topic Re: Fortran shared lib .so shows undefined symbol error in Intel® Fortran Compiler

Fortran shared lib .so shows undefined symbol error

csH2 — Thu, 14 Oct 2021 15:30:15 GMT

Hi everyone I need help about a compilation issue.

I'm compiling a Fortran code to obtain shared library .so. In the code it uses a module. The compiling has no problem while it reports undefined symbol error when opening the .so library.

Code mesh_map.F are as follows:

#include "cfx5ext.h" dllexport(mesh_map) SUBROUTINE mesh_map (CZ, DZ, IZ, LZ, RZ) USE EXTRA_FLUID2 USE ISO_C_BINDING USE IFPORT IMPLICIT NONE CHARACTER*(1) CZ(*) DOUBLE PRECISION DZ(*) INTEGER IZ(*) LOGICAL LZ(*) REAL RZ(*) MAP_STATUS = 1 END

extra_fluid2.f90:

Module EXTRA_FLUID2 INTEGER :: map_status = 0 end module EXTRA_FLUID2

Compiling command:

ifort -c extra_fluid2.f90 /home/xxx/intel/oneapi/compiler/2021.4.0/linux/bin/intel64/ifort -fpic -assume 2underscore -check uninit -warn declarations -diag-error 6717 -ftz -O2 -fp-speculation=safe -fp-model=precise -fp-model=source -fimf-arch-consistency=true -qno-opt-dynamic-align -fpe0 -fomit-frame-pointer -real-size 32 -integer-size 32 -I/usr/ansys_inc/v192/CFX/include -o linux-amd64/ifort/mesh_map.o -c mesh_map.F -lrt/xxx/intel/oneapi/compiler/2021.4.0/linux/bin/intel64/ifort -shared -o ./linux-amd64/ifort/libmesh_map.so linux-amd64/ifort/mesh_map.o extra_fluid2.o

When I check the .so library using:

ldd -r libmesh_map.so

The result shows as:

undefined symbol: extra_fluid2_mp_map_status__ (./libmesh_map.so)

How can I fix this? Thanks in advance.

I've tried compilation in Windows and no problem was found for the dll file. While in Linux it reports above error.

Re: Fortran shared lib .so shows undefined symbol error

Steve_Lionel — Thu, 14 Oct 2021 16:53:23 GMT

When you compiled mesh_map.F, you specified -assume 2underscore, but didn't specify that when compiling extra_fluid2.f90. This causes the global symbols to be inconsistent. Take that off.

I'm also puzzled by the "dllexport(meshmap)" in mesh_map.F. I have to assume that's a macro defined in the #include.

Re: Fortran shared lib .so shows undefined symbol error

Barbara_P_Intel — Thu, 14 Oct 2021 20:41:50 GMT

dllexport is not required for Linux. Here's more info.

Re: Fortran shared lib .so shows undefined symbol error

csH2 — Sat, 16 Oct 2021 15:09:10 GMT

Thank you Steve! Yes, I think dllexport should be removed.

Re: Fortran shared lib .so shows undefined symbol error

csH2 — Sat, 16 Oct 2021 15:10:06 GMT

Yes. Thank you for your reply!