# Libmpifort.so.12: undefined symbol: MPI\_UNWEIGHTED **URL:** \ **Category:** General Discussion\ **Created:** [April 8, 2021, 5:10pm UTC](https://community.freefem.org/t/libmpifort-so-12-undefined-symbol-mpi-unweighted/900 "2021-04-08T17:10:34Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![jeyc](https://avatars.discourse-cdn.com/v4/letter/j/b487fb/32.png) [@jeyc](https://community.freefem.org/u/jeyc)\ **Post date:** [April 8, 2021, 5:10pm UTC](https://community.freefem.org/t/libmpifort-so-12-undefined-symbol-mpi-unweighted/900/1 "2021-04-08T17:10:34Z")
Hello, I have installed FreeFem++ 4.8. When I run this command: /usr/local/share/freefem++/4.8/bin/ff-mpirun -np 2 mesh.edp I get this error: /usr/local/share/freefem++/4.8/bin/FreeFem+±mpi: symbol lookup error: /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libmpifort.so.12: undefined symbol: MPI\_UNWEIGHTED any sugestion please? Thank you. ---
**Author:** ![prj](https://avatars.discourse-cdn.com/v4/letter/p/ecae2f/32.png) [@prj](https://community.freefem.org/u/prj)\ **Post date:** [April 8, 2021, 6:55pm UTC](https://community.freefem.org/t/libmpifort-so-12-undefined-symbol-mpi-unweighted/900/2 "2021-04-08T18:55:46Z")
Could you please copy/paste the result of `ldd /usr/local/share/freefem++/4.8/bin/FreeFem++-mpi`? ---
**Author:** ![jeyc](https://avatars.discourse-cdn.com/v4/letter/j/b487fb/32.png) [@jeyc](https://community.freefem.org/u/jeyc)\ **Post date:** [April 9, 2021, 6:01am UTC](https://community.freefem.org/t/libmpifort-so-12-undefined-symbol-mpi-unweighted/900/3 "2021-04-09T06:01:38Z")
Hello, ldd /usr/local/share/freefem++/4.8/bin/FreeFem+±mpi linux-vdso.so.1 =\> (0x00007ffe9d536000) libumfpack.so.5 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libumfpack.so.5 (0x00007f722a71e000) libklu.so.1 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libklu.so.1 (0x00007f722a4c6000) libcholmod.so.3 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libcholmod.so.3 (0x00007f722a16e000) libbtf.so.1 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libbtf.so.1 (0x00007f7229f66000) libccolamd.so.2 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libccolamd.so.2 (0x00007f7229d56000) libcolamd.so.2 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libcolamd.so.2 (0x00007f7229b46000) libcamd.so.2 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libcamd.so.2 (0x00007f7229936000) libamd.so.2 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libamd.so.2 (0x00007f7229726000) libsuitesparseconfig.so.5 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libsuitesparseconfig.so.5 (0x00007f722951e000) libmetis.so =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libmetis.so (0x00007f722929e000) libarpack.so.2 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libarpack.so.2 (0x00007f7228fae000) libmpicxx.so.12 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libmpicxx.so.12 (0x00007f7228d86000) libmpi.so.12 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libmpi.so.12 (0x00007f7228846000) libdl.so.2 =\> /lib64/libdl.so.2 (0x00007f722863e000) librt.so.1 =\> /lib64/librt.so.1 (0x00007f7228436000) libgfortran.so.3 =\> /lib64/libgfortran.so.3 (0x00007f722810e000) libm.so.6 =\> /lib64/libm.so.6 (0x00007f7227e06000) libquadmath.so.0 =\> /lib64/libquadmath.so.0 (0x00007f7227bc6000) libz.so.1 =\> /lib64/libz.so.1 (0x00007f72279ae000) libpthread.so.0 =\> /lib64/libpthread.so.0 (0x00007f722778e000) libhdf5.so.8 =\> /lib64/libhdf5.so.8 (0x00007f7227196000) libhdf5\_hl.so.8 =\> /lib64/libhdf5\_hl.so.8 (0x00007f7226f5e000) libstdc++.so.6 =\> /lib64/libstdc++.so.6 (0x00007f7226c56000) libgcc\_s.so.1 =\> /lib64/libgcc\_s.so.1 (0x00007f7226a3e000) libc.so.6 =\> /lib64/libc.so.6 (0x00007f722666e000) libmpifort.so.12 =\> /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libmpifort.so.12 (0x00007f7226436000) libgomp.so.1 =\> /lib64/libgomp.so.1 (0x00007f722620e000) /lib64/ld-linux-x86-64.so.2 (0x00007f722aa46000) libXNVCtrl.so.0 =\> /lib64/libXNVCtrl.so.0 (0x00007f7226006000) libXext.so.6 =\> /lib64/libXext.so.6 (0x00007f7225dee000) libX11.so.6 =\> /lib64/libX11.so.6 (0x00007f7225aae000) libsz.so.2 =\> /lib64/libsz.so.2 (0x00007f72258a6000) libxcb.so.1 =\> /lib64/libxcb.so.1 (0x00007f722567e000) libaec.so.0 =\> /lib64/libaec.so.0 (0x00007f7225476000) libXau.so.6 =\> /lib64/libXau.so.6 (0x00007f722526e000) Thank you. ---
**Author:** ![prj](https://avatars.discourse-cdn.com/v4/letter/p/ecae2f/32.png) [@prj](https://community.freefem.org/u/prj)\ **Post date:** [April 9, 2021, 6:21am UTC](https://community.freefem.org/t/libmpifort-so-12-undefined-symbol-mpi-unweighted/900/4 "2021-04-09T06:21:20Z")
How about `nm /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libmpi.so.12|grep MPI_UNWEIG`? ---
**Author:** ![jeyc](https://avatars.discourse-cdn.com/v4/letter/j/b487fb/32.png) [@jeyc](https://community.freefem.org/u/jeyc)\ **Post date:** [April 9, 2021, 6:42am UTC](https://community.freefem.org/t/libmpifort-so-12-undefined-symbol-mpi-unweighted/900/5 "2021-04-09T06:42:56Z")
nm /usr/local/share/freefem++/4.8/ff-petsc/r/lib/libmpi.so.12|grep MPI\_UNWEIG 0000000000537928 b MPIR\_C\_MPI\_UNWEIGHTED 000000000051e970 B MPIR\_F\_MPI\_UNWEIGHTED 00000000004f4848 D MPI\_UNWEIGHTED ---
**Author:** ![prj](https://avatars.discourse-cdn.com/v4/letter/p/ecae2f/32.png) [@prj](https://community.freefem.org/u/prj)\ **Post date:** [April 9, 2021, 7:06am UTC](https://community.freefem.org/t/libmpifort-so-12-undefined-symbol-mpi-unweighted/900/6 "2021-04-09T07:06:06Z")
OK, maybe that’s because you have some HDF5 libraries that may mess things up. Could you please reconfigure with the added parameter `--without-hdf5`? ---
**Author:** ![jeyc](https://avatars.discourse-cdn.com/v4/letter/j/b487fb/32.png) [@jeyc](https://community.freefem.org/u/jeyc)\ **Post date:** [April 12, 2021, 7:53am UTC](https://community.freefem.org/t/libmpifort-so-12-undefined-symbol-mpi-unweighted/900/7 "2021-04-12T07:53:13Z")
Hello, it seems the problem was one of permissions. I have installed as user (not root) freefem ++ v4.8 in the required user’s / home directory and it works correctly. Thank you.