/usr/sparc64-linux-gnu/lib/libgnatprj.so is in libgnatprj6-dev-sparc64-cross 6.3.0-18cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/sparc64-linux-gnu/lib/libgnatprj.so.6
/usr/sparc64-linux-gnu/lib/libgnatprj.so.6