/usr/share/man/man1/gsdh_gnustep.1.gz is in gnustep-make 2.6.6-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man1/dh_gnustep.1.gz
/usr/share/man/man1/dh_gnustep.1.gz