This is is pre-built compiler tool chain for various platforms cross-compiling for various ARM targets.

Newer distributions may have the tools already

sudo apt-get install gcc-arm-none-eabi gdb-multiarch

Otherwise download the latest from here.

mkdir -p /opt
cd /opt
wget https://github.com/vanbwodonk/gcc-arm-embedded-build-armhf/releases/download/9-2019-q4-major/gcc-arm-none-eabi-9-2020-q1-update-armv7l-linux.tar.bz2
tar jxvf gcc-arm-none-eabi-9-2020-q1-update-armv7l-linux.tar.bz2

gcc-arm for Intel and AARCH64

gcc-arm for RPi