I am doing the same but with LLVM. For starters, I filtered issues with the "good first issue" label and found something to work on [1]. It took 2 months in review and about a month to research and write the code. Finally got merged yesterday. I am writing about it so that when someone else bumps into the same problem, they hopefully take 1 hour instead of 1 month. Compilers, like the kernel, are a lot of fun!

[1] https://github.com/llvm/llvm-project/pull/154914