I am trying to compile the library AGMG.
The make file for the parallel example is looking like this:
# MPIopt = -I/... (where to find mpif.h)
# MUMPSPopt = -I/... (where to find files to be included by
# applications using MUMPS)
# MUMPSlib = -l... (link reference for MUMPS)
# SCALAP = -l... (link reference for SCALAPACK, needed by MUMPS)
# BLASLAPACK= -l... (link reference for LAPACK & BLAS)
# MPIlib = -l... (link reference for MPI)
On my Debian mpif.h is found:
$ ls /usr/lib/openmpi/include/mpi.h
/usr/lib/openmpi/include/mpi.h
So I wrote in the Makefile:
MPIopt = -I/usr/lib/openmpi/include/
MPIlib = -lmpi
But never the less, when I try to compile, I get the following errors:
:~/AGMG_3.0/Example_par$ make
cd ../SRC;make dpar
make[1]: Entering directory `AGMG_3.0/SRC'
make[1]: Nothing to be done for `dpar'.
make[1]: Leaving directory `AGMG_3.0/SRC'
gfortran-4.4 -O4 -o Example_par Example_par.o ../SRC/dagmg_par.o -lmpi
Example_par.o: In function `MAIN__':
Example_par.f90:(.text+0x77): undefined reference to `mpi_init_'
....
....
....
dagmg_par.f90:(.text+0x19fc9): undefined reference to `mpi_comm_rank_'
dagmg_par.f90:(.text+0x19fdd): undefined reference to `mpi_comm_size_'
collect2: ld returned 1 exit status
make: *** [Example_par] Error 1
I'm quite confused by now, I had tries that succeeded, but than I had problems with scaplap and the other requirements. scalap is found:
$ dpkg -L libscalapack-mpi-dev
/.
/usr
/usr/lib
/usr/lib/libscalapack-openmpi.a
mumps is found in /usr/lib/libsmumps.a and the header files are in /usr/include/smumps_c.h
So how do I put all this together?
I know that for a more advanced fortran or C developer this would be trivial ...
Thanks in advance for your help.
EDIT: I'm putting here the full Makefile definitions, in hope it might help others:
MPIopt = -I/usr/lib/openmpi/include -I/usr/lib/openmpi/lib -L/usr/lib/openmpi/lib -pthread
MPIlib = -lmpi_f90 -lmpi_f77 -lmpi
MUMPSPopt = -I/usr/lib/libsmumps.a -I/usr/lib/libdmumps.a
MUMPSlib = -lsmumps -ldmumps
BLASLAPACK=-L/usr/lib -llapack -lblas
BLASLAPACK=-L/usr/lib -llapack -lblas
SCALAP = -L/usr/lib/libscalapack-openmpi.a -lscalapack-openmpi
F90=gfortran-4.6
This builds it. Thanks for the replies!
These are linker errors. It looks like your include files have been picked up successfully, but the linker is not seeing the MPI library. Try changing MPIlib = -lmpi to something that includes the path to libmpi.a, such as MPIlib = -L/usr/lib/openmpi/lib -lmpi
Alternatively, try using the MPI compiler wrappers, as suggested by @haraldkl. These should take care of linking to MPI automatically.