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Subject: Re: [OMPI users] Open MPI error to define MPI_Datatype in header file
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2011-10-10 09:58:20

You'll need to be a bit more specific. What describe should work fine.

extern MPI_Datatype mydtype;
#inlclude "foo.h"
MPI_Datatype mydtype;
#include "foo.h"
void bogus(void) {
  MPI_Datatype foo = mydtype;

On Oct 9, 2011, at 4:10 PM, Jack Bryan wrote:

> Hi,
> I need to define a (Open MPI) MPI_Datatype in a header file so that all other files that include it can find it.
> I also try to use extern to do decleration in .h file and then define them in .cpp file.
> But, I always get error:
> undefined reference
> It is not allowed in Open MPI ?
> Why ?
> Any help is really appreciated.
> Thanks
> _______________________________________________
> users mailing list
> users_at_[hidden]

Jeff Squyres
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