Newsgroups: comp.parallel.mpi
From: Michael Schulz <micha@nats.informatik.uni-hamburg.de>
Subject: Re: lam mpi error with linux
Organization: NatS Uni-Hamburg
Date: Tue, 28 Jul 1998 16:49:01 +0200
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Message-ID: <35BDE4DD.261C72FD@nats.informatik.uni-hamburg.de>

Cary B. O'Brien wrote:
> 
> It is possible that you have a hardware problem.  

Hi everybody,

segfaults at different places in code mustnt be a
hardwareerror. Similar
errors occure when dynamicaly allocated memory is freed
twice. That's 
what i call a negative memory whole. Under linux the
memory-allocation
scheme seems to get confused by things like that. I came
accross this
when porting stuff from Solaris to Linux. 

When your part of the program misbehaves the mpi part could
fail 
somewhere while allocating a new chunk of memory and things
suddenly
get confused arround there.

Try to uncomment your free()s. Better use macros like
#define myFree(x) free(x).

	Regards,
	Micha.


-- Michael Schulz
-- NatS (Natural Language Systems), Uni Hamburg