Re: Larger matrices

["Alex R. Mosteo" <devnull@mailinator.com>]

amado.alves@gmail.com wrote:

> I manage to process 1000 x 1000 matrices with the respective Ada 2005
> standard library with GNAT GPL 2008. Processing includes
> multiplication by a vector.
> 
> Now I want larger matrices, say 5000 x 5000. The objects seem to be
> allocated ok (dynamically), but mutiplication gives a "segmentation
> fault."
> 
> Any tips on how to overcome this?

I will give you all the tips I remember on how to get larger stacks (in linux),
but I'm going from memory so you'll have to double-check:

ulimit -s unlimited at the shell level.

Wrap your program, if not already, in a task to be able to use pragma
Storage_Size for this task. I see in other posts that there are switches in
order to set the stack size of the environment task; make your choice.

The linker settings are the fuzziest part. This old thread can put you in the
good track:

http://groups.google.com/group/comp.lang.ada/browse_thread/thread/73c865853bdc4937

In particular the first reply mentions arguments to the linker that ring a bell
to me, although I'm sure to have seen at least an alternate suggestion for a
set of linker options dealing with the stack.