Install lib32gfortran5-dbg by entering the following commands in the terminal:
sudo apt update sudo apt install lib32gfortran5-dbg
Description:
Runtime library for GNU Fortran applications (32 bit debug symbols)
Library needed for GNU Fortran applications linked against the shared library.
Homepage: http://gcc.gnu.org/
Version: 8-20180414-1ubuntu2
Section: universe/debug