[INFO] cloning repository https://github.com/CarlosLaraFP/rust-book
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/CarlosLaraFP/rust-book" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCarlosLaraFP%2Frust-book", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCarlosLaraFP%2Frust-book'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 18936fd9d0997a70166eb60858ec610172836863
[INFO] checking CarlosLaraFP/rust-book against master#507271bc119683008ec719ecee48814e8ac86c65 for pr-146440
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCarlosLaraFP%2Frust-book" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/CarlosLaraFP/rust-book
[INFO] finished tweaking git repo https://github.com/CarlosLaraFP/rust-book
[INFO] tweaked toml for git repo https://github.com/CarlosLaraFP/rust-book written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/CarlosLaraFP/rust-book on toolchain 507271bc119683008ec719ecee48814e8ac86c65
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+507271bc119683008ec719ecee48814e8ac86c65" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/CarlosLaraFP/rust-book 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" "+507271bc119683008ec719ecee48814e8ac86c65" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded libc v0.2.145
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+507271bc119683008ec719ecee48814e8ac86c65" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ac92f8a1a9e78f77efe7a933fc2f88bd1329fe39508b45b0538e6ed3cba760b5
[INFO] running `Command { std: "docker" "start" "-a" "ac92f8a1a9e78f77efe7a933fc2f88bd1329fe39508b45b0538e6ed3cba760b5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ac92f8a1a9e78f77efe7a933fc2f88bd1329fe39508b45b0538e6ed3cba760b5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ac92f8a1a9e78f77efe7a933fc2f88bd1329fe39508b45b0538e6ed3cba760b5", kill_on_drop: false }`
[INFO] [stdout] ac92f8a1a9e78f77efe7a933fc2f88bd1329fe39508b45b0538e6ed3cba760b5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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_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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+507271bc119683008ec719ecee48814e8ac86c65" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9e13b9b5c7d1215ab3111656fd08cd04d73e5431c79bb639c371a1279ecb9885
[INFO] running `Command { std: "docker" "start" "-a" "9e13b9b5c7d1215ab3111656fd08cd04d73e5431c79bb639c371a1279ecb9885", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.145
[INFO] [stderr]    Compiling proc-macro2 v1.0.66
[INFO] [stderr]    Compiling anyhow v1.0.71
[INFO] [stderr]     Checking hello_macro v0.1.0 (/opt/rustwide/workdir/hello_macro)
[INFO] [stderr]    Compiling quote v1.0.32
[INFO] [stderr]    Compiling syn v2.0.27
[INFO] [stderr]     Checking getrandom v0.2.9
[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]    Compiling hello_macro_derive v0.1.0 (/opt/rustwide/workdir/hello_macro_derive)
[INFO] [stderr]     Checking rust-book v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::collections::*`
[INFO] [stdout]   --> src/lib.rs:45:5
[INFO] [stdout]    |
[INFO] [stdout] 45 | use std::collections::*; // glob operator
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Write` and `self`
[INFO] [stdout]   --> src/lib.rs:47:15
[INFO] [stdout]    |
[INFO] [stdout] 47 | use std::io::{self, Write}; // brings std::io and std::io::Write into scope
[INFO] [stdout]    |               ^^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::*`
[INFO] [stdout]   --> src/lib.rs:45:5
[INFO] [stdout]    |
[INFO] [stdout] 45 | use std::collections::*; // glob operator
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Write` and `self`
[INFO] [stdout]   --> src/lib.rs:47:15
[INFO] [stdout]    |
[INFO] [stdout] 47 | use std::io::{self, Write}; // brings std::io and std::io::Write into scope
[INFO] [stdout]    |               ^^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]    --> src/oop.rs:157:27
[INFO] [stdout]     |
[INFO] [stdout] 157 |     fn content<'a>(&self, post: &'a Post) -> &'a str { "" }
[INFO] [stdout]     |                           ^^^^ help: if this is intentional, prefix it with an underscore: `_post`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `order1`
[INFO] [stdout]    --> src/lib.rs:109:9
[INFO] [stdout]     |
[INFO] [stdout] 109 |     let order1 = back_of_house::Appetizer::Soup;
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_order1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `order2`
[INFO] [stdout]    --> src/lib.rs:110:9
[INFO] [stdout]     |
[INFO] [stdout] 110 |     let order2 = back_of_house::Appetizer::Salad;
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_order2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c1`
[INFO] [stdout]    --> src/lib.rs:182:16
[INFO] [stdout]     |
[INFO] [stdout] 182 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]     |                ^^ help: if this is intentional, prefix it with an underscore: `_c1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c2`
[INFO] [stdout]    --> src/lib.rs:182:34
[INFO] [stdout]     |
[INFO] [stdout] 182 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]     |                                  ^^ help: if this is intentional, prefix it with an underscore: `_c2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `deliver_order` is never used
[INFO] [stdout]    --> src/lib.rs:148:4
[INFO] [stdout]     |
[INFO] [stdout] 148 | fn deliver_order() {}
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `function1` is never used
[INFO] [stdout]    --> src/lib.rs:153:4
[INFO] [stdout]     |
[INFO] [stdout] 153 | fn function1() -> fmt::Result {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `function2` is never used
[INFO] [stdout]    --> src/lib.rs:157:4
[INFO] [stdout]     |
[INFO] [stdout] 157 | fn function2() -> IoResult<()> {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `seat_at_table` is never used
[INFO] [stdout]  --> src/front_of_house/hosting.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn seat_at_table() {}
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `take_order` is never used
[INFO] [stdout]  --> src/front_of_house/serving.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn take_order() {}
[INFO] [stdout]   |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `serve_order` is never used
[INFO] [stdout]  --> src/front_of_house/serving.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn serve_order() {}
[INFO] [stdout]   |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `take_payment` is never used
[INFO] [stdout]  --> src/front_of_house/serving.rs:5:4
[INFO] [stdout]   |
[INFO] [stdout] 5 | fn take_payment() {}
[INFO] [stdout]   |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `greeting` is never used
[INFO] [stdout]    --> src/unit_tests.rs:118:8
[INFO] [stdout]     |
[INFO] [stdout] 118 | pub fn greeting(name: &str) -> String {
[INFO] [stdout]     |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_two` is never used
[INFO] [stdout]    --> src/unit_tests.rs:123:4
[INFO] [stdout]     |
[INFO] [stdout] 123 | fn add_two(a: i32) -> i32 {
[INFO] [stdout]     |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Shoe` is never constructed
[INFO] [stdout]  --> src/shoes.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Shoe {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `shoes_in_size` is never used
[INFO] [stdout]  --> src/shoes.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn shoes_in_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `seasonal_fruit` is never read
[INFO] [stdout]    --> src/lib.rs:116:9
[INFO] [stdout]     |
[INFO] [stdout] 114 |     pub struct Breakfast {
[INFO] [stdout]     |                --------- field in this struct
[INFO] [stdout] 115 |         pub toast: String,
[INFO] [stdout] 116 |         seasonal_fruit: String,
[INFO] [stdout]     |         ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fix_incorrect_order` is never used
[INFO] [stdout]    --> src/lib.rs:140:8
[INFO] [stdout]     |
[INFO] [stdout] 140 |     fn fix_incorrect_order() {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `cook_order` is never used
[INFO] [stdout]    --> src/lib.rs:145:8
[INFO] [stdout]     |
[INFO] [stdout] 145 |     fn cook_order() {}
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]    --> src/oop.rs:157:27
[INFO] [stdout]     |
[INFO] [stdout] 157 |     fn content<'a>(&self, post: &'a Post) -> &'a str { "" }
[INFO] [stdout]     |                           ^^^^ help: if this is intentional, prefix it with an underscore: `_post`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `order1`
[INFO] [stdout]    --> src/lib.rs:109:9
[INFO] [stdout]     |
[INFO] [stdout] 109 |     let order1 = back_of_house::Appetizer::Soup;
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_order1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `order2`
[INFO] [stdout]    --> src/lib.rs:110:9
[INFO] [stdout]     |
[INFO] [stdout] 110 |     let order2 = back_of_house::Appetizer::Salad;
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_order2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c1`
[INFO] [stdout]    --> src/lib.rs:182:16
[INFO] [stdout]     |
[INFO] [stdout] 182 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]     |                ^^ help: if this is intentional, prefix it with an underscore: `_c1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c2`
[INFO] [stdout]    --> src/lib.rs:182:34
[INFO] [stdout]     |
[INFO] [stdout] 182 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]     |                                  ^^ help: if this is intentional, prefix it with an underscore: `_c2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `deliver_order` is never used
[INFO] [stdout]    --> src/lib.rs:148:4
[INFO] [stdout]     |
[INFO] [stdout] 148 | fn deliver_order() {}
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `function1` is never used
[INFO] [stdout]    --> src/lib.rs:153:4
[INFO] [stdout]     |
[INFO] [stdout] 153 | fn function1() -> fmt::Result {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `function2` is never used
[INFO] [stdout]    --> src/lib.rs:157:4
[INFO] [stdout]     |
[INFO] [stdout] 157 | fn function2() -> IoResult<()> {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `seat_at_table` is never used
[INFO] [stdout]  --> src/front_of_house/hosting.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn seat_at_table() {}
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `take_order` is never used
[INFO] [stdout]  --> src/front_of_house/serving.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn take_order() {}
[INFO] [stdout]   |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `serve_order` is never used
[INFO] [stdout]  --> src/front_of_house/serving.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn serve_order() {}
[INFO] [stdout]   |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `take_payment` is never used
[INFO] [stdout]  --> src/front_of_house/serving.rs:5:4
[INFO] [stdout]   |
[INFO] [stdout] 5 | fn take_payment() {}
[INFO] [stdout]   |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `seasonal_fruit` is never read
[INFO] [stdout]    --> src/lib.rs:116:9
[INFO] [stdout]     |
[INFO] [stdout] 114 |     pub struct Breakfast {
[INFO] [stdout]     |                --------- field in this struct
[INFO] [stdout] 115 |         pub toast: String,
[INFO] [stdout] 116 |         seasonal_fruit: String,
[INFO] [stdout]     |         ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fix_incorrect_order` is never used
[INFO] [stdout]    --> src/lib.rs:140:8
[INFO] [stdout]     |
[INFO] [stdout] 140 |     fn fix_incorrect_order() {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `cook_order` is never used
[INFO] [stdout]    --> src/lib.rs:145:8
[INFO] [stdout]     |
[INFO] [stdout] 145 |     fn cook_order() {}
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `rust_book::shoes::*`
[INFO] [stdout]   --> src/main.rs:31:5
[INFO] [stdout]    |
[INFO] [stdout] 31 | use rust_book::shoes::*;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `rust_book::shoes::*`
[INFO] [stdout]   --> src/main.rs:31:5
[INFO] [stdout]    |
[INFO] [stdout] 31 | use rust_book::shoes::*;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:421:9
[INFO] [stdout]     |
[INFO] [stdout] 421 |     let mut s = String::new();
[INFO] [stdout]     |         ----^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:72:10
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let (x, y, z) = tup;
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]   --> src/main.rs:72:16
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let (x, y, z) = tup;
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `five_hundred`
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let five_hundred = x.0;
[INFO] [stdout]    |         ^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_five_hundred`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `six_point_four`
[INFO] [stdout]   --> src/main.rs:80:9
[INFO] [stdout]    |
[INFO] [stdout] 80 |     let six_point_four = x.1;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_six_point_four`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `one`
[INFO] [stdout]   --> src/main.rs:82:9
[INFO] [stdout]    |
[INFO] [stdout] 82 |     let one = x.2;
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_one`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:185:9
[INFO] [stdout]     |
[INFO] [stdout] 185 |     let y = x;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> src/main.rs:201:13
[INFO] [stdout]     |
[INFO] [stdout] 201 |         let r1 = &mut s;
[INFO] [stdout]     |             ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r2`
[INFO] [stdout]    --> src/main.rs:204:9
[INFO] [stdout]     |
[INFO] [stdout] 204 |     let r2 = &mut s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_r2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:421:9
[INFO] [stdout]     |
[INFO] [stdout] 421 |     let mut s = String::new();
[INFO] [stdout]     |         ----^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> src/main.rs:208:9
[INFO] [stdout]     |
[INFO] [stdout] 208 |     let r1 = &s; // no problem
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r2`
[INFO] [stdout]    --> src/main.rs:209:9
[INFO] [stdout]     |
[INFO] [stdout] 209 |     let r2 = &s; // no problem
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_r2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `slice`
[INFO] [stdout]    --> src/main.rs:233:9
[INFO] [stdout]     |
[INFO] [stdout] 233 |     let slice = &s[..];
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_slice`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]    --> src/main.rs:240:9
[INFO] [stdout]     |
[INFO] [stdout] 240 |     let word = first_word(&s);
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `black`
[INFO] [stdout]    --> src/main.rs:271:9
[INFO] [stdout]     |
[INFO] [stdout] 271 |     let black = Color(0, 0, 0);
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_black`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `subject`
[INFO] [stdout]    --> src/main.rs:272:9
[INFO] [stdout]     |
[INFO] [stdout] 272 |     let subject = AlwaysEqual;
[INFO] [stdout]     |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_subject`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_number`
[INFO] [stdout]    --> src/main.rs:315:9
[INFO] [stdout]     |
[INFO] [stdout] 315 |     let some_number = Some(5);
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_char`
[INFO] [stdout]    --> src/main.rs:316:9
[INFO] [stdout]     |
[INFO] [stdout] 316 |     let some_char = Some('e');
[INFO] [stdout]     |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_char`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `absent_number`
[INFO] [stdout]    --> src/main.rs:317:9
[INFO] [stdout]     |
[INFO] [stdout] 317 |     let absent_number: Option<i32> = None;
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_absent_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:369:9
[INFO] [stdout]     |
[INFO] [stdout] 369 |     let v: Vec<i32> = Vec::new();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:370:9
[INFO] [stdout]     |
[INFO] [stdout] 370 |     let v = vec![1, 2, 3];
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `row`
[INFO] [stdout]    --> src/main.rs:410:9
[INFO] [stdout]     |
[INFO] [stdout] 410 |     let row = vec![
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_row`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:421:9
[INFO] [stdout]     |
[INFO] [stdout] 421 |     let mut s = String::new();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:425:9
[INFO] [stdout]     |
[INFO] [stdout] 425 |     let s = data.to_string();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:428:9
[INFO] [stdout]     |
[INFO] [stdout] 428 |     let s = "initial contents".to_string();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:430:9
[INFO] [stdout]     |
[INFO] [stdout] 430 |     let s = String::from("initial contents");
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:433:9
[INFO] [stdout]     |
[INFO] [stdout] 433 |     let hello = String::from("السلام عليكم");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:434:9
[INFO] [stdout]     |
[INFO] [stdout] 434 |     let hello = String::from("Dobrý den");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:435:9
[INFO] [stdout]     |
[INFO] [stdout] 435 |     let hello = String::from("Hello");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:436:9
[INFO] [stdout]     |
[INFO] [stdout] 436 |     let hello = String::from("שָׁלוֹם");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:437:9
[INFO] [stdout]     |
[INFO] [stdout] 437 |     let hello = String::from("नमस्ते");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:438:9
[INFO] [stdout]     |
[INFO] [stdout] 438 |     let hello = String::from("こんにちは");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:439:9
[INFO] [stdout]     |
[INFO] [stdout] 439 |     let hello = String::from("안녕하세요");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:440:9
[INFO] [stdout]     |
[INFO] [stdout] 440 |     let hello = String::from("你好");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:441:9
[INFO] [stdout]     |
[INFO] [stdout] 441 |     let hello = String::from("Olá");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:442:9
[INFO] [stdout]     |
[INFO] [stdout] 442 |     let hello = String::from("Hola");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:451:9
[INFO] [stdout]     |
[INFO] [stdout] 451 |     let s = &hello[0..4];
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> src/main.rs:481:9
[INFO] [stdout]     |
[INFO] [stdout] 481 |     let s3 = s1 + &s2; // note s1 has been moved here and can no longer be used
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:487:9
[INFO] [stdout]     |
[INFO] [stdout] 487 |     let s = format!("{s1}-{s2}-{s3}");
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> src/main.rs:522:9
[INFO] [stdout]     |
[INFO] [stdout] 522 |     let x = scores
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:526:9
[INFO] [stdout]     |
[INFO] [stdout] 526 |     let y = scores
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `greeting_file`
[INFO] [stdout]    --> src/main.rs:554:9
[INFO] [stdout]     |
[INFO] [stdout] 554 |     let greeting_file = match File::open("hello.txt") {
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_greeting_file`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `greeting_file`
[INFO] [stdout]    --> src/main.rs:568:9
[INFO] [stdout]     |
[INFO] [stdout] 568 |     let greeting_file = File::open("hello.txt").unwrap_or_else(|error| {
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_greeting_file`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:72:10
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let (x, y, z) = tup;
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `greeting_file`
[INFO] [stdout]    --> src/main.rs:586:9
[INFO] [stdout]     |
[INFO] [stdout] 586 |     let greeting_file = std::fs::read_to_string("hello.txt")?;
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_greeting_file`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]    --> src/main.rs:588:9
[INFO] [stdout]     |
[INFO] [stdout] 588 |     let home: std::net::IpAddr = "127.0.0.1"
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/main.rs:641:9
[INFO] [stdout]     |
[INFO] [stdout] 641 |     let i = ImportantExcerpt {
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:651:9
[INFO] [stdout]     |
[INFO] [stdout] 651 |     let s: &'static str = "I have a static lifetime.";
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]   --> src/main.rs:72:16
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let (x, y, z) = tup;
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `expensive_closure`
[INFO] [stdout]    --> src/main.rs:671:9
[INFO] [stdout]     |
[INFO] [stdout] 671 |     let expensive_closure = |num: u32| -> u32 {
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_expensive_closure`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `five_hundred`
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let five_hundred = x.0;
[INFO] [stdout]    |         ^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_five_hundred`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `add_one_v2`
[INFO] [stdout]    --> src/main.rs:680:9
[INFO] [stdout]     |
[INFO] [stdout] 680 |     let add_one_v2 = |x: u32| -> u32 { x + 1 };
[INFO] [stdout]     |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_add_one_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `six_point_four`
[INFO] [stdout]   --> src/main.rs:80:9
[INFO] [stdout]    |
[INFO] [stdout] 80 |     let six_point_four = x.1;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_six_point_four`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> src/main.rs:821:9
[INFO] [stdout]     |
[INFO] [stdout] 821 |     let b = Cons(Rc::new(RefCell::new(3)), Rc::clone(&a));
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `one`
[INFO] [stdout]   --> src/main.rs:82:9
[INFO] [stdout]    |
[INFO] [stdout] 82 |     let one = x.2;
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_one`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> src/main.rs:822:9
[INFO] [stdout]     |
[INFO] [stdout] 822 |     let c = Cons(Rc::new(RefCell::new(4)), Rc::clone(&a));
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:185:9
[INFO] [stdout]     |
[INFO] [stdout] 185 |     let y = x;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> src/main.rs:827:9
[INFO] [stdout]     |
[INFO] [stdout] 827 |     let b = Cons(Rc::new(RefCell::new(3)), Rc::clone(&a));
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> src/main.rs:201:13
[INFO] [stdout]     |
[INFO] [stdout] 201 |         let r1 = &mut s;
[INFO] [stdout]     |             ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> src/main.rs:831:13
[INFO] [stdout]     |
[INFO] [stdout] 831 |         let c = Cons(Rc::new(RefCell::new(4)), Rc::clone(&a));
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r2`
[INFO] [stdout]    --> src/main.rs:204:9
[INFO] [stdout]     |
[INFO] [stdout] 204 |     let r2 = &mut s;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_r2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `feet`
[INFO] [stdout]     --> src/main.rs:1070:11
[INFO] [stdout]      |
[INFO] [stdout] 1070 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]      |           ^^^^ help: if this is intentional, prefix it with an underscore: `_feet`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r1`
[INFO] [stdout]    --> src/main.rs:208:9
[INFO] [stdout]     |
[INFO] [stdout] 208 |     let r1 = &s; // no problem
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_r1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `inches`
[INFO] [stdout]     --> src/main.rs:1070:17
[INFO] [stdout]      |
[INFO] [stdout] 1070 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]      |                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_inches`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r2`
[INFO] [stdout]    --> src/main.rs:209:9
[INFO] [stdout]     |
[INFO] [stdout] 209 |     let r2 = &s; // no problem
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_r2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]     --> src/main.rs:1070:34
[INFO] [stdout]      |
[INFO] [stdout] 1070 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]      |                                  ^ help: try ignoring the field: `x: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `slice`
[INFO] [stdout]    --> src/main.rs:233:9
[INFO] [stdout]     |
[INFO] [stdout] 233 |     let slice = &s[..];
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_slice`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]    --> src/main.rs:240:9
[INFO] [stdout]     |
[INFO] [stdout] 240 |     let word = first_word(&s);
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]     --> src/main.rs:1070:37
[INFO] [stdout]      |
[INFO] [stdout] 1070 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]      |                                     ^ help: try ignoring the field: `y: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r`
[INFO] [stdout]     --> src/main.rs:1159:9
[INFO] [stdout]      |
[INFO] [stdout] 1159 |     let r = address as *const i32;
[INFO] [stdout]      |         ^ help: if this is intentional, prefix it with an underscore: `_r`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `black`
[INFO] [stdout]    --> src/main.rs:271:9
[INFO] [stdout]     |
[INFO] [stdout] 271 |     let black = Color(0, 0, 0);
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_black`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `list_of_statuses`
[INFO] [stdout]     --> src/main.rs:1275:9
[INFO] [stdout]      |
[INFO] [stdout] 1275 |     let list_of_statuses: Vec<Status> = (0u32..20).map(Status::Value).collect();
[INFO] [stdout]      |         ^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_list_of_statuses`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `subject`
[INFO] [stdout]    --> src/main.rs:272:9
[INFO] [stdout]     |
[INFO] [stdout] 272 |     let subject = AlwaysEqual;
[INFO] [stdout]     |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_subject`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_number`
[INFO] [stdout]    --> src/main.rs:315:9
[INFO] [stdout]     |
[INFO] [stdout] 315 |     let some_number = Some(5);
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_char`
[INFO] [stdout]    --> src/main.rs:316:9
[INFO] [stdout]     |
[INFO] [stdout] 316 |     let some_char = Some('e');
[INFO] [stdout]     |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_char`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `absent_number`
[INFO] [stdout]    --> src/main.rs:317:9
[INFO] [stdout]     |
[INFO] [stdout] 317 |     let absent_number: Option<i32> = None;
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_absent_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:369:9
[INFO] [stdout]     |
[INFO] [stdout] 369 |     let v: Vec<i32> = Vec::new();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:370:9
[INFO] [stdout]     |
[INFO] [stdout] 370 |     let v = vec![1, 2, 3];
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `row`
[INFO] [stdout]    --> src/main.rs:410:9
[INFO] [stdout]     |
[INFO] [stdout] 410 |     let row = vec![
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_row`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:421:9
[INFO] [stdout]     |
[INFO] [stdout] 421 |     let mut s = String::new();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:425:9
[INFO] [stdout]     |
[INFO] [stdout] 425 |     let s = data.to_string();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:428:9
[INFO] [stdout]     |
[INFO] [stdout] 428 |     let s = "initial contents".to_string();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:430:9
[INFO] [stdout]     |
[INFO] [stdout] 430 |     let s = String::from("initial contents");
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:433:9
[INFO] [stdout]     |
[INFO] [stdout] 433 |     let hello = String::from("السلام عليكم");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:434:9
[INFO] [stdout]     |
[INFO] [stdout] 434 |     let hello = String::from("Dobrý den");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:435:9
[INFO] [stdout]     |
[INFO] [stdout] 435 |     let hello = String::from("Hello");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:436:9
[INFO] [stdout]     |
[INFO] [stdout] 436 |     let hello = String::from("שָׁלוֹם");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:437:9
[INFO] [stdout]     |
[INFO] [stdout] 437 |     let hello = String::from("नमस्ते");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:438:9
[INFO] [stdout]     |
[INFO] [stdout] 438 |     let hello = String::from("こんにちは");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:439:9
[INFO] [stdout]     |
[INFO] [stdout] 439 |     let hello = String::from("안녕하세요");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:440:9
[INFO] [stdout]     |
[INFO] [stdout] 440 |     let hello = String::from("你好");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:441:9
[INFO] [stdout]     |
[INFO] [stdout] 441 |     let hello = String::from("Olá");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `hello`
[INFO] [stdout]    --> src/main.rs:442:9
[INFO] [stdout]     |
[INFO] [stdout] 442 |     let hello = String::from("Hola");
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_hello`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:451:9
[INFO] [stdout]     |
[INFO] [stdout] 451 |     let s = &hello[0..4];
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> src/main.rs:481:9
[INFO] [stdout]     |
[INFO] [stdout] 481 |     let s3 = s1 + &s2; // note s1 has been moved here and can no longer be used
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:487:9
[INFO] [stdout]     |
[INFO] [stdout] 487 |     let s = format!("{s1}-{s2}-{s3}");
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> src/main.rs:522:9
[INFO] [stdout]     |
[INFO] [stdout] 522 |     let x = scores
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:526:9
[INFO] [stdout]     |
[INFO] [stdout] 526 |     let y = scores
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `greeting_file`
[INFO] [stdout]    --> src/main.rs:554:9
[INFO] [stdout]     |
[INFO] [stdout] 554 |     let greeting_file = match File::open("hello.txt") {
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_greeting_file`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `greeting_file`
[INFO] [stdout]    --> src/main.rs:568:9
[INFO] [stdout]     |
[INFO] [stdout] 568 |     let greeting_file = File::open("hello.txt").unwrap_or_else(|error| {
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_greeting_file`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `greeting_file`
[INFO] [stdout]    --> src/main.rs:586:9
[INFO] [stdout]     |
[INFO] [stdout] 586 |     let greeting_file = std::fs::read_to_string("hello.txt")?;
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_greeting_file`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]    --> src/main.rs:588:9
[INFO] [stdout]     |
[INFO] [stdout] 588 |     let home: std::net::IpAddr = "127.0.0.1"
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/main.rs:641:9
[INFO] [stdout]     |
[INFO] [stdout] 641 |     let i = ImportantExcerpt {
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:651:9
[INFO] [stdout]     |
[INFO] [stdout] 651 |     let s: &'static str = "I have a static lifetime.";
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `expensive_closure`
[INFO] [stdout]    --> src/main.rs:671:9
[INFO] [stdout]     |
[INFO] [stdout] 671 |     let expensive_closure = |num: u32| -> u32 {
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_expensive_closure`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `add_one_v2`
[INFO] [stdout]    --> src/main.rs:680:9
[INFO] [stdout]     |
[INFO] [stdout] 680 |     let add_one_v2 = |x: u32| -> u32 { x + 1 };
[INFO] [stdout]     |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_add_one_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> src/main.rs:821:9
[INFO] [stdout]     |
[INFO] [stdout] 821 |     let b = Cons(Rc::new(RefCell::new(3)), Rc::clone(&a));
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> src/main.rs:822:9
[INFO] [stdout]     |
[INFO] [stdout] 822 |     let c = Cons(Rc::new(RefCell::new(4)), Rc::clone(&a));
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> src/main.rs:827:9
[INFO] [stdout]     |
[INFO] [stdout] 827 |     let b = Cons(Rc::new(RefCell::new(3)), Rc::clone(&a));
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> src/main.rs:831:13
[INFO] [stdout]     |
[INFO] [stdout] 831 |         let c = Cons(Rc::new(RefCell::new(4)), Rc::clone(&a));
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `feet`
[INFO] [stdout]     --> src/main.rs:1070:11
[INFO] [stdout]      |
[INFO] [stdout] 1070 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]      |           ^^^^ help: if this is intentional, prefix it with an underscore: `_feet`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `inches`
[INFO] [stdout]     --> src/main.rs:1070:17
[INFO] [stdout]      |
[INFO] [stdout] 1070 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]      |                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_inches`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]     --> src/main.rs:1070:34
[INFO] [stdout]      |
[INFO] [stdout] 1070 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]      |                                  ^ help: try ignoring the field: `x: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]     --> src/main.rs:1070:37
[INFO] [stdout]      |
[INFO] [stdout] 1070 |     let ((feet, inches), Point { x, y }) = ((3, 10), Point { x: 3, y: -10 });
[INFO] [stdout]      |                                     ^ help: try ignoring the field: `y: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r`
[INFO] [stdout]     --> src/main.rs:1159:9
[INFO] [stdout]      |
[INFO] [stdout] 1159 |     let r = address as *const i32;
[INFO] [stdout]      |         ^ help: if this is intentional, prefix it with an underscore: `_r`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `list_of_statuses`
[INFO] [stdout]     --> src/main.rs:1275:9
[INFO] [stdout]      |
[INFO] [stdout] 1275 |     let list_of_statuses: Vec<Status> = (0u32..20).map(Status::Value).collect();
[INFO] [stdout]      |         ^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_list_of_statuses`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]     --> src/main.rs:1287:11
[INFO] [stdout]      |
[INFO] [stdout] 1287 |     Value(u32),
[INFO] [stdout]      |     ----- ^^^
[INFO] [stdout]      |     |
[INFO] [stdout]      |     field in this variant
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) 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] 1287 -     Value(u32),
[INFO] [stdout] 1287 +     Value(()),
[INFO] [stdout]      |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Stop` is never constructed
[INFO] [stdout]     --> src/main.rs:1288:5
[INFO] [stdout]      |
[INFO] [stdout] 1286 | enum Status {
[INFO] [stdout]      |      ------ variant in this enum
[INFO] [stdout] 1287 |     Value(u32),
[INFO] [stdout] 1288 |     Stop,
[INFO] [stdout]      |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Foo` is never used
[INFO] [stdout]     --> src/main.rs:1354:14
[INFO] [stdout]      |
[INFO] [stdout] 1354 | unsafe trait Foo {
[INFO] [stdout]      |              ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `width`, `height`, and `options` are never read
[INFO] [stdout]     --> src/main.rs:1431:5
[INFO] [stdout]      |
[INFO] [stdout] 1430 | struct SelectBox {
[INFO] [stdout]      |        --------- fields in this struct
[INFO] [stdout] 1431 |     width: u32,
[INFO] [stdout]      |     ^^^^^
[INFO] [stdout] 1432 |     height: u32,
[INFO] [stdout]      |     ^^^^^^
[INFO] [stdout] 1433 |     options: Vec<String>,
[INFO] [stdout]      |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]     --> src/main.rs:1469:10
[INFO] [stdout]      |
[INFO] [stdout] 1469 |     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] 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] 1469 -     Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout] 1469 +     Cons((), ()),
[INFO] [stdout]      |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `longest_with_an_announcement` is never used
[INFO] [stdout]     --> src/main.rs:1483:4
[INFO] [stdout]      |
[INFO] [stdout] 1483 | fn longest_with_an_announcement<'a, T>(
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `part` is never read
[INFO] [stdout]     --> src/main.rs:1500:5
[INFO] [stdout]      |
[INFO] [stdout] 1499 | struct ImportantExcerpt<'a> {
[INFO] [stdout]      |        ---------------- field in this struct
[INFO] [stdout] 1500 |     part: &'a str,
[INFO] [stdout]      |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `level` and `announce_and_return_part` are never used
[INFO] [stdout]     --> src/main.rs:1503:8
[INFO] [stdout]      |
[INFO] [stdout] 1502 | impl<'a> ImportantExcerpt<'a> {
[INFO] [stdout]      | ----------------------------- methods in this implementation
[INFO] [stdout] 1503 |     fn level(&self) -> i32 {
[INFO] [stdout]      |        ^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 1511 |     fn announce_and_return_part(&self, announcement: &str) -> &str {
[INFO] [stdout]      |        ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Pair` is never constructed
[INFO] [stdout]     --> src/main.rs:1535:8
[INFO] [stdout]      |
[INFO] [stdout] 1535 | struct Pair<T> {
[INFO] [stdout]      |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]     --> src/main.rs:1541:8
[INFO] [stdout]      |
[INFO] [stdout] 1540 | impl<T> Pair<T> {
[INFO] [stdout]      | --------------- associated function in this implementation
[INFO] [stdout] 1541 |     fn new(x: T, y: T) -> Self {
[INFO] [stdout]      |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `cmp_display` is never used
[INFO] [stdout]     --> src/main.rs:1547:8
[INFO] [stdout]      |
[INFO] [stdout] 1546 | impl<T: Display + PartialOrd> Pair<T> {
[INFO] [stdout]      | ------------------------------------- method in this implementation
[INFO] [stdout] 1547 |     fn cmp_display(&self) {
[INFO] [stdout]      |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `returns_summarizable` is never used
[INFO] [stdout]     --> src/main.rs:1573:4
[INFO] [stdout]      |
[INFO] [stdout] 1573 | fn returns_summarizable() -> impl Summary {
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `last_char_of_first_line` is never used
[INFO] [stdout]     --> src/main.rs:1685:4
[INFO] [stdout]      |
[INFO] [stdout] 1685 | fn last_char_of_first_line(text: &str) -> Option<char> {
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_username_from_file` is never used
[INFO] [stdout]     --> src/main.rs:1691:4
[INFO] [stdout]      |
[INFO] [stdout] 1691 | fn read_username_from_file() -> Result<String, io::Error> {
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Alabama` and `Alaska` are never constructed
[INFO] [stdout]     --> src/main.rs:1712:5
[INFO] [stdout]      |
[INFO] [stdout] 1711 | enum UsState {
[INFO] [stdout]      |      ------- variants in this enum
[INFO] [stdout] 1712 |     Alabama,
[INFO] [stdout]      |     ^^^^^^^
[INFO] [stdout] 1713 |     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] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Quit` and `Move` are never constructed
[INFO] [stdout]     --> src/main.rs:1741:5
[INFO] [stdout]      |
[INFO] [stdout] 1740 | enum Message {
[INFO] [stdout]      |      ------- variants in this enum
[INFO] [stdout] 1741 |     Quit,
[INFO] [stdout]      |     ^^^^
[INFO] [stdout] 1742 |     Move { x: i32, y: i32 },
[INFO] [stdout]      |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `active`, `username`, and `sign_in_count` are never read
[INFO] [stdout]     --> src/main.rs:1770:5
[INFO] [stdout]      |
[INFO] [stdout] 1769 | struct User {
[INFO] [stdout]      |        ---- fields in this struct
[INFO] [stdout] 1770 |     active: bool,
[INFO] [stdout]      |     ^^^^^^
[INFO] [stdout] 1771 |     username: String,
[INFO] [stdout]      |     ^^^^^^^^
[INFO] [stdout] 1772 |     email: String,
[INFO] [stdout] 1773 |     sign_in_count: u64,
[INFO] [stdout]      |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, and `2` are never read
[INFO] [stdout]     --> src/main.rs:1794:14
[INFO] [stdout]      |
[INFO] [stdout] 1794 | struct Color(i32, i32, i32);
[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 `first_word_book` is never used
[INFO] [stdout]     --> src/main.rs:1805:4
[INFO] [stdout]      |
[INFO] [stdout] 1805 | fn first_word_book(s: &String) -> &str {
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]    --> src/main.rs:404:13
[INFO] [stdout]     |
[INFO] [stdout] 404 |         Int(i32),
[INFO] [stdout]     |         --- ^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         field in this variant
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) 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] 404 -         Int(i32),
[INFO] [stdout] 404 +         Int(()),
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]    --> src/main.rs:405:15
[INFO] [stdout]     |
[INFO] [stdout] 405 |         Float(f64),
[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] 405 -         Float(f64),
[INFO] [stdout] 405 +         Float(()),
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]    --> src/main.rs:406:14
[INFO] [stdout]     |
[INFO] [stdout] 406 |         Text(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] 406 -         Text(String),
[INFO] [stdout] 406 +         Text(()),
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_v1` is never used
[INFO] [stdout]    --> src/main.rs:679:9
[INFO] [stdout]     |
[INFO] [stdout] 679 |     fn  add_one_v1(x: u32) -> u32 { x + 1 }
[INFO] [stdout]     |         ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]     --> src/main.rs:1287:11
[INFO] [stdout]      |
[INFO] [stdout] 1287 |     Value(u32),
[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] 1287 -     Value(u32),
[INFO] [stdout] 1287 +     Value(()),
[INFO] [stdout]      |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Stop` is never constructed
[INFO] [stdout]     --> src/main.rs:1288:5
[INFO] [stdout]      |
[INFO] [stdout] 1286 | enum Status {
[INFO] [stdout]      |      ------ variant in this enum
[INFO] [stdout] 1287 |     Value(u32),
[INFO] [stdout] 1288 |     Stop,
[INFO] [stdout]      |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Foo` is never used
[INFO] [stdout]     --> src/main.rs:1354:14
[INFO] [stdout]      |
[INFO] [stdout] 1354 | unsafe trait Foo {
[INFO] [stdout]      |              ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: creating a shared reference to mutable static
[INFO] [stdout]     --> src/main.rs:1230:33
[INFO] [stdout]      |
[INFO] [stdout] 1230 |         println!("COUNTER: {}", COUNTER);
[INFO] [stdout]      |                                 ^^^^^^^ shared reference to mutable static
[INFO] [stdout]      |
[INFO] [stdout]      = note: shared references to mutable statics are dangerous; it's undefined behavior if the static is mutated or if a mutable reference is created for it while the shared reference lives
[INFO] [stdout]      = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2024/static-mut-references.html>
[INFO] [stdout]      = note: `#[warn(static_mut_refs)]` (part of `#[warn(rust_2024_compatibility)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `width`, `height`, and `options` are never read
[INFO] [stdout]     --> src/main.rs:1431:5
[INFO] [stdout]      |
[INFO] [stdout] 1430 | struct SelectBox {
[INFO] [stdout]      |        --------- fields in this struct
[INFO] [stdout] 1431 |     width: u32,
[INFO] [stdout]      |     ^^^^^
[INFO] [stdout] 1432 |     height: u32,
[INFO] [stdout]      |     ^^^^^^
[INFO] [stdout] 1433 |     options: Vec<String>,
[INFO] [stdout]      |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]     --> src/main.rs:1469:10
[INFO] [stdout]      |
[INFO] [stdout] 1469 |     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] 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] 1469 -     Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout] 1469 +     Cons((), ()),
[INFO] [stdout]      |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `longest_with_an_announcement` is never used
[INFO] [stdout]     --> src/main.rs:1483:4
[INFO] [stdout]      |
[INFO] [stdout] 1483 | fn longest_with_an_announcement<'a, T>(
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `part` is never read
[INFO] [stdout]     --> src/main.rs:1500:5
[INFO] [stdout]      |
[INFO] [stdout] 1499 | struct ImportantExcerpt<'a> {
[INFO] [stdout]      |        ---------------- field in this struct
[INFO] [stdout] 1500 |     part: &'a str,
[INFO] [stdout]      |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `level` and `announce_and_return_part` are never used
[INFO] [stdout]     --> src/main.rs:1503:8
[INFO] [stdout]      |
[INFO] [stdout] 1502 | impl<'a> ImportantExcerpt<'a> {
[INFO] [stdout]      | ----------------------------- methods in this implementation
[INFO] [stdout] 1503 |     fn level(&self) -> i32 {
[INFO] [stdout]      |        ^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 1511 |     fn announce_and_return_part(&self, announcement: &str) -> &str {
[INFO] [stdout]      |        ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Pair` is never constructed
[INFO] [stdout]     --> src/main.rs:1535:8
[INFO] [stdout]      |
[INFO] [stdout] 1535 | struct Pair<T> {
[INFO] [stdout]      |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]     --> src/main.rs:1541:8
[INFO] [stdout]      |
[INFO] [stdout] 1540 | impl<T> Pair<T> {
[INFO] [stdout]      | --------------- associated function in this implementation
[INFO] [stdout] 1541 |     fn new(x: T, y: T) -> Self {
[INFO] [stdout]      |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `cmp_display` is never used
[INFO] [stdout]     --> src/main.rs:1547:8
[INFO] [stdout]      |
[INFO] [stdout] 1546 | impl<T: Display + PartialOrd> Pair<T> {
[INFO] [stdout]      | ------------------------------------- method in this implementation
[INFO] [stdout] 1547 |     fn cmp_display(&self) {
[INFO] [stdout]      |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `returns_summarizable` is never used
[INFO] [stdout]     --> src/main.rs:1573:4
[INFO] [stdout]      |
[INFO] [stdout] 1573 | fn returns_summarizable() -> impl Summary {
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `last_char_of_first_line` is never used
[INFO] [stdout]     --> src/main.rs:1685:4
[INFO] [stdout]      |
[INFO] [stdout] 1685 | fn last_char_of_first_line(text: &str) -> Option<char> {
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_username_from_file` is never used
[INFO] [stdout]     --> src/main.rs:1691:4
[INFO] [stdout]      |
[INFO] [stdout] 1691 | fn read_username_from_file() -> Result<String, io::Error> {
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Alabama` and `Alaska` are never constructed
[INFO] [stdout]     --> src/main.rs:1712:5
[INFO] [stdout]      |
[INFO] [stdout] 1711 | enum UsState {
[INFO] [stdout]      |      ------- variants in this enum
[INFO] [stdout] 1712 |     Alabama,
[INFO] [stdout]      |     ^^^^^^^
[INFO] [stdout] 1713 |     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] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Quit` and `Move` are never constructed
[INFO] [stdout]     --> src/main.rs:1741:5
[INFO] [stdout]      |
[INFO] [stdout] 1740 | enum Message {
[INFO] [stdout]      |      ------- variants in this enum
[INFO] [stdout] 1741 |     Quit,
[INFO] [stdout]      |     ^^^^
[INFO] [stdout] 1742 |     Move { x: i32, y: i32 },
[INFO] [stdout]      |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `active`, `username`, and `sign_in_count` are never read
[INFO] [stdout]     --> src/main.rs:1770:5
[INFO] [stdout]      |
[INFO] [stdout] 1769 | struct User {
[INFO] [stdout]      |        ---- fields in this struct
[INFO] [stdout] 1770 |     active: bool,
[INFO] [stdout]      |     ^^^^^^
[INFO] [stdout] 1771 |     username: String,
[INFO] [stdout]      |     ^^^^^^^^
[INFO] [stdout] 1772 |     email: String,
[INFO] [stdout] 1773 |     sign_in_count: u64,
[INFO] [stdout]      |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, and `2` are never read
[INFO] [stdout]     --> src/main.rs:1794:14
[INFO] [stdout]      |
[INFO] [stdout] 1794 | struct Color(i32, i32, i32);
[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 `first_word_book` is never used
[INFO] [stdout]     --> src/main.rs:1805:4
[INFO] [stdout]      |
[INFO] [stdout] 1805 | fn first_word_book(s: &String) -> &str {
[INFO] [stdout]      |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: creating a shared reference to mutable static
[INFO] [stdout]     --> src/main.rs:1230:33
[INFO] [stdout]      |
[INFO] [stdout] 1230 |         println!("COUNTER: {}", COUNTER);
[INFO] [stdout]      |                                 ^^^^^^^ shared reference to mutable static
[INFO] [stdout]      |
[INFO] [stdout]      = note: shared references to mutable statics are dangerous; it's undefined behavior if the static is mutated or if a mutable reference is created for it while the shared reference lives
[INFO] [stdout]      = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2024/static-mut-references.html>
[INFO] [stdout]      = note: `#[warn(static_mut_refs)]` (part of `#[warn(rust_2024_compatibility)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.96s
[INFO] running `Command { std: "docker" "inspect" "9e13b9b5c7d1215ab3111656fd08cd04d73e5431c79bb639c371a1279ecb9885", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9e13b9b5c7d1215ab3111656fd08cd04d73e5431c79bb639c371a1279ecb9885", kill_on_drop: false }`
[INFO] [stdout] 9e13b9b5c7d1215ab3111656fd08cd04d73e5431c79bb639c371a1279ecb9885
