/usr/lib/x86_64-linux-gnu/fis-gtm/V6.3-000A_x86_64/utf8/_GC.m is in fis-gtm-6.3-000a 6.3-000A-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/fis-gtm/V6.3-000A_x86_64/utf8/../_GC.m