https://static.rust-lang.org/dist/rustc-1.38.0-src.tar.gz
https://static.rust-lang.org/dist/2019-08-15/rust-std-1.37.0-x86_64-unknown-linux-musl.tar.gz#no-extract
https://static.rust-lang.org/dist/2019-08-15/rustc-1.37.0-x86_64-unknown-linux-musl.tar.gz#no-extract
https://static.rust-lang.org/dist/2019-08-15/cargo-0.38.0-x86_64-unknown-linux-musl.tar.gz#no-extract
patches/musl-libressl.patch