[MPICH] Linking difficulty

[David Ashton]

Jon,

It appears from the unresolved symbols that you are using the stdcall
function calling convention and therefore you need to link with the
fmpich2s.lib library in MPICH2.

Also, it appears that you are linking with a library that provides dummy
stubs for the MPI functions.  You will need to place fmpich2s.lib before the
IMSL library so you link with the real MPI library.

I'm not familiar with the IMSL library but if it comes pre-compiled for MPI
then you need to make sure you use the same version of MPI that the library
was compiled to use.

-David Ashton

-----Original Message-----
From: owner-mpich-discuss at mcs.anl.gov
[mailto:owner-mpich-discuss at mcs.anl.gov] On Behalf Of Jon Huntley
Sent: Monday, June 20, 2005 9:44 AM
To: mpich-discuss at mcs.anl.gov
Subject: [MPICH] Linking difficulty

I apologize if this is a really stupid question, but I am quite the novice
programmer.

So I have a simulation that I'm compiling with Compaq Visual Fortran 6.6.0
in Windows XP, and I've been asked to see if I can make it run faster with
parallel processing.  So I've installed MPICH2, followed all of the
instructions in the readme, and made a nice little test run of my program in
Windows on a single processor machine where I bounce messages back and forth
between processes.  To me, this is really nifty.

The problem is that this only works in the Debug mode.  If I use the Release
mode (which is about twice as fast for this program without MPI, so this is
a serious concern), I get all manner of linker errors, although compiling
always seems to go through error free.  For example, I get:
LINK : warning LNK4089: all references to "fmpich2.dll" discarded by
/OPT:REF

So I choose /OPT:NOREF and I get the following error upon execution:
FATAL ERROR 1 from MPI_INIT.  A CALL was executed using the IMSL dummy
routine.  Parallel performance needs a functioning MPI library.

Furthermore, if I include calls to the subroutines MPI_SEND and MPI_RECV, I
unavoidably get the error (/OPT:NOREF doesn't get me past this):
Model.obj : error LNK2001: unresolved external symbol _MPI_SEND at 32
Model.obj : error LNK2001: unresolved external symbol _MPI_RECV at 36

I've tried copying all of the libraries I know about into the program
directories, I've tried all of the switches and options I know about (going
through and comparing diligently the options under the Debug and Release
modes), and I can't seem to find anything.  Does anybody have any
suggestions on some things to try, or any ideas on what I'm doing wrong?  

Thanks,
Jon