/usr/bin/arm-linux-gnueabihf-gcc-ar is in gcc-arm-linux-gnueabihf 4:7.3.0-3ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/bin/arm-linux-gnueabihf-gcc-ar-7
/usr/bin/arm-linux-gnueabihf-gcc-ar-7