[INFO] cloning repository https://github.com/flikeok/rust_example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/flikeok/rust_example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflikeok%2Frust_example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflikeok%2Frust_example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5d7f73bbef7cd9c4ac23591a14b013d2337004a7
[INFO] checking flikeok/rust_example against try#ae258e1fcbee4a062f5f3d869f06004d7cea088e for pr-135272
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflikeok%2Frust_example" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/flikeok/rust_example on toolchain ae258e1fcbee4a062f5f3d869f06004d7cea088e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ae258e1fcbee4a062f5f3d869f06004d7cea088e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/flikeok/rust_example
[INFO] finished tweaking git repo https://github.com/flikeok/rust_example
[INFO] tweaked toml for git repo https://github.com/flikeok/rust_example written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/flikeok/rust_example already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ae258e1fcbee4a062f5f3d869f06004d7cea088e" "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
[ERROR] error running command: no output for 300 seconds
[INFO] checking flikeok/rust_example against try#ae258e1fcbee4a062f5f3d869f06004d7cea088e for pr-135272
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflikeok%2Frust_example" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/flikeok/rust_example on toolchain ae258e1fcbee4a062f5f3d869f06004d7cea088e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ae258e1fcbee4a062f5f3d869f06004d7cea088e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/flikeok/rust_example
[INFO] finished tweaking git repo https://github.com/flikeok/rust_example
[INFO] tweaked toml for git repo https://github.com/flikeok/rust_example written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/flikeok/rust_example already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ae258e1fcbee4a062f5f3d869f06004d7cea088e" "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-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+ae258e1fcbee4a062f5f3d869f06004d7cea088e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3f62d6fd65b2a706837a8d3420d777151aa49bc975fa4aab4f0d75cebacc15ca
[INFO] running `Command { std: "docker" "start" "-a" "3f62d6fd65b2a706837a8d3420d777151aa49bc975fa4aab4f0d75cebacc15ca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3f62d6fd65b2a706837a8d3420d777151aa49bc975fa4aab4f0d75cebacc15ca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3f62d6fd65b2a706837a8d3420d777151aa49bc975fa4aab4f0d75cebacc15ca", kill_on_drop: false }`
[INFO] [stdout] 3f62d6fd65b2a706837a8d3420d777151aa49bc975fa4aab4f0d75cebacc15ca
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+ae258e1fcbee4a062f5f3d869f06004d7cea088e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 78e9ac91fb08ebe72569c7d600c029626e7f1e17f8fa7fb9947f5f22d6e25f62
[INFO] running `Command { std: "docker" "start" "-a" "78e9ac91fb08ebe72569c7d600c029626e7f1e17f8fa7fb9947f5f22d6e25f62", kill_on_drop: false }`
[INFO] [stderr]     Checking rust_example v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `CloseBox` and `OpenBox`
[INFO] [stdout]  --> src/ch10/structs.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use self::my::{CloseBox, OpenBox};
[INFO] [stdout]   |                ^^^^^^^^  ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `my::hello`
[INFO] [stdout]   --> src/ch10/uses.rs:20:5
[INFO] [stdout]    |
[INFO] [stdout] 20 | use my::hello;
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::str::FromStr`
[INFO] [stdout]  --> src/ch18/errors.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::str::FromStr;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `HashMap` and `HashSet`
[INFO] [stdout]  --> src/ch19/boxs.rs:1:24
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::collections::{HashMap, HashSet};
[INFO] [stdout]   |                        ^^^^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::rc::Rc`
[INFO] [stdout]  --> src/ch19/boxs.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::rc::Rc;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::sync::Arc`
[INFO] [stdout]  --> src/ch19/boxs.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::sync::Arc;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `JoinHandle` and `self`
[INFO] [stdout]  --> src/ch19/boxs.rs:4:19
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::thread::{self, JoinHandle};
[INFO] [stdout]   |                   ^^^^  ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::process::Command`
[INFO] [stdout]  --> src/ch19/cmds.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::process::Command;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `File`, `Read`, `SeekFrom`, `Seek`, `Write`, `os::unix::fs::FileExt`, `path::Path`, `remove_file`, and `str::from_utf8`
[INFO] [stdout]  --> src/ch19/files.rs:2:10
[INFO] [stdout]   |
[INFO] [stdout] 2 |     fs::{remove_file, File},
[INFO] [stdout]   |          ^^^^^^^^^^^  ^^^^
[INFO] [stdout] 3 |     io::{Read, Seek, SeekFrom, Write},
[INFO] [stdout]   |          ^^^^  ^^^^  ^^^^^^^^  ^^^^^
[INFO] [stdout] 4 |     os::unix::fs::FileExt,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 5 |     path::Path,
[INFO] [stdout]   |     ^^^^^^^^^^
[INFO] [stdout] 6 |     str::from_utf8,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `ffi::OsStr`, `path::Path`, `sync::mpsc`, and `thread`
[INFO] [stdout]  --> src/ch19/threads.rs:1:11
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{ffi::OsStr, path::Path, sync::mpsc, thread};
[INFO] [stdout]   |           ^^^^^^^^^^  ^^^^^^^^^^  ^^^^^^^^^^  ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fmt::format`
[INFO] [stdout]  --> src/ch6/to_strings.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::fmt::format;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::str::FromStr`
[INFO] [stdout]  --> src/ch18/errors.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::str::FromStr;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `JoinHandle`
[INFO] [stdout]  --> src/ch19/boxs.rs:4:25
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::thread::{self, JoinHandle};
[INFO] [stdout]   |                         ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `os::unix::fs::FileExt` and `str::from_utf8`
[INFO] [stdout]  --> src/ch19/files.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     os::unix::fs::FileExt,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 5 |     path::Path,
[INFO] [stdout] 6 |     str::from_utf8,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fmt::format`
[INFO] [stdout]  --> src/ch6/to_strings.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::fmt::format;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hello` is never used
[INFO] [stdout]  --> src/ch10/mods.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 |     fn hello() {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `pub_hello` is never used
[INFO] [stdout]  --> src/ch10/mods.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 |     pub fn pub_hello() {
[INFO] [stdout]   |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `indirect_access` is never used
[INFO] [stdout]  --> src/ch10/mods.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub fn indirect_access() {
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hello` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:15:12
[INFO] [stdout]    |
[INFO] [stdout] 15 |         fn hello() {
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `pub_hello` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:18:46
[INFO] [stdout]    |
[INFO] [stdout] 18 |         pub(in crate::ch10::mods::my_mod) fn pub_hello() {
[INFO] [stdout]    |                                              ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `self_hello` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:22:22
[INFO] [stdout]    |
[INFO] [stdout] 22 |         pub(self) fn self_hello() {
[INFO] [stdout]    |                      ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `super_hello` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:26:23
[INFO] [stdout]    |
[INFO] [stdout] 26 |         pub(super) fn super_hello() {
[INFO] [stdout]    |                       ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `call_super_in_nested` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:30:16
[INFO] [stdout]    |
[INFO] [stdout] 30 |         pub fn call_super_in_nested() {
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `call_crate_hello` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:34:23
[INFO] [stdout]    |
[INFO] [stdout] 34 |         pub(crate) fn call_crate_hello() {
[INFO] [stdout]    |                       ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `OpenBox` is never constructed
[INFO] [stdout]  --> src/ch10/structs.rs:4:16
[INFO] [stdout]   |
[INFO] [stdout] 4 |     pub struct OpenBox<T> {
[INFO] [stdout]   |                ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `CloseBox` is never constructed
[INFO] [stdout]  --> src/ch10/structs.rs:8:16
[INFO] [stdout]   |
[INFO] [stdout] 8 |     pub struct CloseBox<T> {
[INFO] [stdout]   |                ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new` and `print` are never used
[INFO] [stdout]   --> src/ch10/structs.rs:16:16
[INFO] [stdout]    |
[INFO] [stdout] 12 | /     impl<T> CloseBox<T>
[INFO] [stdout] 13 | |     where
[INFO] [stdout] 14 | |         T: std::fmt::Display,
[INFO] [stdout]    | |_____________________________- associated items in this implementation
[INFO] [stdout] 15 |       {
[INFO] [stdout] 16 |           pub fn new(t: T) -> Self {
[INFO] [stdout]    |                  ^^^
[INFO] [stdout] ...
[INFO] [stdout] 20 |           pub fn print(&self) {
[INFO] [stdout]    |                  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hello` is never used
[INFO] [stdout]  --> src/ch10/uses.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 |     pub fn hello() {
[INFO] [stdout]   |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `world` is never used
[INFO] [stdout]  --> src/ch10/uses.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 |     pub fn world() {
[INFO] [stdout]   |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hello` is never used
[INFO] [stdout]   --> src/ch10/uses.rs:10:16
[INFO] [stdout]    |
[INFO] [stdout] 10 |         pub fn hello() {
[INFO] [stdout]    |                ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `call_hello` is never used
[INFO] [stdout]   --> src/ch10/uses.rs:13:16
[INFO] [stdout]    |
[INFO] [stdout] 13 |         pub fn call_hello() {
[INFO] [stdout]    |                ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Animal` is never used
[INFO] [stdout]  --> src/ch16/traits.rs:1:7
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait Animal {
[INFO] [stdout]   |       ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Sheep` is never constructed
[INFO] [stdout]  --> src/ch16/traits.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Sheep {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new_sheep` is never used
[INFO] [stdout]   --> src/ch16/traits.rs:10:12
[INFO] [stdout]    |
[INFO] [stdout] 9  | impl Sheep {
[INFO] [stdout]    | ---------- associated function in this implementation
[INFO] [stdout] 10 |     pub fn new_sheep() -> Self {
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new_duck` is never used
[INFO] [stdout]   --> src/ch16/traits.rs:16:12
[INFO] [stdout]    |
[INFO] [stdout] 15 | impl Duck {
[INFO] [stdout]    | --------- associated function in this implementation
[INFO] [stdout] 16 |     pub fn new_duck() -> Self {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Duck` is never constructed
[INFO] [stdout]   --> src/ch16/traits.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 | struct Duck {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `random_animal` is never used
[INFO] [stdout]   --> src/ch16/traits.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn random_animal(i: i32) -> Box<dyn Animal> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `map_string` is never used
[INFO] [stdout]  --> src/ch18/maps.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn map_string(s: Option<String>) -> Option<usize> {
[INFO] [stdout]   |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `ParseIntResult` is never used
[INFO] [stdout]  --> src/ch18/results.rs:3:6
[INFO] [stdout]   |
[INFO] [stdout] 3 | type ParseIntResult<T> = Result<T, ParseIntError>;
[INFO] [stdout]   |      ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `two_plus` is never used
[INFO] [stdout]  --> src/ch18/results.rs:4:4
[INFO] [stdout]   |
[INFO] [stdout] 4 | fn two_plus(l: String, r: String) -> ParseIntResult<i32> {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `double_first` is never used
[INFO] [stdout]   --> src/ch18/results.rs:25:4
[INFO] [stdout]    |
[INFO] [stdout] 25 | fn double_first(vec: Vec<&str>) -> Option<Result<i32, ParseIntError>> {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Stu` is never constructed
[INFO] [stdout]  --> src/ch19/boxs.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Stu<'a> {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/ch19/boxs.rs:13:12
[INFO] [stdout]    |
[INFO] [stdout] 12 | impl<'a> Stu<'a> {
[INFO] [stdout]    | ---------------- associated function in this implementation
[INFO] [stdout] 13 |     pub fn new(s: &'a str, i: i32) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `a_plus_b` is never used
[INFO] [stdout]   --> src/ch19/boxs.rs:96:4
[INFO] [stdout]    |
[INFO] [stdout] 96 | fn a_plus_b(i: i32, j: i32) -> i32 {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `reverse` is never used
[INFO] [stdout]  --> src/ch2/tuple.rs:4:4
[INFO] [stdout]   |
[INFO] [stdout] 4 | fn reverse(left:i32,right:bool)->(bool,i32){
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Matrix` is never constructed
[INFO] [stdout]   --> src/ch2/tuple.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 24 | struct Matrix(f32, f32, f32, f32);
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `trans` is never used
[INFO] [stdout]   --> src/ch2/tuple.rs:36:8
[INFO] [stdout]    |
[INFO] [stdout] 33 | impl Matrix {
[INFO] [stdout]    | ----------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 36 |     fn trans(&self)->Self{
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `slice` is never used
[INFO] [stdout]   --> src/ch2/array.rs:12:4
[INFO] [stdout]    |
[INFO] [stdout] 12 | fn slice(s:&[i32]){
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> src/ch3/structs.rs:10:16
[INFO] [stdout]    |
[INFO] [stdout] 10 | pub struct Stu(i32,String);
[INFO] [stdout]    |            --- ^^^ ^^^^^^
[INFO] [stdout]    |            |
[INFO] [stdout]    |            fields in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing these fields
[INFO] [stdout]    = note: `Stu` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: static `MY_WORLD` is never used
[INFO] [stdout]  --> src/ch3/consts.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | static MY_WORLD:&'static str = "hello";
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `NUM` is never used
[INFO] [stdout]  --> src/ch3/consts.rs:2:7
[INFO] [stdout]   |
[INFO] [stdout] 2 | const NUM:i32 = 10;
[INFO] [stdout]   |       ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `MyInt` is never used
[INFO] [stdout]  --> src/ch5/types.rs:1:6
[INFO] [stdout]   |
[INFO] [stdout] 1 | type MyInt = i32;
[INFO] [stdout]   |      ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Color` is never used
[INFO] [stdout]   --> src/ch8/ifs.rs:42:6
[INFO] [stdout]    |
[INFO] [stdout] 42 | enum Color {
[INFO] [stdout]    |      ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `name` and `age` are never read
[INFO] [stdout]   --> src/ch8/ifs.rs:81:5
[INFO] [stdout]    |
[INFO] [stdout] 80 | pub struct Stu {
[INFO] [stdout]    |            --- fields in this struct
[INFO] [stdout] 81 |     name: String,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 82 |     age: i32,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `apply` is never used
[INFO] [stdout]    --> src/ch9/closure.rs:140:4
[INFO] [stdout]     |
[INFO] [stdout] 140 | fn apply<F>(f: F)
[INFO] [stdout]     |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `j`
[INFO] [stdout]   --> src/ch19/threads.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     for j in 0..10 {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_j`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `inferred_type` is never read
[INFO] [stdout]  --> src/ch2/num_type.rs:5:13
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let mut inferred_type = 12; // 根据下一行的赋值推断为 i64 类型
[INFO] [stdout]   |             ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `mut_able` is never read
[INFO] [stdout]  --> src/ch2/num_type.rs:9:13
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut mut_able = 12; // Mutable `i32`
[INFO] [stdout]   |             ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]   --> src/ch8/ifs.rs:75:9
[INFO] [stdout]    |
[INFO] [stdout] 71 |         value => {
[INFO] [stdout]    |         ----- matches any value
[INFO] [stdout] ...
[INFO] [stdout] 75 |         _ => 0,
[INFO] [stdout]    |         ^ no value can reach this
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hello` is never used
[INFO] [stdout]  --> src/ch10/mods.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 |     fn hello() {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `indirect_access` is never used
[INFO] [stdout]  --> src/ch10/mods.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub fn indirect_access() {
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hello` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:15:12
[INFO] [stdout]    |
[INFO] [stdout] 15 |         fn hello() {
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `pub_hello` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:18:46
[INFO] [stdout]    |
[INFO] [stdout] 18 |         pub(in crate::ch10::mods::my_mod) fn pub_hello() {
[INFO] [stdout]    |                                              ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `self_hello` is never used
[INFO] [stdout]   --> src/ch10/mods.rs:22:22
[INFO] [stdout]    |
[INFO] [stdout] 22 |         pub(self) fn self_hello() {
[INFO] [stdout]    |                      ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hello` is never used
[INFO] [stdout]   --> src/ch10/uses.rs:10:16
[INFO] [stdout]    |
[INFO] [stdout] 10 |         pub fn hello() {
[INFO] [stdout]    |                ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `call_hello` is never used
[INFO] [stdout]   --> src/ch10/uses.rs:13:16
[INFO] [stdout]    |
[INFO] [stdout] 13 |         pub fn call_hello() {
[INFO] [stdout]    |                ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `name` is never read
[INFO] [stdout]  --> src/ch16/traits.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Sheep {
[INFO] [stdout]   |        ----- field in this struct
[INFO] [stdout] 6 |     name: &'static str,
[INFO] [stdout]   |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `name` is never read
[INFO] [stdout]   --> src/ch16/traits.rs:28:5
[INFO] [stdout]    |
[INFO] [stdout] 27 | struct Duck {
[INFO] [stdout]    |        ---- field in this struct
[INFO] [stdout] 28 |     name: &'static str,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Color` is never used
[INFO] [stdout]   --> src/ch8/ifs.rs:42:6
[INFO] [stdout]    |
[INFO] [stdout] 42 | enum Color {
[INFO] [stdout]    |      ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `age` is never read
[INFO] [stdout]   --> src/ch8/ifs.rs:82:5
[INFO] [stdout]    |
[INFO] [stdout] 80 | pub struct Stu {
[INFO] [stdout]    |            --- field in this struct
[INFO] [stdout] 81 |     name: String,
[INFO] [stdout] 82 |     age: i32,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.22s
[INFO] running `Command { std: "docker" "inspect" "78e9ac91fb08ebe72569c7d600c029626e7f1e17f8fa7fb9947f5f22d6e25f62", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "78e9ac91fb08ebe72569c7d600c029626e7f1e17f8fa7fb9947f5f22d6e25f62", kill_on_drop: false }`
[INFO] [stdout] 78e9ac91fb08ebe72569c7d600c029626e7f1e17f8fa7fb9947f5f22d6e25f62
