will create a vector size of 4GB with each element being 4 bytes
giving a total size of 16GB.

So, use:

Generic_Vector.Append ( Evil_Vector, ( Natural'Last / 4 ) ) ;

or better yet

Generic_Vector.Append ( Evil_Vector, ( Natural'Last / Natural'Size ) ) ;


to give you a 1GB Vector size with an 4 byte element size that uses
a total size of 4GB.


In <iVe8k.138597$SV4.76767(a)bgtnsc04-news.ops.worldnet.att.net>, anon(a)anon.org (anon) writes:
>Adjust your heap size in the linking phase.
>
>In <g3qc68$5a5$1(a)aioe.org>, Dennis Hoppe <dennis.hoppe(a)hoppinet.de> writes:
>>Hi,
>>
>>my machine has 4 GB of RAM and I am wondering, why I can't use
>>at least 2 or 3 GBytes to run an Ada program. It seems, that my
>>Ada Compiler (Gnat 4.4.0) limit the memory to 2 GB per default.
>>Is it possible to allocate more than 2 GB?
>>
>>Here is a simple example of an "evil" vector, that gains
>>more memory in each pass. The program terminates exactly at
>>1024 MB of used Heap memory.
>>
>>
>>with Ada.Containers.Vectors;
>>
>>procedure Heap is
>> package Generic_Vector is new Ada.Containers.Vectors
>> (Element_Type => Integer, Index_Type => Natural);
>>
>> Evil_Vector : Generic_Vector.Vector;
>>begin -- Heap
>> loop
>> Generic_Vector.Append (Evil_Vector, Integer'Last);
>> end loop;
>>end Heap;
>>
>>
>>heap(6374) malloc: *** mmap(size=2147487744) failed (error code=12)
>>*** error: can't allocate region
>>*** set a breakpoint in malloc_error_break to debug
>>
>>raised STORAGE_ERROR : heap exhausted
>>
>>
>>I could not find a suitable Compiler switch or a parameter, that
>>can be set for the operating system (linux). "ulimit -v" is already
>>set to unlimited.
>>
>>"gnatmem" reports, that my water mark with 1024 MB is reached, but
>>the final water mark is, needless to say, higher.
>>
>>
>>Best regards,
>> Dennis Hoppe
>

From: tmoran on 24 Jun 2008 20:11
> but in Ada: Integers are 4 bytes
The Ada 95 Reference Manual 3.5.4(21) says
"In an implementation, the range of Integer shall include the range
-2**15+1 .. +2**15-1."
Has this changed in Ada 2005?
From: anon on 24 Jun 2008 22:49
RM for Ada 95 and Ada 2005 -- 3.5.4 ( 21 ) : says that an Integer must
include the range

-2**15+1 .. +2**15-1 aka -32768 .. +32767

but it is not limited to that range. Check RM 3.5.4 ( 26 ).
The norm for PC's Integer is -2**32+1 .. +2**32-1

To verify what the true range is on your Ada system look at the
Standard package. For GNAT it is build into the compiler so type
"gnat standard >standard.ads"

Then look at file "standard.ads" you will see lines:

package Standard is
pragma Pure(Standard);

type Boolean is (False, True);


type Integer is range -(2 ** 31) .. +(2 ** 31 - 1);

subtype Natural is Integer range 0 .. +(2 ** 31 - 1);
...
end Standard;


Or try this program
--
-- i.adb
--
with Ada.Text_IO ;
use Ada.Text_IO ;
with Ada.Integer_Text_IO ;
use Ada.Integer_Text_IO ;

procedure i is

begin
put ( Integer'Last ) ;
new_line ;
end ;



In <FJSdndpDzI7XEPzVnZ2dnUVZ_rfinZ2d(a)comcast.com>, tmoran(a)acm.org writes:
>> but in Ada: Integers are 4 bytes
>The Ada 95 Reference Manual 3.5.4(21) says
>"In an implementation, the range of Integer shall include the range
>-2**15+1 .. +2**15-1."
> Has this changed in Ada 2005?

From: christoph.grein on 25 Jun 2008 04:04
On 25 Jun., 04:49, a...(a)anon.org (anon) wrote:
> RM for Ada 95 and Ada 2005 -- 3.5.4 ( 21 ) : says that an Integer must
> include the range
>
>   -2**15+1 .. +2**15-1   aka     -32768 .. +32767
>
> but it is not limited to that range. Check RM 3.5.4  ( 26 ).

Paragraph (26) has nothing to do with Integer - it's about nonstandard
integer types, and Integer is a standard integer type.

> The norm for PC's Integer is -2**32+1 .. +2**32-1

You surely mean -(2**31) .. (2**31) - 1

"Norm"? You mean it's generally the case... There is no (DIN, EU, ...)
norm, or is there.
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