/usr/mips64el-linux-gnuabi64/lib32/libgfortran.so.3 is in libn32gfortran3-mips64el-cross 6.3.0-18cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/mips64el-linux-gnuabi64/lib32/libgfortran.so.3.0.0