Rust Crates换源

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mkdir -pv ~/.cargo
cat > ~/.cargo/config << "EOF"
[source.crates-io]
replace-with = "ustc"
[source.ustc]
registry = "sparse+https://mirrors.ustc.edu.cn/crates.io-index/"
EOF
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编译Rust时需要获取上一个版本的Rust来进行构建, 可以预先在指定位置下载好二进制Rust安装包以提升速度。
以Rust 1.76.0为例, 下载
1. https://static.rust-lang.org/dist/cargo-1.75.0-x86_64-unknown-linux-gnu.tar.xz
2. https://static.rust-lang.org/dist/rust-std-1.75.0-x86_64-unknown-linux-gnu.tar.xz
2. https://static.rust-lang.org/dist/rustc-1.75.0-x86_64-unknown-linux-gnu.tar.xz
并将它们放置于build/cache/2023-12-28目录中(发行日期见https://github.com/rust-lang/rust/releases)。