/usr/bin/arm-linux-gnueabi-gnatgcc is in gnat-8-arm-linux-gnueabi 8-20180414-1ubuntu2cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/bin/arm-linux-gnueabi-gcc-8
/usr/bin/arm-linux-gnueabi-gcc-8