Configuration of the GFortran compiler to use it with Abaqus

To use GNU Fortran Compiler with Abaqus the compiler and linker options in Abaqus config file must be modified. The following statements added to global (lnx86_64.env) or local (abaqus_v6.env) Abaqus configuration files enables to compile and to link Abaqus user subroutines on Linux using GFortran:

import os

abaHomeInc = os.path.abspath(os.path.join(os.environ.get('ABA_HOME', ''), os.pardir))

fortCmd = "gfortran"

compile_fortran = [fortCmd,
                   '-c', '-cpp', '-fPIC','-extend-source',
                   '-DABQ_LNX86_64', '-DABQ_FORTRAN',
                   '-fautomatic',
                   '-mno-fma', 
                   '-fprotect-parens',
                   '-fstack-protector-strong',
                   '-msse3',
                   '-mavx', '-mavx2',
                   '-ffixed-line-length-none',
                   '-I%I', '-I'+abaHomeInc, '%P']

link_sl = [fortCmd,
           '-fPIC', '-shared','-Wl,--add-needed', 
           '%E', '-Wl,-soname,%U', '-o', '%U', '%F', '%A', '%L', '%B',
           '-Wl,-Bdynamic']

link_exe = [fortCmd,
            '-fPIC',
            '-Wl,-Bdynamic', '-Wl,--add-needed', '-o', '%J', '%F', '%M', '%L', '%B', '%O']

del fortCmd
del abaHomeInc

To debug a subroutine, it must be compiled with -g option to produce debugging information. In the case of GDB you can use -ggdb3 to produce debugging information for use by GDB specifically. It can be done by modifying Abaqus environment variable compile_fortran in Abaqus environment file:

compile_fortran=compile_fortran + ['-ggdb3', '-std=legacy', '-fcheck=all', '-fbacktrace', '-static']

More about debugging Abaqus usersubroutines on Linux can be found here.

The easiest way to set it up is to put the provided here abaqus_v6.env file to your home directory or directory where you run Abaqus with subroutines. If you have abaqus_v6.env already, copy the statements which define and delete variables to your abaqus_v6.env file.

To check if it works correctly run the command:

$ abaqus verify user_std user_exp make

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Abaqus Product Verification

Mon 17 Jan 2022 10:11:25 PM CET

------------------------------------------------------------

Verify test : Abaqus/Standard with user subroutines verification

     result : PASS

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Verify test : Abaqus/Explicit with user subroutines verification

  - 'Abaqus/Explicit single precision user subroutine' completed, validation Succeeded

  - 'Abaqus/Explicit double precision user subroutine' completed, validation Succeeded

     result : PASS

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Verify test : Abaqus make utility verification

  - 'Abaqus make C++ verification' completed, validation Succeeded

  - 'Abaqus make C++ PostProcess Application' completed, validation Succeeded

  - 'Abaqus make Fortran verification' completed, validation Succeeded

  - 'Abaqus make Fortran PostProcess Application' completed, validation Succeeded

  - 'Abaqus make object file verification' completed, validation Succeeded

  - 'Abaqus make object file PostProcess Application' completed, validation Succeeded

     result : PASS

------------------------------------------------------------

Verification procedure complete

Mon 17 Jan 2022 10:11:54 PM CET

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Happy coding!

References:

1. The GNU Fortran Compiler
2. A GNU Manual
3. Using GNU Fortran