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Subject: Re: [OMPI devel] malloc(0) warnings
From: George Bosilca (bosilca_at_[hidden])
Date: 2010-05-06 15:36:08


This is an artifact of using the gatherv (or the scatterv) on an inter-communicator without any useful data (i.e. either count of zero or empty datatypes). Looks more like a synchronization than a real operation.

  george.

On May 5, 2010, at 20:17 , Lisandro Dalcin wrote:

> After building 1.4.2 with debug flags to configure, I get this (I've
> got these warnings in previous releases, too):
>
> malloc debug: Request for 0 bytes (coll_inter_gatherv.c, 94)
> malloc debug: Request for 0 bytes (coll_inter_gatherv.c, 94)
> malloc debug: Request for 0 bytes (coll_inter_gatherv.c, 94)
> malloc debug: Request for 0 bytes (coll_inter_gatherv.c, 94)
>
> malloc debug: Request for 0 bytes (coll_inter_scatterv.c, 82)
> malloc debug: Request for 0 bytes (coll_inter_scatterv.c, 82)
> malloc debug: Request for 0 bytes (coll_inter_scatterv.c, 82)
> malloc debug: Request for 0 bytes (coll_inter_scatterv.c, 82)
>
>
> --
> Lisandro Dalcin
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