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Message: 6
Date: Fri, 25 Apr 2008 14:10:57 -0600
From: Brian Barrett <brbarret@open-mpi.org>
Subject: Re: [OMPI users] Memory question and possible bug in 64bit
addressing under Leopard!
To: Open MPI Users <users@open-mpi.org>
Message-ID: <C9986452-B565-454D-8F79-E7C5E0571A19@open-mpi.org>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes

On Apr 25, 2008, at 2:06 PM, Gregory John Orris wrote:

produces a core dump on a machine with 12Gb of RAM.

and the error message

mpiexec noticed that job rank 0 with PID 75545 on node mymachine.com

exited on signal 4 (Illegal instruction).

However, substituting in

float *X = new float[n];

for

float X[n];

Succeeds!

You're running off the end of the stack, because of the large amount  
of data you're trying to put there.  OS X by default has a tiny stack  
size, so codes that run on Linux (which defaults to a much larger  
stack size) sometimes show this problem.  Your best bets are either to  
increase the max stack size or (more portably) just allocate  
everything on the heap with malloc/new.

Hope this helps,

Brian

-- 
  Brian Barrett
  Open MPI developer
  http://www.open-mpi.org/