There is a strange lack of guides and tools online for compiling Gameboy Advance homebrew programs on Linux. I didn't want to use devkitpro - their installation method of requiring you to use a forked version of pacman is extemely strange and I didn't want to install all of that on my system just to complile some programs.
The only other guides I found for Linux were this one and this one which both involve compiling custom versions of GCC and assosicated libraries. This lead me down a road of pain, after spending multiple hours fixing compiler errors only to create new errors I gave up. I thought that their had to be a simpler way, and there is!
Debian already has a version of GCC that can compile ARM programs in the repos, no manual compiling necessary! The package is called arm-none-eabi-gcc
.