[INFO] cloning repository https://github.com/alexniver/rustbook
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/alexniver/rustbook" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falexniver%2Frustbook", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falexniver%2Frustbook'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 7d31fd21558c2818c9fdc5b094adbb12ad878e02
[INFO] checking alexniver/rustbook/7d31fd21558c2818c9fdc5b094adbb12ad878e02 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falexniver%2Frustbook" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/alexniver/rustbook on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/alexniver/rustbook
[INFO] finished tweaking git repo https://github.com/alexniver/rustbook
[INFO] tweaked toml for git repo https://github.com/alexniver/rustbook written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/alexniver/rustbook 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" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: profiles for the non root package will be ignored, specify profiles at the workspace root:
[INFO] [stderr] package:   /workspace/builds/worker-6-tc1/source/chapter/ch-14-cargo/Cargo.toml
[INFO] [stderr] workspace: /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
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[INFO] [stdout] 1543a3e57045c0e4c63fe5c6dbac4bb1f2615627d18f39f7370240b53cc55e7f
[INFO] running `Command { std: "docker" "start" "-a" "1543a3e57045c0e4c63fe5c6dbac4bb1f2615627d18f39f7370240b53cc55e7f", kill_on_drop: false }`
[INFO] [stderr] warning: profiles for the non root package will be ignored, specify profiles at the workspace root:
[INFO] [stderr] package:   /opt/rustwide/workdir/chapter/ch-14-cargo/Cargo.toml
[INFO] [stderr] workspace: /opt/rustwide/workdir/Cargo.toml
[INFO] [stderr]    Compiling libc v0.2.137
[INFO] [stderr]     Checking ch-20-webserver v0.1.0 (/opt/rustwide/workdir/chapter/ch-20-webserver)
[INFO] [stderr]     Checking ch-15-05-refcell v0.1.0 (/opt/rustwide/workdir/chapter/ch-15-05-refcell)
[INFO] [stderr]     Checking ch-17-03-state v0.1.0 (/opt/rustwide/workdir/chapter/ch-17-03-state)
[INFO] [stderr]     Checking ch-07-03-mod v0.1.0 (/opt/rustwide/workdir/chapter/ch-07-03-mod)
[INFO] [stderr]     Checking ch-17-02-traitobj v0.1.0 (/opt/rustwide/workdir/chapter/ch-17-02-traitobj)
[INFO] [stderr]     Checking ch-07-02-crates v0.1.0 (/opt/rustwide/workdir/chapter/ch-07-02-crates)
[INFO] [stderr]     Checking ch-17-03-state-enum v0.1.0 (/opt/rustwide/workdir/chapter/ch-17-03-state-enum)
[INFO] [stderr]     Checking ch-14-cargo v0.1.0 (/opt/rustwide/workdir/chapter/ch-14-cargo)
[INFO] [stderr]     Checking ch-11-01-write-test v0.1.0 (/opt/rustwide/workdir/chapter/ch-11-01-write-test)
[INFO] [stderr]     Checking ch-12-grep v0.1.0 (/opt/rustwide/workdir/chapter/ch-12-grep)
[INFO] [stderr]     Checking rustbook v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking ch-11-03-test-org v0.1.0 (/opt/rustwide/workdir/chapter/ch-11-03-test-org)
[INFO] [stdout] warning: function `add_one` is never used
[INFO] [stdout]  --> chapter/ch-14-cargo/src/lib.rs:9:4
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn add_one(n: i32) -> i32 {
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Rect` is never constructed
[INFO] [stdout]  --> chapter/ch-11-01-write-test/src/lib.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Rect {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `can_hold` is never used
[INFO] [stdout]  --> chapter/ch-11-01-write-test/src/lib.rs:8:12
[INFO] [stdout]   |
[INFO] [stdout] 7 | impl Rect {
[INFO] [stdout]   | --------- method in this implementation
[INFO] [stdout] 8 |     pub fn can_hold(&self, other: Rect) -> bool {
[INFO] [stdout]   |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `value` is never read
[INFO] [stdout]   --> chapter/ch-11-01-write-test/src/lib.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub struct Guess {
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 23 |     value: i32,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> chapter/ch-11-01-write-test/src/lib.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 26 | impl Guess {
[INFO] [stdout]    | ---------- associated function in this implementation
[INFO] [stdout] 27 |     fn new(value: i32) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `error::Error` and `fs::read_to_string`
[INFO] [stdout]  --> chapter/ch-12-grep/src/main.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{env, error::Error, fs::read_to_string, process};
[INFO] [stdout]   |                ^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `error::Error` and `fs::read_to_string`
[INFO] [stdout]  --> chapter/ch-12-grep/src/main.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{env, error::Error, fs::read_to_string, process};
[INFO] [stdout]   |                ^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-09-02-result v0.1.0 (/opt/rustwide/workdir/chapter/ch-09-02-result)
[INFO] [stderr]     Checking ch-18-all-pattern v0.1.0 (/opt/rustwide/workdir/chapter/ch-18-1-all-pattern)
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapter/ch-15-05-refcell/src/main.rs:19:10
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout]    |     ---- ^^^^^^^^^^^^^^^^  ^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapter/ch-15-05-refcell/src/main.rs:19:10
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout]    |     ---- ^^^^^^^^^^^^^^^^  ^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-03-02-type v0.1.0 (/opt/rustwide/workdir/chapter/ch-03-02-type)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-03-03-fun v0.1.0 (/opt/rustwide/workdir/chapter/ch-03-03-fun)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Read`
[INFO] [stdout]  --> chapter/ch-09-02-result/src/main.rs:3:27
[INFO] [stdout]   |
[INFO] [stdout] 3 |     io::{self, ErrorKind, Read},
[INFO] [stdout]   |                           ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `openfile1` is never used
[INFO] [stdout]   --> chapter/ch-09-02-result/src/main.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn openfile1() -> File {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `openfile2` is never used
[INFO] [stdout]   --> chapter/ch-09-02-result/src/main.rs:38:4
[INFO] [stdout]    |
[INFO] [stdout] 38 | fn openfile2() -> File {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `readfile` is never used
[INFO] [stdout]   --> chapter/ch-09-02-result/src/main.rs:50:4
[INFO] [stdout]    |
[INFO] [stdout] 50 | fn readfile(filename: &str) -> Result<String, io::Error> {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-16-01-thread v0.1.0 (/opt/rustwide/workdir/chapter/ch-16-01-thread)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> chapter/ch-09-02-result/src/main.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     remove_file(FILE_NAME);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let _ = remove_file(FILE_NAME);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-05-03-struct-fn v0.1.0 (/opt/rustwide/workdir/chapter/ch-05-03-struct-fn)
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `time::Duration`
[INFO] [stdout]  --> chapter/ch-16-01-thread/src/main.rs:1:19
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{thread, time::Duration};
[INFO] [stdout]   |                   ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-15-03-drop v0.1.0 (/opt/rustwide/workdir/chapter/ch-15-03-drop)
[INFO] [stderr]     Checking ch-03-04-comment v0.1.0 (/opt/rustwide/workdir/chapter/ch-03-04-comment)
[INFO] [stdout] warning: unused variable: `result`
[INFO] [stdout]   --> chapter/ch-11-01-write-test/src/lib.rs:89:13
[INFO] [stdout]    |
[INFO] [stdout] 89 |         let result = Guess::new(101);
[INFO] [stdout]    |             ^^^^^^ help: if this is intentional, prefix it with an underscore: `_result`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `value` is never read
[INFO] [stdout]   --> chapter/ch-11-01-write-test/src/lib.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub struct Guess {
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 23 |     value: i32,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-18-3-pattern-syntax v0.1.0 (/opt/rustwide/workdir/chapter/ch-18-3-pattern-syntax)
[INFO] [stderr]     Checking ch-03-05-flow v0.1.0 (/opt/rustwide/workdir/chapter/ch-03-05-flow)
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-08-03-hashmap v0.1.0 (/opt/rustwide/workdir/chapter/ch-08-03-hashmap)
[INFO] [stderr]     Checking ch-04-03-slice v0.1.0 (/opt/rustwide/workdir/chapter/ch-04-03-slice)
[INFO] [stderr]     Checking ch-18-2-refutability v0.1.0 (/opt/rustwide/workdir/chapter/ch-18-2-refutability)
[INFO] [stdout] warning: multiple patterns overlap on their endpoints
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |         1..=5 => println!("less equal 5, bigger equal 1"),
[INFO] [stdout]    |         ----- this range overlaps on `5_i32`...
[INFO] [stdout] 30 |         5.. => println!("bigger than 5"),
[INFO] [stdout]    |         ^^^ ... with this range
[INFO] [stdout]    |
[INFO] [stdout]    = note: you likely meant to write mutually exclusive ranges
[INFO] [stdout]    = note: `#[warn(overlapping_range_endpoints)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 84 |         (a, b, _, _, e) => println!("{a}, {b}, _, _, {e}"),
[INFO] [stdout]    |         --------------- matches any value
[INFO] [stdout] 85 |         _ => println!("others"),
[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: unused variable: `s`
[INFO] [stdout]  --> chapter/ch-18-3-pattern-syntax/src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let s = match x {
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let y = 10;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `feet`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:68:11
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let ((feet, intch), Point { x, y }) = ((22, 33), Point { x: 333, y: 444 });
[INFO] [stdout]    |           ^^^^ help: if this is intentional, prefix it with an underscore: `_feet`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `intch`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:68:17
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let ((feet, intch), Point { x, y }) = ((22, 33), Point { x: 333, y: 444 });
[INFO] [stdout]    |                 ^^^^^ help: if this is intentional, prefix it with an underscore: `_intch`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:68:33
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let ((feet, intch), Point { x, y }) = ((22, 33), Point { x: 333, y: 444 });
[INFO] [stdout]    |                                 ^ help: try ignoring the field: `x: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:68:36
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let ((feet, intch), Point { x, y }) = ((22, 33), Point { x: 333, y: 444 });
[INFO] [stdout]    |                                    ^ help: try ignoring the field: `y: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-05-01-struct-def v0.1.0 (/opt/rustwide/workdir/chapter/ch-05-01-struct-def)
[INFO] [stdout] warning: variants `Quit`, `Move`, `Write`, and `ChangeColor` are never constructed
[INFO] [stdout]    --> chapter/ch-18-3-pattern-syntax/src/main.rs:156:5
[INFO] [stdout]     |
[INFO] [stdout] 155 | enum Message {
[INFO] [stdout]     |      ------- variants in this enum
[INFO] [stdout] 156 |     Quit,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 157 |     Move { x: i32, y: i32 },
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 158 |     Write(String),
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout] 159 |     ChangeColor(i32, i32, i32),
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Rgb` is never constructed
[INFO] [stdout]    --> chapter/ch-18-3-pattern-syntax/src/main.rs:165:5
[INFO] [stdout]     |
[INFO] [stdout] 163 | enum Color {
[INFO] [stdout]     |      ----- variant in this enum
[INFO] [stdout] 164 |     Hsv(i32, i32, i32),
[INFO] [stdout] 165 |     Rgb(i32, i32, i32),
[INFO] [stdout]     |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-01-02-hello-world v0.1.0 (/opt/rustwide/workdir/chapter/ch-01-02-hello-world)
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-01-03-hello-cargo v0.1.0 (/opt/rustwide/workdir/chapter/ch-01-03-hello-cargo)
[INFO] [stdout] warning: unused variable: `user2`
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let user2 = User {
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_user2`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `color`
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let color = Color(1, 1, 1);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_color`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `point`
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let point = Point(2., 3., 5.);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_point`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `always_equal`
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let always_equal = AlwaysEqual;
[INFO] [stdout]    |         ^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_always_equal`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `active`, `username`, and `sign_in_count` are never read
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 23 | struct User {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 24 |     active: bool,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 25 |     username: String,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout] 26 |     email: String,
[INFO] [stdout] 27 |     sign_in_count: u64,
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, and `2` are never read
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:30:14
[INFO] [stdout]    |
[INFO] [stdout] 30 | struct Color(u8, u8, u8);
[INFO] [stdout]    |        ----- ^^  ^^  ^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        fields in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing these fields
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, and `2` are never read
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:31:14
[INFO] [stdout]    |
[INFO] [stdout] 31 | struct Point(f32, f32, f32);
[INFO] [stdout]    |        ----- ^^^  ^^^  ^^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        fields in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing these fields
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `build_user` is never used
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:35:4
[INFO] [stdout]    |
[INFO] [stdout] 35 | fn build_user(username: String, email: String) -> User {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-10-02-traits v0.1.0 (/opt/rustwide/workdir/chapter/ch-10-02-traits)
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: irrefutable `if let` pattern
[INFO] [stdout]  --> chapter/ch-18-2-refutability/src/main.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 |     if let x = 5 {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this pattern will always match, so the `if let` is useless
[INFO] [stdout]   = help: consider replacing the `if let` with a `let`
[INFO] [stdout]   = note: `#[warn(irrefutable_let_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-16-02-chan v0.1.0 (/opt/rustwide/workdir/chapter/ch-16-02-chan)
[INFO] [stderr]     Checking ch-04-02-ref v0.1.0 (/opt/rustwide/workdir/chapter/ch-04-02-ref)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-06-03-iflet v0.1.0 (/opt/rustwide/workdir/chapter/ch-06-03-iflet)
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> chapter/ch-10-02-traits/src/main.rs:75:22
[INFO] [stdout]    |
[INFO] [stdout] 75 | pub fn some_fn<T, U>(t: &T, u: &U) -> f32
[INFO] [stdout]    |                      ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `u`
[INFO] [stdout]   --> chapter/ch-10-02-traits/src/main.rs:75:29
[INFO] [stdout]    |
[INFO] [stdout] 75 | pub fn some_fn<T, U>(t: &T, u: &U) -> f32
[INFO] [stdout]    |                             ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s1`
[INFO] [stdout]   --> chapter/ch-04-02-ref/src/main.rs:11:13
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let s1 = &mut s;
[INFO] [stdout]    |             ^^ help: if this is intentional, prefix it with an underscore: `_s1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-13-01-closures v0.1.0 (/opt/rustwide/workdir/chapter/ch-13-01-closures)
[INFO] [stderr]     Checking ch-10-03-lifetime v0.1.0 (/opt/rustwide/workdir/chapter/ch-10-03-lifetime)
[INFO] [stderr]     Checking ch-06-01-enum v0.1.0 (/opt/rustwide/workdir/chapter/ch-06-01-enum)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-05-02-struct-examp v0.1.0 (/opt/rustwide/workdir/chapter/ch-05-02-struct-examp)
[INFO] [stderr]     Checking ch-06-02-match v0.1.0 (/opt/rustwide/workdir/chapter/ch-06-02-match)
[INFO] [stderr]     Checking ch-15-02-deref v0.1.0 (/opt/rustwide/workdir/chapter/ch-15-02-deref)
[INFO] [stderr]     Checking ch-15-01-box v0.1.0 (/opt/rustwide/workdir/chapter/ch-15-01-box)
[INFO] [stderr]     Checking ch-08-02-utf8 v0.1.0 (/opt/rustwide/workdir/chapter/ch-08-02-utf8)
[INFO] [stderr]     Checking ch-16-03-mutex v0.1.0 (/opt/rustwide/workdir/chapter/ch-16-03-mutex)
[INFO] [stdout] warning: field `text` is never read
[INFO] [stdout]   --> chapter/ch-10-03-lifetime/src/main.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 23 | struct Item<'a> {
[INFO] [stdout]    |        ---- field in this struct
[INFO] [stdout] 24 |     text: &'a str,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Item` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-15-04-rc v0.1.0 (/opt/rustwide/workdir/chapter/ch-15-04-rc)
[INFO] [stdout] warning: unused variable: `list`
[INFO] [stdout]  --> chapter/ch-15-01-box/src/main.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let list = Cons(1, Box::new(Cons(2, Box::new(Cons(3, Box::new(Nil))))));
[INFO] [stdout]   |         ^^^^ help: if this is intentional, prefix it with an underscore: `_list`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapter/ch-15-01-box/src/main.rs:10:10
[INFO] [stdout]    |
[INFO] [stdout] 10 |     Cons(i32, Box<ConsList>),
[INFO] [stdout]    |     ---- ^^^  ^^^^^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 10 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]   --> chapter/ch-08-02-utf8/src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let hello = String::from("hello");
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `num` is never read
[INFO] [stdout]  --> chapter/ch-06-02-match/src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     num = plus_one(num);
[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 `none` is never read
[INFO] [stdout]  --> chapter/ch-06-02-match/src/main.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     none = plus_one(none);
[INFO] [stdout]   |     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Alaska` is never constructed
[INFO] [stdout]   --> chapter/ch-06-02-match/src/main.rs:30:5
[INFO] [stdout]    |
[INFO] [stdout] 28 | enum UsState {
[INFO] [stdout]    |      ------- variant in this enum
[INFO] [stdout] 29 |     Alabama,
[INFO] [stdout] 30 |     Alaska,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `UsState` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:19:9
[INFO] [stdout]    |
[INFO] [stdout] 19 |     let home = IpAddr::IPV4(127, 0, 0, 1);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `loop_back`
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let loop_back = IpAddr::IPV6(String::from("::1"));
[INFO] [stdout]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_loop_back`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, `2`, and `3` are never read
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:44:10
[INFO] [stdout]    |
[INFO] [stdout] 44 |     IPV4(u8, u8, u8, u8),
[INFO] [stdout]    |     ---- ^^  ^^  ^^  ^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 44 |     IPV4((), (), (), ()),
[INFO] [stdout]    |          ~~  ~~  ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:45:10
[INFO] [stdout]    |
[INFO] [stdout] 45 |     IPV6(String),
[INFO] [stdout]    |     ---- ^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 45 |     IPV6(()),
[INFO] [stdout]    |          ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `ipAddrKind` should have a snake case name
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:47:10
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn route(ipAddrKind: IpAddrKind) {
[INFO] [stdout]    |          ^^^^^^^^^^ help: convert the identifier to snake case: `ip_addr_kind`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Penny`, `Nickel`, and `Dime` are never constructed
[INFO] [stdout]   --> chapter/ch-06-02-match/src/main.rs:34:5
[INFO] [stdout]    |
[INFO] [stdout] 33 | enum Coin {
[INFO] [stdout]    |      ---- variants in this enum
[INFO] [stdout] 34 |     Penny,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 35 |     Nickel,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 36 |     Dime,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> chapter/ch-15-04-rc/src/main.rs:8:13
[INFO] [stdout]   |
[INFO] [stdout] 8 |         let b = Cons(6, Rc::clone(&a));
[INFO] [stdout]   |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> chapter/ch-15-04-rc/src/main.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let c = Cons(7, Rc::clone(&a));
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapter/ch-15-04-rc/src/main.rs:17:10
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Cons(i32, Rc<List>),
[INFO] [stdout]    |     ---- ^^^  ^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-04-01-own v0.1.0 (/opt/rustwide/workdir/chapter/ch-04-01-own)
[INFO] [stdout] warning: unused variable: `s1`
[INFO] [stdout]   --> chapter/ch-04-02-ref/src/main.rs:11:13
[INFO] [stdout]    |
[INFO] [stdout] 11 |         let s1 = &mut s;
[INFO] [stdout]    |             ^^ help: if this is intentional, prefix it with an underscore: `_s1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `text` is never read
[INFO] [stdout]   --> chapter/ch-10-03-lifetime/src/main.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 23 | struct Item<'a> {
[INFO] [stdout]    |        ---- field in this struct
[INFO] [stdout] 24 |     text: &'a str,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Item` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-03-01-var v0.1.0 (/opt/rustwide/workdir/chapter/ch-03-01-var)
[INFO] [stderr]     Checking ch-09-01-panic v0.1.0 (/opt/rustwide/workdir/chapter/ch-09-01-panic)
[INFO] [stdout] warning: unused variable: `spaces`
[INFO] [stdout]   --> chapter/ch-03-01-var/src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let spaces = spaces.len();
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_spaces`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::str::FromStr`
[INFO] [stdout]  --> chapter/ch-04-01-own/src/main.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] [stderr]     Checking ch-08-01-vec v0.1.0 (/opt/rustwide/workdir/chapter/ch-08-01-vec)
[INFO] [stderr]     Checking ch-17-01-obj v0.1.0 (/opt/rustwide/workdir/chapter/ch-17-01-obj)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]  --> chapter/ch-04-01-own/src/main.rs:5:13
[INFO] [stdout]   |
[INFO] [stdout] 5 |         let s = "hello";
[INFO] [stdout]   |             ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]   --> chapter/ch-04-01-own/src/main.rs:13:13
[INFO] [stdout]    |
[INFO] [stdout] 13 |         let s2 = s1;
[INFO] [stdout]    |             ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `list`
[INFO] [stdout]  --> chapter/ch-15-01-box/src/main.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let list = Cons(1, Box::new(Cons(2, Box::new(Cons(3, Box::new(Nil))))));
[INFO] [stdout]   |         ^^^^ help: if this is intentional, prefix it with an underscore: `_list`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapter/ch-15-01-box/src/main.rs:10:10
[INFO] [stdout]    |
[INFO] [stdout] 10 |     Cons(i32, Box<ConsList>),
[INFO] [stdout]    |     ---- ^^^  ^^^^^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 10 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `cell_arr`
[INFO] [stdout]   --> chapter/ch-08-01-vec/src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let cell_arr = vec![
[INFO] [stdout]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_cell_arr`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> chapter/ch-17-01-obj/src/main.rs:16:18
[INFO] [stdout]    |
[INFO] [stdout] 16 |             Some(v) => {
[INFO] [stdout]    |                  ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> chapter/ch-17-01-obj/src/main.rs:16:18
[INFO] [stdout]    |
[INFO] [stdout] 16 |             Some(v) => {
[INFO] [stdout]    |                  ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> chapter/ch-08-01-vec/src/main.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     Int(i32),
[INFO] [stdout]    |     --- ^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 36 |     Int(()),
[INFO] [stdout]    |         ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> chapter/ch-08-01-vec/src/main.rs:37:11
[INFO] [stdout]    |
[INFO] [stdout] 37 |     Float(f32),
[INFO] [stdout]    |     ----- ^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 37 |     Float(()),
[INFO] [stdout]    |           ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> chapter/ch-08-01-vec/src/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |     Str(String),
[INFO] [stdout]    |     --- ^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 38 |     Str(()),
[INFO] [stdout]    |         ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one` is never used
[INFO] [stdout]  --> chapter/ch-14-cargo/src/lib.rs:9:4
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn add_one(n: i32) -> i32 {
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `user2`
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let user2 = User {
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_user2`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `color`
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let color = Color(1, 1, 1);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_color`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `point`
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let point = Point(2., 3., 5.);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_point`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `always_equal`
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let always_equal = AlwaysEqual;
[INFO] [stdout]    |         ^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_always_equal`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `active`, `username`, and `sign_in_count` are never read
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 23 | struct User {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 24 |     active: bool,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 25 |     username: String,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout] 26 |     email: String,
[INFO] [stdout] 27 |     sign_in_count: u64,
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, and `2` are never read
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:30:14
[INFO] [stdout]    |
[INFO] [stdout] 30 | struct Color(u8, u8, u8);
[INFO] [stdout]    |        ----- ^^  ^^  ^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        fields in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing these fields
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, and `2` are never read
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:31:14
[INFO] [stdout]    |
[INFO] [stdout] 31 | struct Point(f32, f32, f32);
[INFO] [stdout]    |        ----- ^^^  ^^^  ^^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        fields in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing these fields
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `build_user` is never used
[INFO] [stdout]   --> chapter/ch-05-01-struct-def/src/main.rs:35:4
[INFO] [stdout]    |
[INFO] [stdout] 35 | fn build_user(username: String, email: String) -> User {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:19:9
[INFO] [stdout]    |
[INFO] [stdout] 19 |     let home = IpAddr::IPV4(127, 0, 0, 1);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `loop_back`
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let loop_back = IpAddr::IPV6(String::from("::1"));
[INFO] [stdout]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_loop_back`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, `2`, and `3` are never read
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:44:10
[INFO] [stdout]    |
[INFO] [stdout] 44 |     IPV4(u8, u8, u8, u8),
[INFO] [stdout]    |     ---- ^^  ^^  ^^  ^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 44 |     IPV4((), (), (), ()),
[INFO] [stdout]    |          ~~  ~~  ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:45:10
[INFO] [stdout]    |
[INFO] [stdout] 45 |     IPV6(String),
[INFO] [stdout]    |     ---- ^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 45 |     IPV6(()),
[INFO] [stdout]    |          ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `ipAddrKind` should have a snake case name
[INFO] [stdout]   --> chapter/ch-06-01-enum/src/main.rs:47:10
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn route(ipAddrKind: IpAddrKind) {
[INFO] [stdout]    |          ^^^^^^^^^^ help: convert the identifier to snake case: `ip_addr_kind`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: irrefutable `if let` pattern
[INFO] [stdout]  --> chapter/ch-18-2-refutability/src/main.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 |     if let x = 5 {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this pattern will always match, so the `if let` is useless
[INFO] [stdout]   = help: consider replacing the `if let` with a `let`
[INFO] [stdout]   = note: `#[warn(irrefutable_let_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]   --> chapter/ch-08-02-utf8/src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let hello = String::from("hello");
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Read`
[INFO] [stdout]  --> chapter/ch-09-02-result/src/main.rs:3:27
[INFO] [stdout]   |
[INFO] [stdout] 3 |     io::{self, ErrorKind, Read},
[INFO] [stdout]   |                           ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `openfile1` is never used
[INFO] [stdout]   --> chapter/ch-09-02-result/src/main.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn openfile1() -> File {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `openfile2` is never used
[INFO] [stdout]   --> chapter/ch-09-02-result/src/main.rs:38:4
[INFO] [stdout]    |
[INFO] [stdout] 38 | fn openfile2() -> File {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `readfile` is never used
[INFO] [stdout]   --> chapter/ch-09-02-result/src/main.rs:50:4
[INFO] [stdout]    |
[INFO] [stdout] 50 | fn readfile(filename: &str) -> Result<String, io::Error> {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> chapter/ch-09-02-result/src/main.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     remove_file(FILE_NAME);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let _ = remove_file(FILE_NAME);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> chapter/ch-10-02-traits/src/main.rs:75:22
[INFO] [stdout]    |
[INFO] [stdout] 75 | pub fn some_fn<T, U>(t: &T, u: &U) -> f32
[INFO] [stdout]    |                      ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `u`
[INFO] [stdout]   --> chapter/ch-10-02-traits/src/main.rs:75:29
[INFO] [stdout]    |
[INFO] [stdout] 75 | pub fn some_fn<T, U>(t: &T, u: &U) -> f32
[INFO] [stdout]    |                             ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-13-02-iter v0.1.0 (/opt/rustwide/workdir/chapter/ch-13-02-iter)
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-10-01-generic v0.1.0 (/opt/rustwide/workdir/chapter/ch-10-01-generic)
[INFO] [stdout] warning: unused import: `time::Duration`
[INFO] [stdout]  --> chapter/ch-16-01-thread/src/main.rs:1:19
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{thread, time::Duration};
[INFO] [stdout]   |                   ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> chapter/ch-15-04-rc/src/main.rs:8:13
[INFO] [stdout]   |
[INFO] [stdout] 8 |         let b = Cons(6, Rc::clone(&a));
[INFO] [stdout]   |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> chapter/ch-15-04-rc/src/main.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let c = Cons(7, Rc::clone(&a));
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]   --> chapter/ch-15-04-rc/src/main.rs:17:10
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Cons(i32, Rc<List>),
[INFO] [stdout]    |     ---- ^^^  ^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     fields in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Cons((), ()),
[INFO] [stdout]    |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ch-15-06-refcycle v0.1.0 (/opt/rustwide/workdir/chapter/ch-15-06-refcycle)
[INFO] [stdout] warning: unused variable: `cell_arr`
[INFO] [stdout]   --> chapter/ch-08-01-vec/src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let cell_arr = vec![
[INFO] [stdout]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_cell_arr`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `contents` should have an upper case name
[INFO] [stdout]   --> chapter/ch-12-grep/src/lib.rs:61:11
[INFO] [stdout]    |
[INFO] [stdout] 61 |     const contents: &str = "\
[INFO] [stdout]    |           ^^^^^^^^ help: convert the identifier to upper case: `CONTENTS`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_upper_case_globals)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> chapter/ch-08-01-vec/src/main.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     Int(i32),
[INFO] [stdout]    |     --- ^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 36 |     Int(()),
[INFO] [stdout]    |         ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> chapter/ch-08-01-vec/src/main.rs:37:11
[INFO] [stdout]    |
[INFO] [stdout] 37 |     Float(f32),
[INFO] [stdout]    |     ----- ^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 37 |     Float(()),
[INFO] [stdout]    |           ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> chapter/ch-08-01-vec/src/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |     Str(String),
[INFO] [stdout]    |     --- ^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 38 |     Str(()),
[INFO] [stdout]    |         ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value` and `children` are never read
[INFO] [stdout]   --> chapter/ch-15-06-refcycle/src/main.rs:38:5
[INFO] [stdout]    |
[INFO] [stdout] 37 | struct Node {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 38 |     value: i32,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 39 |     parent: RefCell<Weak<Node>>,
[INFO] [stdout] 40 |     children: RefCell<Vec<Rc<Node>>>,
[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]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::str::FromStr`
[INFO] [stdout]  --> chapter/ch-04-01-own/src/main.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 variable: `s`
[INFO] [stdout]  --> chapter/ch-04-01-own/src/main.rs:5:13
[INFO] [stdout]   |
[INFO] [stdout] 5 |         let s = "hello";
[INFO] [stdout]   |             ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]   --> chapter/ch-04-01-own/src/main.rs:13:13
[INFO] [stdout]    |
[INFO] [stdout] 13 |         let s2 = s1;
[INFO] [stdout]    |             ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `spaces`
[INFO] [stdout]   --> chapter/ch-03-01-var/src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let spaces = spaces.len();
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_spaces`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking getrandom v0.2.8
[INFO] [stdout] warning: value assigned to `num` is never read
[INFO] [stdout]  --> chapter/ch-06-02-match/src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     num = plus_one(num);
[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 `none` is never read
[INFO] [stdout]  --> chapter/ch-06-02-match/src/main.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     none = plus_one(none);
[INFO] [stdout]   |     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Alaska` is never constructed
[INFO] [stdout]   --> chapter/ch-06-02-match/src/main.rs:30:5
[INFO] [stdout]    |
[INFO] [stdout] 28 | enum UsState {
[INFO] [stdout]    |      ------- variant in this enum
[INFO] [stdout] 29 |     Alabama,
[INFO] [stdout] 30 |     Alaska,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `UsState` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Penny`, `Nickel`, and `Dime` are never constructed
[INFO] [stdout]   --> chapter/ch-06-02-match/src/main.rs:34:5
[INFO] [stdout]    |
[INFO] [stdout] 33 | enum Coin {
[INFO] [stdout]    |      ---- variants in this enum
[INFO] [stdout] 34 |     Penny,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 35 |     Nickel,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 36 |     Dime,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Shoe` is never constructed
[INFO] [stdout]   --> chapter/ch-13-02-iter/src/main.rs:51:8
[INFO] [stdout]    |
[INFO] [stdout] 51 | struct Shoe {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `shoes_in_size` is never used
[INFO] [stdout]   --> chapter/ch-13-02-iter/src/main.rs:56:4
[INFO] [stdout]    |
[INFO] [stdout] 56 | fn shoes_in_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: multiple patterns overlap on their endpoints
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |         1..=5 => println!("less equal 5, bigger equal 1"),
[INFO] [stdout]    |         ----- this range overlaps on `5_i32`...
[INFO] [stdout] 30 |         5.. => println!("bigger than 5"),
[INFO] [stdout]    |         ^^^ ... with this range
[INFO] [stdout]    |
[INFO] [stdout]    = note: you likely meant to write mutually exclusive ranges
[INFO] [stdout]    = note: `#[warn(overlapping_range_endpoints)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 84 |         (a, b, _, _, e) => println!("{a}, {b}, _, _, {e}"),
[INFO] [stdout]    |         --------------- matches any value
[INFO] [stdout] 85 |         _ => println!("others"),
[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: unused variable: `s`
[INFO] [stdout]  --> chapter/ch-18-3-pattern-syntax/src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let s = match x {
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let y = 10;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `feet`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:68:11
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let ((feet, intch), Point { x, y }) = ((22, 33), Point { x: 333, y: 444 });
[INFO] [stdout]    |           ^^^^ help: if this is intentional, prefix it with an underscore: `_feet`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `intch`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:68:17
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let ((feet, intch), Point { x, y }) = ((22, 33), Point { x: 333, y: 444 });
[INFO] [stdout]    |                 ^^^^^ help: if this is intentional, prefix it with an underscore: `_intch`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:68:33
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let ((feet, intch), Point { x, y }) = ((22, 33), Point { x: 333, y: 444 });
[INFO] [stdout]    |                                 ^ help: try ignoring the field: `x: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> chapter/ch-18-3-pattern-syntax/src/main.rs:68:36
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let ((feet, intch), Point { x, y }) = ((22, 33), Point { x: 333, y: 444 });
[INFO] [stdout]    |                                    ^ help: try ignoring the field: `y: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value` and `children` are never read
[INFO] [stdout]   --> chapter/ch-15-06-refcycle/src/main.rs:38:5
[INFO] [stdout]    |
[INFO] [stdout] 37 | struct Node {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 38 |     value: i32,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 39 |     parent: RefCell<Weak<Node>>,
[INFO] [stdout] 40 |     children: RefCell<Vec<Rc<Node>>>,
[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]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Quit`, `Move`, `Write`, and `ChangeColor` are never constructed
[INFO] [stdout]    --> chapter/ch-18-3-pattern-syntax/src/main.rs:156:5
[INFO] [stdout]     |
[INFO] [stdout] 155 | enum Message {
[INFO] [stdout]     |      ------- variants in this enum
[INFO] [stdout] 156 |     Quit,
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 157 |     Move { x: i32, y: i32 },
[INFO] [stdout]     |     ^^^^
[INFO] [stdout] 158 |     Write(String),
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout] 159 |     ChangeColor(i32, i32, i32),
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Rgb` is never constructed
[INFO] [stdout]    --> chapter/ch-18-3-pattern-syntax/src/main.rs:165:5
[INFO] [stdout]     |
[INFO] [stdout] 163 | enum Color {
[INFO] [stdout]     |      ----- variant in this enum
[INFO] [stdout] 164 |     Hsv(i32, i32, i32),
[INFO] [stdout] 165 |     Rgb(i32, i32, i32),
[INFO] [stdout]     |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking ch-02-guess v0.1.0 (/opt/rustwide/workdir/chapter/ch-02-guess)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 7.85s
[INFO] running `Command { std: "docker" "inspect" "1543a3e57045c0e4c63fe5c6dbac4bb1f2615627d18f39f7370240b53cc55e7f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1543a3e57045c0e4c63fe5c6dbac4bb1f2615627d18f39f7370240b53cc55e7f", kill_on_drop: false }`
[INFO] [stdout] 1543a3e57045c0e4c63fe5c6dbac4bb1f2615627d18f39f7370240b53cc55e7f