[INFO] cloning repository https://github.com/liulinboyi/rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/liulinboyi/rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fliulinboyi%2Frust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fliulinboyi%2Frust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] af4ca473c5b4852c7e0ef41a03108ef62395539b
[INFO] testing liulinboyi/rust against beta-2022-04-10 for beta-1.61-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fliulinboyi%2Frust" "/workspace/builds/worker-115/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-115/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/liulinboyi/rust on toolchain beta-2022-04-10
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-04-10" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/liulinboyi/rust
[INFO] finished tweaking git repo https://github.com/liulinboyi/rust
[INFO] tweaked toml for git repo https://github.com/liulinboyi/rust written to /workspace/builds/worker-115/source/Cargo.toml
[INFO] crate git repo https://github.com/liulinboyi/rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-04-10" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4acb6c443eac3318eb239e30f525856e81864d4f4f7b4ca7a30aeed00b132cab
[INFO] running `Command { std: "docker" "start" "-a" "4acb6c443eac3318eb239e30f525856e81864d4f4f7b4ca7a30aeed00b132cab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4acb6c443eac3318eb239e30f525856e81864d4f4f7b4ca7a30aeed00b132cab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4acb6c443eac3318eb239e30f525856e81864d4f4f7b4ca7a30aeed00b132cab", kill_on_drop: false }`
[INFO] [stdout] 4acb6c443eac3318eb239e30f525856e81864d4f4f7b4ca7a30aeed00b132cab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8d0504ba1bba8f76b264ce0b2946632275a7f592ad0d15fd03903d936c32d09a
[INFO] running `Command { std: "docker" "start" "-a" "8d0504ba1bba8f76b264ce0b2946632275a7f592ad0d15fd03903d936c32d09a", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.106
[INFO] [stderr]    Compiling ppv-lite86 v0.2.15
[INFO] [stderr]    Compiling getrandom v0.2.3
[INFO] [stderr]    Compiling rand_core v0.6.3
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling rand v0.8.4
[INFO] [stderr]    Compiling hello v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `core::panic`
[INFO] [stdout]  --> src/error/mod.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use core::panic;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread::sleep`
[INFO] [stdout]  --> src/tiem/mod.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::thread::sleep;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `files`
[INFO] [stdout]    --> src/error/mod.rs:134:9
[INFO] [stdout]     |
[INFO] [stdout] 134 |     let files = file();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_files`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `data`
[INFO] [stdout]    --> src/error/mod.rs:147:12
[INFO] [stdout]     |
[INFO] [stdout] 147 |         Ok(data) => {
[INFO] [stdout]     |            ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `data`
[INFO] [stdout]    --> src/error/mod.rs:164:12
[INFO] [stdout]     |
[INFO] [stdout] 164 |         Ok(data) => {}
[INFO] [stdout]     |            ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/error/mod.rs:36:24
[INFO] [stdout]    |
[INFO] [stdout] 36 |     fn divide_by_three(x: u32) -> u32 {
[INFO] [stdout]    |                        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `content`
[INFO] [stdout]    --> src/error/mod.rs:115:13
[INFO] [stdout]     |
[INFO] [stdout] 115 |         let content: &str = std::str::from_utf8(&data)?;
[INFO] [stdout]     |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_content`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `err`
[INFO] [stdout]   --> src/guess_number.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 |             Err(err) => continue,
[INFO] [stdout]    |                 ^^^ help: if this is intentional, prefix it with an underscore: `_err`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `unit`
[INFO] [stdout]   --> src/my_struct.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let unit = Unit;
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_unit`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/my_type_conversion.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let a = [0u8, 0u8, 0u8, 0u8];
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `box_arr`
[INFO] [stdout]    --> src/pointer_box/mod.rs:105:9
[INFO] [stdout]     |
[INFO] [stdout] 105 |     let box_arr = Box::new(arr); // arr这个数据已经放到堆上面了，这个放到堆上面的动作一定会发生内存拷贝的
[INFO] [stdout]     |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_box_arr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value2`
[INFO] [stdout]    --> src/traits/mod.rs:100:13
[INFO] [stdout]     |
[INFO] [stdout] 100 |         let value2 = 2;
[INFO] [stdout]     |             ^^^^^^ help: if this is intentional, prefix it with an underscore: `_value2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s_ref1`
[INFO] [stdout]    --> src/traits/mod.rs:193:9
[INFO] [stdout]     |
[INFO] [stdout] 193 |     let s_ref1 = &jack;
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_s_ref1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s_ref2`
[INFO] [stdout]    --> src/traits/mod.rs:194:9
[INFO] [stdout]     |
[INFO] [stdout] 194 |     let s_ref2 = &jack;
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_s_ref2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/pointer_box/mod.rs:147:9
[INFO] [stdout]     |
[INFO] [stdout] 147 |     let mut n1 = Node {
[INFO] [stdout]     |         ----^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_guess_number`
[INFO] [stdout]    --> src/main.rs:136:4
[INFO] [stdout]     |
[INFO] [stdout] 136 | fn test_guess_number() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_use_key_words`
[INFO] [stdout]    --> src/main.rs:144:4
[INFO] [stdout]     |
[INFO] [stdout] 144 | fn test_use_key_words() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `divide_by_three`
[INFO] [stdout]   --> src/error/mod.rs:36:8
[INFO] [stdout]    |
[INFO] [stdout] 36 |     fn divide_by_three(x: u32) -> u32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `B`
[INFO] [stdout]    --> src/expressions.rs:123:9
[INFO] [stdout]     |
[INFO] [stdout] 123 |         B,
[INFO] [stdout]     |         ^
[INFO] [stdout]     |
[INFO] [stdout] note: `Alphabet` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    --> src/expressions.rs:120:14
[INFO] [stdout]     |
[INFO] [stdout] 120 |     #[derive(Debug)]
[INFO] [stdout]     |              ^^^^^
[INFO] [stdout]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `B`
[INFO] [stdout]    --> src/expressions.rs:151:9
[INFO] [stdout]     |
[INFO] [stdout] 151 |         B,
[INFO] [stdout]     |         ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `no_return`
[INFO] [stdout]    --> src/function.rs:117:9
[INFO] [stdout]     |
[INFO] [stdout] 117 |      fn no_return() {
[INFO] [stdout]     |         ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `x`
[INFO] [stdout]   --> src/generics/mod.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |         x: T,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:35:14
[INFO] [stdout]    |
[INFO] [stdout] 35 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> src/generics/mod.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |         y: T,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:35:14
[INFO] [stdout]    |
[INFO] [stdout] 35 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `z`
[INFO] [stdout]   --> src/generics/mod.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |         z: U,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:35:14
[INFO] [stdout]    |
[INFO] [stdout] 35 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `x`
[INFO] [stdout]   --> src/generics/mod.rs:62:9
[INFO] [stdout]    |
[INFO] [stdout] 62 |         x: Point<T>,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `Line` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:60:14
[INFO] [stdout]    |
[INFO] [stdout] 60 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> src/generics/mod.rs:63:9
[INFO] [stdout]    |
[INFO] [stdout] 63 |         y: Point<T>,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `Line` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:60:14
[INFO] [stdout]    |
[INFO] [stdout] 60 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `name`
[INFO] [stdout]   --> src/lifecycle/mod.rs:33:9
[INFO] [stdout]    |
[INFO] [stdout] 33 |         name: &'a str, // 这是一个引用，引用了一个字符串，字符串本身有自己的生命周期
[INFO] [stdout]    |         ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `PersonM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/lifecycle/mod.rs:31:14
[INFO] [stdout]    |
[INFO] [stdout] 31 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Fruit`
[INFO] [stdout]  --> src/my_enum.rs:8:10
[INFO] [stdout]   |
[INFO] [stdout] 8 |     enum Fruit {
[INFO] [stdout]   |          ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Color`
[INFO] [stdout]   --> src/my_enum.rs:14:10
[INFO] [stdout]    |
[INFO] [stdout] 14 |     enum Color {
[INFO] [stdout]    |          ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `IPv6`
[INFO] [stdout]   --> src/my_enum.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 | /         IPv6(
[INFO] [stdout] 24 | |             u8,
[INFO] [stdout] 25 | |             u8,
[INFO] [stdout] 26 | |             u8,
[INFO] [stdout] ...  |
[INFO] [stdout] 39 | |             u8,
[INFO] [stdout] 40 | |         ),
[INFO] [stdout]    | |_________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `content`
[INFO] [stdout]   --> src/pointer_box/mod.rs:58:9
[INFO] [stdout]    |
[INFO] [stdout] 58 |         content: String,
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `Link` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/pointer_box/mod.rs:55:14
[INFO] [stdout]    |
[INFO] [stdout] 55 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `tag`
[INFO] [stdout]    --> src/pointer_box/mod.rs:144:9
[INFO] [stdout]     |
[INFO] [stdout] 144 |         tag: String,
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: `Node` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    --> src/pointer_box/mod.rs:141:14
[INFO] [stdout]     |
[INFO] [stdout] 141 |     #[derive(Debug)]
[INFO] [stdout]     |              ^^^^^
[INFO] [stdout]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `name`
[INFO] [stdout]  --> src/str_type/mod.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     name: String,
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] note: `Student` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]  --> src/str_type/mod.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 | #[derive(Debug)]
[INFO] [stdout]   |          ^^^^^
[INFO] [stdout]   = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `show`
[INFO] [stdout]   --> src/traits/mod.rs:19:4
[INFO] [stdout]    |
[INFO] [stdout] 19 | fn show<T: std::fmt::Display>(a: T) {
[INFO] [stdout]    |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `age`
[INFO] [stdout]    --> src/traits/mod.rs:170:9
[INFO] [stdout]     |
[INFO] [stdout] 170 |         age: U,
[INFO] [stdout]     |         ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: `Person` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    --> src/traits/mod.rs:167:14
[INFO] [stdout]     |
[INFO] [stdout] 167 |     #[derive(Debug)]
[INFO] [stdout]     |              ^^^^^
[INFO] [stdout]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:169:5
[INFO] [stdout]     |
[INFO] [stdout] 169 |     pointer_box::pointer_box();
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:181:5
[INFO] [stdout]     |
[INFO] [stdout] 181 |     str_type::str_type();
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/function.rs:62:5
[INFO] [stdout]    |
[INFO] [stdout] 62 | /     thread::spawn(move || {
[INFO] [stdout] 63 | |         println!("{}", hello_message);
[INFO] [stdout] 64 | |     })
[INFO] [stdout] 65 | |     .join(); // join 除非子线程退出，不然主线程会一直去等待
[INFO] [stdout]    | |____________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 38 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 33.29s
[INFO] running `Command { std: "docker" "inspect" "8d0504ba1bba8f76b264ce0b2946632275a7f592ad0d15fd03903d936c32d09a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8d0504ba1bba8f76b264ce0b2946632275a7f592ad0d15fd03903d936c32d09a", kill_on_drop: false }`
[INFO] [stdout] 8d0504ba1bba8f76b264ce0b2946632275a7f592ad0d15fd03903d936c32d09a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 48f9b893f63affd0058693b3324fbddd45a78d7981cf61dd8fc0c37367cdd322
[INFO] running `Command { std: "docker" "start" "-a" "48f9b893f63affd0058693b3324fbddd45a78d7981cf61dd8fc0c37367cdd322", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling hello v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `core::panic`
[INFO] [stdout]  --> src/error/mod.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use core::panic;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread::sleep`
[INFO] [stdout]  --> src/tiem/mod.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::thread::sleep;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `files`
[INFO] [stdout]    --> src/error/mod.rs:134:9
[INFO] [stdout]     |
[INFO] [stdout] 134 |     let files = file();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_files`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `data`
[INFO] [stdout]    --> src/error/mod.rs:147:12
[INFO] [stdout]     |
[INFO] [stdout] 147 |         Ok(data) => {
[INFO] [stdout]     |            ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `data`
[INFO] [stdout]    --> src/error/mod.rs:164:12
[INFO] [stdout]     |
[INFO] [stdout] 164 |         Ok(data) => {}
[INFO] [stdout]     |            ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/error/mod.rs:36:24
[INFO] [stdout]    |
[INFO] [stdout] 36 |     fn divide_by_three(x: u32) -> u32 {
[INFO] [stdout]    |                        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `content`
[INFO] [stdout]    --> src/error/mod.rs:115:13
[INFO] [stdout]     |
[INFO] [stdout] 115 |         let content: &str = std::str::from_utf8(&data)?;
[INFO] [stdout]     |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_content`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `err`
[INFO] [stdout]   --> src/guess_number.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 |             Err(err) => continue,
[INFO] [stdout]    |                 ^^^ help: if this is intentional, prefix it with an underscore: `_err`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `unit`
[INFO] [stdout]   --> src/my_struct.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let unit = Unit;
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_unit`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/my_type_conversion.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let a = [0u8, 0u8, 0u8, 0u8];
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `box_arr`
[INFO] [stdout]    --> src/pointer_box/mod.rs:105:9
[INFO] [stdout]     |
[INFO] [stdout] 105 |     let box_arr = Box::new(arr); // arr这个数据已经放到堆上面了，这个放到堆上面的动作一定会发生内存拷贝的
[INFO] [stdout]     |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_box_arr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value2`
[INFO] [stdout]    --> src/traits/mod.rs:100:13
[INFO] [stdout]     |
[INFO] [stdout] 100 |         let value2 = 2;
[INFO] [stdout]     |             ^^^^^^ help: if this is intentional, prefix it with an underscore: `_value2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s_ref1`
[INFO] [stdout]    --> src/traits/mod.rs:193:9
[INFO] [stdout]     |
[INFO] [stdout] 193 |     let s_ref1 = &jack;
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_s_ref1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s_ref2`
[INFO] [stdout]    --> src/traits/mod.rs:194:9
[INFO] [stdout]     |
[INFO] [stdout] 194 |     let s_ref2 = &jack;
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_s_ref2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/pointer_box/mod.rs:147:9
[INFO] [stdout]     |
[INFO] [stdout] 147 |     let mut n1 = Node {
[INFO] [stdout]     |         ----^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_guess_number`
[INFO] [stdout]    --> src/main.rs:136:4
[INFO] [stdout]     |
[INFO] [stdout] 136 | fn test_guess_number() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_use_key_words`
[INFO] [stdout]    --> src/main.rs:144:4
[INFO] [stdout]     |
[INFO] [stdout] 144 | fn test_use_key_words() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `divide_by_three`
[INFO] [stdout]   --> src/error/mod.rs:36:8
[INFO] [stdout]    |
[INFO] [stdout] 36 |     fn divide_by_three(x: u32) -> u32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `B`
[INFO] [stdout]    --> src/expressions.rs:123:9
[INFO] [stdout]     |
[INFO] [stdout] 123 |         B,
[INFO] [stdout]     |         ^
[INFO] [stdout]     |
[INFO] [stdout] note: `Alphabet` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    --> src/expressions.rs:120:14
[INFO] [stdout]     |
[INFO] [stdout] 120 |     #[derive(Debug)]
[INFO] [stdout]     |              ^^^^^
[INFO] [stdout]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `B`
[INFO] [stdout]    --> src/expressions.rs:151:9
[INFO] [stdout]     |
[INFO] [stdout] 151 |         B,
[INFO] [stdout]     |         ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `no_return`
[INFO] [stdout]    --> src/function.rs:117:9
[INFO] [stdout]     |
[INFO] [stdout] 117 |      fn no_return() {
[INFO] [stdout]     |         ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `x`
[INFO] [stdout]   --> src/generics/mod.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |         x: T,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:35:14
[INFO] [stdout]    |
[INFO] [stdout] 35 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> src/generics/mod.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |         y: T,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:35:14
[INFO] [stdout]    |
[INFO] [stdout] 35 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `z`
[INFO] [stdout]   --> src/generics/mod.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |         z: U,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:35:14
[INFO] [stdout]    |
[INFO] [stdout] 35 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `x`
[INFO] [stdout]   --> src/generics/mod.rs:62:9
[INFO] [stdout]    |
[INFO] [stdout] 62 |         x: Point<T>,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `Line` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:60:14
[INFO] [stdout]    |
[INFO] [stdout] 60 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> src/generics/mod.rs:63:9
[INFO] [stdout]    |
[INFO] [stdout] 63 |         y: Point<T>,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `Line` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/generics/mod.rs:60:14
[INFO] [stdout]    |
[INFO] [stdout] 60 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `name`
[INFO] [stdout]   --> src/lifecycle/mod.rs:33:9
[INFO] [stdout]    |
[INFO] [stdout] 33 |         name: &'a str, // 这是一个引用，引用了一个字符串，字符串本身有自己的生命周期
[INFO] [stdout]    |         ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `PersonM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/lifecycle/mod.rs:31:14
[INFO] [stdout]    |
[INFO] [stdout] 31 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Fruit`
[INFO] [stdout]  --> src/my_enum.rs:8:10
[INFO] [stdout]   |
[INFO] [stdout] 8 |     enum Fruit {
[INFO] [stdout]   |          ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Color`
[INFO] [stdout]   --> src/my_enum.rs:14:10
[INFO] [stdout]    |
[INFO] [stdout] 14 |     enum Color {
[INFO] [stdout]    |          ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `IPv6`
[INFO] [stdout]   --> src/my_enum.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 | /         IPv6(
[INFO] [stdout] 24 | |             u8,
[INFO] [stdout] 25 | |             u8,
[INFO] [stdout] 26 | |             u8,
[INFO] [stdout] ...  |
[INFO] [stdout] 39 | |             u8,
[INFO] [stdout] 40 | |         ),
[INFO] [stdout]    | |_________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `content`
[INFO] [stdout]   --> src/pointer_box/mod.rs:58:9
[INFO] [stdout]    |
[INFO] [stdout] 58 |         content: String,
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `Link` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/pointer_box/mod.rs:55:14
[INFO] [stdout]    |
[INFO] [stdout] 55 |     #[derive(Debug)]
[INFO] [stdout]    |              ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `tag`
[INFO] [stdout]    --> src/pointer_box/mod.rs:144:9
[INFO] [stdout]     |
[INFO] [stdout] 144 |         tag: String,
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: `Node` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    --> src/pointer_box/mod.rs:141:14
[INFO] [stdout]     |
[INFO] [stdout] 141 |     #[derive(Debug)]
[INFO] [stdout]     |              ^^^^^
[INFO] [stdout]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `name`
[INFO] [stdout]  --> src/str_type/mod.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     name: String,
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] note: `Student` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]  --> src/str_type/mod.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 | #[derive(Debug)]
[INFO] [stdout]   |          ^^^^^
[INFO] [stdout]   = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `show`
[INFO] [stdout]   --> src/traits/mod.rs:19:4
[INFO] [stdout]    |
[INFO] [stdout] 19 | fn show<T: std::fmt::Display>(a: T) {
[INFO] [stdout]    |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `age`
[INFO] [stdout]    --> src/traits/mod.rs:170:9
[INFO] [stdout]     |
[INFO] [stdout] 170 |         age: U,
[INFO] [stdout]     |         ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: `Person` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    --> src/traits/mod.rs:167:14
[INFO] [stdout]     |
[INFO] [stdout] 167 |     #[derive(Debug)]
[INFO] [stdout]     |              ^^^^^
[INFO] [stdout]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:169:5
[INFO] [stdout]     |
[INFO] [stdout] 169 |     pointer_box::pointer_box();
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:181:5
[INFO] [stdout]     |
[INFO] [stdout] 181 |     str_type::str_type();
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/function.rs:62:5
[INFO] [stdout]    |
[INFO] [stdout] 62 | /     thread::spawn(move || {
[INFO] [stdout] 63 | |         println!("{}", hello_message);
[INFO] [stdout] 64 | |     })
[INFO] [stdout] 65 | |     .join(); // join 除非子线程退出，不然主线程会一直去等待
[INFO] [stdout]    | |____________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 38 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 53.83s
[INFO] [stderr]   Executable unittests src/main.rs (/opt/rustwide/target/debug/deps/hello-8b2775e7d8e7ae04)
[INFO] running `Command { std: "docker" "inspect" "48f9b893f63affd0058693b3324fbddd45a78d7981cf61dd8fc0c37367cdd322", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "48f9b893f63affd0058693b3324fbddd45a78d7981cf61dd8fc0c37367cdd322", kill_on_drop: false }`
[INFO] [stdout] 48f9b893f63affd0058693b3324fbddd45a78d7981cf61dd8fc0c37367cdd322
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] c6f606b52f1114a9e86102f81f29b5610fc16628f823ba0eb7f5680dc8f4f149
[INFO] running `Command { std: "docker" "start" "-a" "c6f606b52f1114a9e86102f81f29b5610fc16628f823ba0eb7f5680dc8f4f149", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr] warning: unused import: `core::panic`
[INFO] [stderr]  --> src/error/mod.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use core::panic;
[INFO] [stderr]   |     ^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::thread::sleep`
[INFO] [stderr]  --> src/tiem/mod.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::thread::sleep;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `files`
[INFO] [stderr]    --> src/error/mod.rs:134:9
[INFO] [stderr]     |
[INFO] [stderr] 134 |     let files = file();
[INFO] [stderr]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_files`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `data`
[INFO] [stderr]    --> src/error/mod.rs:147:12
[INFO] [stderr]     |
[INFO] [stderr] 147 |         Ok(data) => {
[INFO] [stderr]     |            ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `data`
[INFO] [stderr]    --> src/error/mod.rs:164:12
[INFO] [stderr]     |
[INFO] [stderr] 164 |         Ok(data) => {}
[INFO] [stderr]     |            ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/error/mod.rs:36:24
[INFO] [stderr]    |
[INFO] [stderr] 36 |     fn divide_by_three(x: u32) -> u32 {
[INFO] [stderr]    |                        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `content`
[INFO] [stderr]    --> src/error/mod.rs:115:13
[INFO] [stderr]     |
[INFO] [stderr] 115 |         let content: &str = std::str::from_utf8(&data)?;
[INFO] [stderr]     |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_content`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `err`
[INFO] [stderr]   --> src/guess_number.rs:21:17
[INFO] [stderr]    |
[INFO] [stderr] 21 |             Err(err) => continue,
[INFO] [stderr]    |                 ^^^ help: if this is intentional, prefix it with an underscore: `_err`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `unit`
[INFO] [stderr]   --> src/my_struct.rs:37:9
[INFO] [stderr]    |
[INFO] [stderr] 37 |     let unit = Unit;
[INFO] [stderr]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_unit`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]   --> src/my_type_conversion.rs:28:9
[INFO] [stderr]    |
[INFO] [stderr] 28 |     let a = [0u8, 0u8, 0u8, 0u8];
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `box_arr`
[INFO] [stderr]    --> src/pointer_box/mod.rs:105:9
[INFO] [stderr]     |
[INFO] [stderr] 105 |     let box_arr = Box::new(arr); // arr这个数据已经放到堆上面了，这个放到堆上面的动作一定会发生内存拷贝的
[INFO] [stderr]     |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_box_arr`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `value2`
[INFO] [stderr]    --> src/traits/mod.rs:100:13
[INFO] [stderr]     |
[INFO] [stderr] 100 |         let value2 = 2;
[INFO] [stderr]     |             ^^^^^^ help: if this is intentional, prefix it with an underscore: `_value2`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `s_ref1`
[INFO] [stderr]    --> src/traits/mod.rs:193:9
[INFO] [stderr]     |
[INFO] [stderr] 193 |     let s_ref1 = &jack;
[INFO] [stderr]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_s_ref1`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `s_ref2`
[INFO] [stderr]    --> src/traits/mod.rs:194:9
[INFO] [stderr]     |
[INFO] [stderr] 194 |     let s_ref2 = &jack;
[INFO] [stderr]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_s_ref2`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/pointer_box/mod.rs:147:9
[INFO] [stderr]     |
[INFO] [stderr] 147 |     let mut n1 = Node {
[INFO] [stderr]     |         ----^^
[INFO] [stderr]     |         |
[INFO] [stderr]     |         help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `test_guess_number`
[INFO] [stderr]    --> src/main.rs:136:4
[INFO] [stderr]     |
[INFO] [stderr] 136 | fn test_guess_number() {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `test_use_key_words`
[INFO] [stderr]    --> src/main.rs:144:4
[INFO] [stderr]     |
[INFO] [stderr] 144 | fn test_use_key_words() {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `divide_by_three`
[INFO] [stderr]   --> src/error/mod.rs:36:8
[INFO] [stderr]    |
[INFO] [stderr] 36 |     fn divide_by_three(x: u32) -> u32 {
[INFO] [stderr]    |        ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `B`
[INFO] [stderr]    --> src/expressions.rs:123:9
[INFO] [stderr]     |
[INFO] [stderr] 123 |         B,
[INFO] [stderr]     |         ^
[INFO] [stderr]     |
[INFO] [stderr] note: `Alphabet` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]    --> src/expressions.rs:120:14
[INFO] [stderr]     |
[INFO] [stderr] 120 |     #[derive(Debug)]
[INFO] [stderr]     |              ^^^^^
[INFO] [stderr]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `B`
[INFO] [stderr]    --> src/expressions.rs:151:9
[INFO] [stderr]     |
[INFO] [stderr] 151 |         B,
[INFO] [stderr]     |         ^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `no_return`
[INFO] [stderr]    --> src/function.rs:117:9
[INFO] [stderr]     |
[INFO] [stderr] 117 |      fn no_return() {
[INFO] [stderr]     |         ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `x`
[INFO] [stderr]   --> src/generics/mod.rs:37:9
[INFO] [stderr]    |
[INFO] [stderr] 37 |         x: T,
[INFO] [stderr]    |         ^^^^
[INFO] [stderr]    |
[INFO] [stderr] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]   --> src/generics/mod.rs:35:14
[INFO] [stderr]    |
[INFO] [stderr] 35 |     #[derive(Debug)]
[INFO] [stderr]    |              ^^^^^
[INFO] [stderr]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `y`
[INFO] [stderr]   --> src/generics/mod.rs:38:9
[INFO] [stderr]    |
[INFO] [stderr] 38 |         y: T,
[INFO] [stderr]    |         ^^^^
[INFO] [stderr]    |
[INFO] [stderr] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]   --> src/generics/mod.rs:35:14
[INFO] [stderr]    |
[INFO] [stderr] 35 |     #[derive(Debug)]
[INFO] [stderr]    |              ^^^^^
[INFO] [stderr]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `z`
[INFO] [stderr]   --> src/generics/mod.rs:39:9
[INFO] [stderr]    |
[INFO] [stderr] 39 |         z: U,
[INFO] [stderr]    |         ^^^^
[INFO] [stderr]    |
[INFO] [stderr] note: `PointM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]   --> src/generics/mod.rs:35:14
[INFO] [stderr]    |
[INFO] [stderr] 35 |     #[derive(Debug)]
[INFO] [stderr]    |              ^^^^^
[INFO] [stderr]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `x`
[INFO] [stderr]   --> src/generics/mod.rs:62:9
[INFO] [stderr]    |
[INFO] [stderr] 62 |         x: Point<T>,
[INFO] [stderr]    |         ^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr] note: `Line` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]   --> src/generics/mod.rs:60:14
[INFO] [stderr]    |
[INFO] [stderr] 60 |     #[derive(Debug)]
[INFO] [stderr]    |              ^^^^^
[INFO] [stderr]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `y`
[INFO] [stderr]   --> src/generics/mod.rs:63:9
[INFO] [stderr]    |
[INFO] [stderr] 63 |         y: Point<T>,
[INFO] [stderr]    |         ^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr] note: `Line` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]   --> src/generics/mod.rs:60:14
[INFO] [stderr]    |
[INFO] [stderr] 60 |     #[derive(Debug)]
[INFO] [stderr]    |              ^^^^^
[INFO] [stderr]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `name`
[INFO] [stderr]   --> src/lifecycle/mod.rs:33:9
[INFO] [stderr]    |
[INFO] [stderr] 33 |         name: &'a str, // 这是一个引用，引用了一个字符串，字符串本身有自己的生命周期
[INFO] [stderr]    |         ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr] note: `PersonM` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]   --> src/lifecycle/mod.rs:31:14
[INFO] [stderr]    |
[INFO] [stderr] 31 |     #[derive(Debug)]
[INFO] [stderr]    |              ^^^^^
[INFO] [stderr]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `Fruit`
[INFO] [stderr]  --> src/my_enum.rs:8:10
[INFO] [stderr]   |
[INFO] [stderr] 8 |     enum Fruit {
[INFO] [stderr]   |          ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `Color`
[INFO] [stderr]   --> src/my_enum.rs:14:10
[INFO] [stderr]    |
[INFO] [stderr] 14 |     enum Color {
[INFO] [stderr]    |          ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `IPv6`
[INFO] [stderr]   --> src/my_enum.rs:23:9
[INFO] [stderr]    |
[INFO] [stderr] 23 | /         IPv6(
[INFO] [stderr] 24 | |             u8,
[INFO] [stderr] 25 | |             u8,
[INFO] [stderr] 26 | |             u8,
[INFO] [stderr] ...  |
[INFO] [stderr] 39 | |             u8,
[INFO] [stderr] 40 | |         ),
[INFO] [stderr]    | |_________^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `content`
[INFO] [stderr]   --> src/pointer_box/mod.rs:58:9
[INFO] [stderr]    |
[INFO] [stderr] 58 |         content: String,
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr] note: `Link` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]   --> src/pointer_box/mod.rs:55:14
[INFO] [stderr]    |
[INFO] [stderr] 55 |     #[derive(Debug)]
[INFO] [stderr]    |              ^^^^^
[INFO] [stderr]    = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `tag`
[INFO] [stderr]    --> src/pointer_box/mod.rs:144:9
[INFO] [stderr]     |
[INFO] [stderr] 144 |         tag: String,
[INFO] [stderr]     |         ^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr] note: `Node` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]    --> src/pointer_box/mod.rs:141:14
[INFO] [stderr]     |
[INFO] [stderr] 141 |     #[derive(Debug)]
[INFO] [stderr]     |              ^^^^^
[INFO] [stderr]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `name`
[INFO] [stderr]  --> src/str_type/mod.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     name: String,
[INFO] [stderr]   |     ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr] note: `Student` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]  --> src/str_type/mod.rs:5:10
[INFO] [stderr]   |
[INFO] [stderr] 5 | #[derive(Debug)]
[INFO] [stderr]   |          ^^^^^
[INFO] [stderr]   = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `show`
[INFO] [stderr]   --> src/traits/mod.rs:19:4
[INFO] [stderr]    |
[INFO] [stderr] 19 | fn show<T: std::fmt::Display>(a: T) {
[INFO] [stderr]    |    ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `age`
[INFO] [stderr]    --> src/traits/mod.rs:170:9
[INFO] [stderr]     |
[INFO] [stderr] 170 |         age: U,
[INFO] [stderr]     |         ^^^^^^
[INFO] [stderr]     |
[INFO] [stderr] note: `Person` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]    --> src/traits/mod.rs:167:14
[INFO] [stderr]     |
[INFO] [stderr] 167 |     #[derive(Debug)]
[INFO] [stderr]     |              ^^^^^
[INFO] [stderr]     = note: this warning originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]    --> src/main.rs:169:5
[INFO] [stderr]     |
[INFO] [stderr] 169 |     pointer_box::pointer_box();
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]    --> src/main.rs:181:5
[INFO] [stderr]     |
[INFO] [stderr] 181 |     str_type::str_type();
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> src/function.rs:62:5
[INFO] [stderr]    |
[INFO] [stderr] 62 | /     thread::spawn(move || {
[INFO] [stderr] 63 | |         println!("{}", hello_message);
[INFO] [stderr] 64 | |     })
[INFO] [stderr] 65 | |     .join(); // join 除非子线程退出，不然主线程会一直去等待
[INFO] [stderr]    | |____________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: `hello` (bin "hello" test) generated 38 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 21.54s
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/hello-8b2775e7d8e7ae04)
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "c6f606b52f1114a9e86102f81f29b5610fc16628f823ba0eb7f5680dc8f4f149", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c6f606b52f1114a9e86102f81f29b5610fc16628f823ba0eb7f5680dc8f4f149", kill_on_drop: false }`
[INFO] [stdout] c6f606b52f1114a9e86102f81f29b5610fc16628f823ba0eb7f5680dc8f4f149