$ ls -l /opt/toolchains/
total 16
drwxr-xr-x 6 root  root 4096 Feb  4 03:44 gcc-arm-none-eabi-6-2017-q1-update
drwxr-xr-x 8 11827 9000 4096 Feb 16  2017 gcc-linaro-6.3.1-2017.02-x86_64_aarch64-linux-gnu
drwxr-xr-x 7  1001 1001 4096 Nov 19  2013 gcc-linaro-aarch64-none-elf-4.8-2013.11_linux
drwxr-xr-x 7  1001 1001 4096 Apr 17  2014 gcc-linaro-arm-none-eabi-4.8-2014.04_linux