[INFO] cloning repository https://github.com/shgmjshn/rust-tutorial
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/shgmjshn/rust-tutorial" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshgmjshn%2Frust-tutorial", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshgmjshn%2Frust-tutorial'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a65275a1be118c9a8991493b86dfb79913d5d450
[INFO] checking shgmjshn/rust-tutorial against master#8c32e313cccf7df531e2d49ffb8227bb92304aee for pr-145608-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshgmjshn%2Frust-tutorial" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/shgmjshn/rust-tutorial
[INFO] finished tweaking git repo https://github.com/shgmjshn/rust-tutorial
[INFO] tweaked toml for git repo https://github.com/shgmjshn/rust-tutorial written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/shgmjshn/rust-tutorial on toolchain 8c32e313cccf7df531e2d49ffb8227bb92304aee
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+8c32e313cccf7df531e2d49ffb8227bb92304aee" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/shgmjshn/rust-tutorial 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" "+8c32e313cccf7df531e2d49ffb8227bb92304aee" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded futures-executor v0.3.31
[INFO] [stderr]   Downloaded futures-macro v0.3.31
[INFO] [stderr]   Downloaded quote v1.0.39
[INFO] [stderr]   Downloaded futures v0.3.31
[INFO] [stderr]   Downloaded syn v2.0.99
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+8c32e313cccf7df531e2d49ffb8227bb92304aee" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 52000d214fc74dec73d1e1646fc46d7dc17790b0aed26151d1c003d3029e178b
[INFO] running `Command { std: "docker" "start" "-a" "52000d214fc74dec73d1e1646fc46d7dc17790b0aed26151d1c003d3029e178b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "52000d214fc74dec73d1e1646fc46d7dc17790b0aed26151d1c003d3029e178b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "52000d214fc74dec73d1e1646fc46d7dc17790b0aed26151d1c003d3029e178b", kill_on_drop: false }`
[INFO] [stdout] 52000d214fc74dec73d1e1646fc46d7dc17790b0aed26151d1c003d3029e178b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+8c32e313cccf7df531e2d49ffb8227bb92304aee" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 811b3d7017c9a3335ecabaad9d82724f76fa5a765ae1346f214d7d6867e66c79
[INFO] running `Command { std: "docker" "start" "-a" "811b3d7017c9a3335ecabaad9d82724f76fa5a765ae1346f214d7d6867e66c79", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.94
[INFO] [stderr]    Compiling unicode-ident v1.0.18
[INFO] [stderr]    Compiling autocfg v1.4.0
[INFO] [stderr]     Checking futures-sink v0.3.31
[INFO] [stderr]     Checking futures-core v0.3.31
[INFO] [stderr]     Checking futures-task v0.3.31
[INFO] [stderr]     Checking pin-utils v0.1.0
[INFO] [stderr]     Checking futures-io v0.3.31
[INFO] [stderr]     Checking pin-project-lite v0.2.16
[INFO] [stderr]     Checking memchr v2.7.4
[INFO] [stderr]     Checking futures-channel v0.3.31
[INFO] [stderr]    Compiling slab v0.4.9
[INFO] [stderr]    Compiling quote v1.0.39
[INFO] [stderr]    Compiling syn v2.0.99
[INFO] [stderr]    Compiling futures-macro v0.3.31
[INFO] [stderr]     Checking futures-util v0.3.31
[INFO] [stderr]     Checking futures-executor v0.3.31
[INFO] [stderr]     Checking futures v0.3.31
[INFO] [stderr]     Checking hello v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused label
[INFO] [stdout]    --> src/main.rs:369:9
[INFO] [stdout]     |
[INFO] [stdout] 369 |         'sub: loop {
[INFO] [stdout]     |         ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_labels)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused label
[INFO] [stdout]    --> src/main.rs:369:9
[INFO] [stdout]     |
[INFO] [stdout] 369 |         'sub: loop {
[INFO] [stdout]     |         ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_labels)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `user_id`
[INFO] [stdout]    --> src/main.rs:112:37
[INFO] [stdout]     |
[INFO] [stdout] 112 |     async fn find_by_user_id(&self, user_id: UserId) -> Option<User> {
[INFO] [stdout]     |                                     ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_user_id`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `user_id`
[INFO] [stdout]    --> src/main.rs:112:37
[INFO] [stdout]     |
[INFO] [stdout] 112 |     async fn find_by_user_id(&self, user_id: UserId) -> Option<User> {
[INFO] [stdout]     |                                     ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_user_id`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]    --> src/main.rs:374:13
[INFO] [stdout]     |
[INFO] [stdout] 372 |             break 'main;
[INFO] [stdout]     |             ----------- any code following this expression is unreachable
[INFO] [stdout] 373 |
[INFO] [stdout] 374 |             println!("sub loop end"); //表示されない
[INFO] [stdout]     |             ^^^^^^^^^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout]     = note: this warning originates in the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]    --> src/main.rs:374:13
[INFO] [stdout]     |
[INFO] [stdout] 372 |             break 'main;
[INFO] [stdout]     |             ----------- any code following this expression is unreachable
[INFO] [stdout] 373 |
[INFO] [stdout] 374 |             println!("sub loop end"); //表示されない
[INFO] [stdout]     |             ^^^^^^^^^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout]     = note: this warning originates in the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]    --> src/main.rs:453:5
[INFO] [stdout]     |
[INFO] [stdout] 450 |     panic!("it will be panic");
[INFO] [stdout]     |     -------------------------- any code following this expression is unreachable
[INFO] [stdout] ...
[INFO] [stdout] 453 |     let v = vec![1, 2, 3];
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]    --> src/main.rs:453:5
[INFO] [stdout]     |
[INFO] [stdout] 450 |     panic!("it will be panic");
[INFO] [stdout]     |     -------------------------- any code following this expression is unreachable
[INFO] [stdout] ...
[INFO] [stdout] 453 |     let v = vec![1, 2, 3];
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e1`
[INFO] [stdout]    --> src/main.rs:261:9
[INFO] [stdout]     |
[INFO] [stdout] 261 |     let e1 = Event::Quit;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_e1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e1`
[INFO] [stdout]    --> src/main.rs:261:9
[INFO] [stdout]     |
[INFO] [stdout] 261 |     let e1 = Event::Quit;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_e1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e2`
[INFO] [stdout]    --> src/main.rs:262:9
[INFO] [stdout]     |
[INFO] [stdout] 262 |     let e2 = Event::MouseDown {x: 10, y: 20};
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_e2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e2`
[INFO] [stdout]    --> src/main.rs:262:9
[INFO] [stdout]     |
[INFO] [stdout] 262 |     let e2 = Event::MouseDown {x: 10, y: 20};
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_e2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next_result`
[INFO] [stdout]    --> src/main.rs:289:9
[INFO] [stdout]     |
[INFO] [stdout] 289 |     let next_result = result.and_then(func); //func()は実行される
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_next_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next_result`
[INFO] [stdout]    --> src/main.rs:289:9
[INFO] [stdout]     |
[INFO] [stdout] 289 |     let next_result = result.and_then(func); //func()は実行される
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_next_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next_result`
[INFO] [stdout]    --> src/main.rs:291:9
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let next_result = result.and_then(func); //func()は実行されない
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_next_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `next_result`
[INFO] [stdout]    --> src/main.rs:291:9
[INFO] [stdout]     |
[INFO] [stdout] 291 |     let next_result = result.and_then(func); //func()は実行されない
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_next_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v1`
[INFO] [stdout]    --> src/main.rs:299:9
[INFO] [stdout]     |
[INFO] [stdout] 299 |     let v1 = vec![1, 2, 3, 4, 5]; //1～5の数字を入れて初期化
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v1`
[INFO] [stdout]    --> src/main.rs:299:9
[INFO] [stdout]     |
[INFO] [stdout] 299 |     let v1 = vec![1, 2, 3, 4, 5]; //1～5の数字を入れて初期化
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v2`
[INFO] [stdout]    --> src/main.rs:300:9
[INFO] [stdout]     |
[INFO] [stdout] 300 |     let v2 = vec![0; 5]; //0を5つ入れて初期化
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `mut_val` is assigned to, but never used
[INFO] [stdout]    --> src/main.rs:316:13
[INFO] [stdout]     |
[INFO] [stdout] 316 |     let mut mut_val = 20;
[INFO] [stdout]     |             ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_mut_val` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v2`
[INFO] [stdout]    --> src/main.rs:300:9
[INFO] [stdout]     |
[INFO] [stdout] 300 |     let v2 = vec![0; 5]; //0を5つ入れて初期化
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `mut_val` is assigned to, but never used
[INFO] [stdout]    --> src/main.rs:316:13
[INFO] [stdout]     |
[INFO] [stdout] 316 |     let mut mut_val = 20;
[INFO] [stdout]     |             ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_mut_val` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `mut_val` is never read
[INFO] [stdout]    --> src/main.rs:318:5
[INFO] [stdout]     |
[INFO] [stdout] 318 |     mut_val += immut_val;
[INFO] [stdout]     |     ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `mut_val` is never read
[INFO] [stdout]    --> src/main.rs:318:5
[INFO] [stdout]     |
[INFO] [stdout] 318 |     mut_val += immut_val;
[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: unused variable: `v1`
[INFO] [stdout]    --> src/main.rs:320:9
[INFO] [stdout]     |
[INFO] [stdout] 320 |     let v1: u64 = 10;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v2`
[INFO] [stdout]    --> src/main.rs:321:9
[INFO] [stdout]     |
[INFO] [stdout] 321 |     let v2 = 10u64;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v1`
[INFO] [stdout]    --> src/main.rs:320:9
[INFO] [stdout]     |
[INFO] [stdout] 320 |     let v1: u64 = 10;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `result`
[INFO] [stdout]    --> src/main.rs:333:9
[INFO] [stdout]     |
[INFO] [stdout] 333 |     let result = if 0 <= number {
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v2`
[INFO] [stdout]    --> src/main.rs:321:9
[INFO] [stdout]     |
[INFO] [stdout] 321 |     let v2 = 10u64;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `result`
[INFO] [stdout]    --> src/main.rs:341:9
[INFO] [stdout]     |
[INFO] [stdout] 341 |     let result = loop {
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `result`
[INFO] [stdout]    --> src/main.rs:333:9
[INFO] [stdout]     |
[INFO] [stdout] 333 |     let result = if 0 <= number {
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `count`
[INFO] [stdout]    --> src/main.rs:355:9
[INFO] [stdout]     |
[INFO] [stdout] 355 |     let count: i32;
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_count`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `result`
[INFO] [stdout]    --> src/main.rs:341:9
[INFO] [stdout]     |
[INFO] [stdout] 341 |     let result = loop {
[INFO] [stdout]     |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `result_number`
[INFO] [stdout]    --> src/main.rs:401:9
[INFO] [stdout]     |
[INFO] [stdout] 401 |     let result_number = match result {
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_result_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `count`
[INFO] [stdout]    --> src/main.rs:355:9
[INFO] [stdout]     |
[INFO] [stdout] 355 |     let count: i32;
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_count`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:436:9
[INFO] [stdout]     |
[INFO] [stdout] 436 |     let s = format!("{}-{:?}", "Ab2", ("D", 5)); //s = String::form("Ab23(\"D\", 5)")と同じ
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `result_number`
[INFO] [stdout]    --> src/main.rs:401:9
[INFO] [stdout]     |
[INFO] [stdout] 401 |     let result_number = match result {
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_result_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:437:9
[INFO] [stdout]     |
[INFO] [stdout] 437 |     let s = format!("{}{}", "abc", "def"); //s = String::from("abcdef")と同じ
[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:436:9
[INFO] [stdout]     |
[INFO] [stdout] 436 |     let s = format!("{}-{:?}", "Ab2", ("D", 5)); //s = String::form("Ab23(\"D\", 5)")と同じ
[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:438:9
[INFO] [stdout]     |
[INFO] [stdout] 438 |     let s = concat!("A", "b2", 3); //s = String::from("Ab23")と同じ
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:453:9
[INFO] [stdout]     |
[INFO] [stdout] 453 |     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: `s`
[INFO] [stdout]    --> src/main.rs:437:9
[INFO] [stdout]     |
[INFO] [stdout] 437 |     let s = format!("{}{}", "abc", "def"); //s = String::from("abcdef")と同じ
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t1`
[INFO] [stdout]    --> src/main.rs:506:9
[INFO] [stdout]     |
[INFO] [stdout] 506 |     let t1 = make_tuple(1, 2);
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]    --> src/main.rs:438:9
[INFO] [stdout]     |
[INFO] [stdout] 438 |     let s = concat!("A", "b2", 3); //s = String::from("Ab23")と同じ
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:453:9
[INFO] [stdout]     |
[INFO] [stdout] 453 |     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: `t2`
[INFO] [stdout]    --> src/main.rs:507:9
[INFO] [stdout]     |
[INFO] [stdout] 507 |     let t2 = make_tuple("Hello", "World!");
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t3`
[INFO] [stdout]    --> src/main.rs:508:9
[INFO] [stdout]     |
[INFO] [stdout] 508 |     let t3 = make_tuple(vec![1, 2, 3], vec![4, 5]);
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t1`
[INFO] [stdout]    --> src/main.rs:506:9
[INFO] [stdout]     |
[INFO] [stdout] 506 |     let t1 = make_tuple(1, 2);
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t2`
[INFO] [stdout]    --> src/main.rs:507:9
[INFO] [stdout]     |
[INFO] [stdout] 507 |     let t2 = make_tuple("Hello", "World!");
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t4`
[INFO] [stdout]    --> src/main.rs:509:9
[INFO] [stdout]     |
[INFO] [stdout] 509 |     let t4 = make_tuple(3, "years old");
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t4`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t3`
[INFO] [stdout]    --> src/main.rs:508:9
[INFO] [stdout]     |
[INFO] [stdout] 508 |     let t3 = make_tuple(vec![1, 2, 3], vec![4, 5]);
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `d`
[INFO] [stdout]    --> src/main.rs:552:13
[INFO] [stdout]     |
[INFO] [stdout] 552 |         let d = Droppable;
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t4`
[INFO] [stdout]    --> src/main.rs:509:9
[INFO] [stdout]     |
[INFO] [stdout] 509 |     let t4 = make_tuple(3, "years old");
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_t4`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `d`
[INFO] [stdout]    --> src/main.rs:552:13
[INFO] [stdout]     |
[INFO] [stdout] 552 |         let d = Droppable;
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_great_function` is never used
[INFO] [stdout]   --> src/main.rs:13:10
[INFO] [stdout]    |
[INFO] [stdout] 13 | async fn some_great_function(arg: &i32) -> i32 {
[INFO] [stdout]    |          ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_great_function_expanded` is never used
[INFO] [stdout]   --> src/main.rs:19:4
[INFO] [stdout]    |
[INFO] [stdout] 19 | fn some_great_function_expanded<'a>(arg: &'a i32) -> impl Future<Output = i32> + 'a {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_great_function_example` is never used
[INFO] [stdout]   --> src/main.rs:26:4
[INFO] [stdout]    |
[INFO] [stdout] 26 | fn some_great_function_example() -> impl Future<Output = i32> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `send_to_another_thread_with_borrowing` is never used
[INFO] [stdout]   --> src/main.rs:35:10
[INFO] [stdout]    |
[INFO] [stdout] 35 | async fn send_to_another_thread_with_borrowing(x: &i32) -> i32 {
[INFO] [stdout]    |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_great_function_correct` is never used
[INFO] [stdout]   --> src/main.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn some_great_function_correct() -> impl Future<Output = i32> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `move_to_async_block` is never used
[INFO] [stdout]   --> src/main.rs:47:4
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn move_to_async_block() -> impl Future<Output = ()> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `print_async` is never used
[INFO] [stdout]   --> src/main.rs:57:10
[INFO] [stdout]    |
[INFO] [stdout] 57 | async fn print_async(value: i32) {
[INFO] [stdout]    |          ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `calculate` is never used
[INFO] [stdout]   --> src/main.rs:61:10
[INFO] [stdout]    |
[INFO] [stdout] 61 | async fn calculate() -> i32 {
[INFO] [stdout]    |          ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]    --> src/main.rs:107:15
[INFO] [stdout]     |
[INFO] [stdout] 107 | struct UserId(u32);
[INFO] [stdout]     |        ------ ^^^
[INFO] [stdout]     |        |
[INFO] [stdout]     |        field in this struct
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider removing this field
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Penguin` is never constructed
[INFO] [stdout]    --> src/main.rs:161:8
[INFO] [stdout]     |
[INFO] [stdout] 161 | struct Penguin {
[INFO] [stdout]     |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `f` is never used
[INFO] [stdout]    --> src/main.rs:186:4
[INFO] [stdout]     |
[INFO] [stdout] 186 | fn f(x: i32) -> &'static str {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_great_function` is never used
[INFO] [stdout]   --> src/main.rs:13:10
[INFO] [stdout]    |
[INFO] [stdout] 13 | async fn some_great_function(arg: &i32) -> i32 {
[INFO] [stdout]    |          ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Anger` is never constructed
[INFO] [stdout]    --> src/main.rs:199:5
[INFO] [stdout]     |
[INFO] [stdout] 198 | enum Emotion {
[INFO] [stdout]     |      ------- variant in this enum
[INFO] [stdout] 199 |     Anger,
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_great_function_expanded` is never used
[INFO] [stdout]   --> src/main.rs:19:4
[INFO] [stdout]    |
[INFO] [stdout] 19 | fn some_great_function_expanded<'a>(arg: &'a i32) -> impl Future<Output = i32> + 'a {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_great_function_example` is never used
[INFO] [stdout]   --> src/main.rs:26:4
[INFO] [stdout]    |
[INFO] [stdout] 26 | fn some_great_function_example() -> impl Future<Output = i32> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `get_anger` and `tell_state` are never used
[INFO] [stdout]    --> src/main.rs:205:8
[INFO] [stdout]     |
[INFO] [stdout] 203 | trait Emotional {
[INFO] [stdout]     |       --------- methods in this trait
[INFO] [stdout] 204 |     fn get_happy(&mut self) -> String;
[INFO] [stdout] 205 |     fn get_anger(&mut self) -> String;
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 206 |     fn tell_state(&self) -> String;
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `send_to_another_thread_with_borrowing` is never used
[INFO] [stdout]   --> src/main.rs:35:10
[INFO] [stdout]    |
[INFO] [stdout] 35 | async fn send_to_another_thread_with_borrowing(x: &i32) -> i32 {
[INFO] [stdout]    |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_great_function_correct` is never used
[INFO] [stdout]   --> src/main.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn some_great_function_correct() -> impl Future<Output = i32> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `state` is never read
[INFO] [stdout]    --> src/main.rs:211:5
[INFO] [stdout]     |
[INFO] [stdout] 209 | struct HappyPerson {
[INFO] [stdout]     |        ----------- field in this struct
[INFO] [stdout] 210 |     name: String,
[INFO] [stdout] 211 |     state: Emotion,
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Option` is never used
[INFO] [stdout]    --> src/main.rs:245:14
[INFO] [stdout]     |
[INFO] [stdout] 245 |     pub enum Option<T> {
[INFO] [stdout]     |              ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `move_to_async_block` is never used
[INFO] [stdout]   --> src/main.rs:47:4
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn move_to_async_block() -> impl Future<Output = ()> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `print_async` is never used
[INFO] [stdout]   --> src/main.rs:57:10
[INFO] [stdout]    |
[INFO] [stdout] 57 | async fn print_async(value: i32) {
[INFO] [stdout]    |          ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `x` and `y` are never read
[INFO] [stdout]    --> src/main.rs:258:21
[INFO] [stdout]     |
[INFO] [stdout] 258 |         MouseDown { x: i32, y: i32 },
[INFO] [stdout]     |         ---------   ^       ^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         fields in this variant
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `calculate` is never used
[INFO] [stdout]   --> src/main.rs:61:10
[INFO] [stdout]    |
[INFO] [stdout] 61 | async fn calculate() -> i32 {
[INFO] [stdout]    |          ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `KeyDown` is never constructed
[INFO] [stdout]    --> src/main.rs:257:9
[INFO] [stdout]     |
[INFO] [stdout] 255 |     enum Event {
[INFO] [stdout]     |          ----- variant in this enum
[INFO] [stdout] 256 |         Quit,
[INFO] [stdout] 257 |         KeyDown(u8),
[INFO] [stdout]     |         ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]    --> src/main.rs:107:15
[INFO] [stdout]     |
[INFO] [stdout] 107 | struct UserId(u32);
[INFO] [stdout]     |        ------ ^^^
[INFO] [stdout]     |        |
[INFO] [stdout]     |        field in this struct
[INFO] [stdout]     |
[INFO] [stdout]     = help: consider removing this field
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `error_handling` is never used
[INFO] [stdout]    --> src/main.rs:293:8
[INFO] [stdout]     |
[INFO] [stdout] 293 |     fn error_handling(result: Result<i32, String>) -> Result<i32, String> {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Penguin` is never constructed
[INFO] [stdout]    --> src/main.rs:161:8
[INFO] [stdout]     |
[INFO] [stdout] 161 | struct Penguin {
[INFO] [stdout]     |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `f` is never used
[INFO] [stdout]    --> src/main.rs:186:4
[INFO] [stdout]     |
[INFO] [stdout] 186 | fn f(x: i32) -> &'static str {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Anger` is never constructed
[INFO] [stdout]    --> src/main.rs:199:5
[INFO] [stdout]     |
[INFO] [stdout] 198 | enum Emotion {
[INFO] [stdout]     |      ------- variant in this enum
[INFO] [stdout] 199 |     Anger,
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Blue` and `Green` are never constructed
[INFO] [stdout]    --> src/main.rs:389:9
[INFO] [stdout]     |
[INFO] [stdout] 387 |     enum Color {
[INFO] [stdout]     |          ----- variants in this enum
[INFO] [stdout] 388 |         Red,
[INFO] [stdout] 389 |         Blue,
[INFO] [stdout]     |         ^^^^
[INFO] [stdout] 390 |         Green,
[INFO] [stdout]     |         ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `abs` is never used
[INFO] [stdout]    --> src/main.rs:675:4
[INFO] [stdout]     |
[INFO] [stdout] 675 | fn abs(number: i32) -> i32 {
[INFO] [stdout]     |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `get_anger` and `tell_state` are never used
[INFO] [stdout]    --> src/main.rs:205:8
[INFO] [stdout]     |
[INFO] [stdout] 203 | trait Emotional {
[INFO] [stdout]     |       --------- methods in this trait
[INFO] [stdout] 204 |     fn get_happy(&mut self) -> String;
[INFO] [stdout] 205 |     fn get_anger(&mut self) -> String;
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 206 |     fn tell_state(&self) -> String;
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `state` is never read
[INFO] [stdout]    --> src/main.rs:211:5
[INFO] [stdout]     |
[INFO] [stdout] 209 | struct HappyPerson {
[INFO] [stdout]     |        ----------- field in this struct
[INFO] [stdout] 210 |     name: String,
[INFO] [stdout] 211 |     state: Emotion,
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `abs` is never used
[INFO] [stdout]    --> src/main.rs:675:4
[INFO] [stdout]     |
[INFO] [stdout] 675 | fn abs(number: i32) -> i32 {
[INFO] [stdout]     |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused implementer of `futures::Future` that must be used
[INFO] [stdout]   --> src/main.rs:65:5
[INFO] [stdout]    |
[INFO] [stdout] 65 |     print_async(add1);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: futures do nothing unless you `.await` or poll them
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused implementer of `futures::Future` that must be used
[INFO] [stdout]   --> src/main.rs:65:5
[INFO] [stdout]    |
[INFO] [stdout] 65 |     print_async(add1);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: futures do nothing unless you `.await` or poll them
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused implementer of `futures::Future` that must be used
[INFO] [stdout]   --> src/main.rs:69:5
[INFO] [stdout]    |
[INFO] [stdout] 69 |     print_async(add2);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: futures do nothing unless you `.await` or poll them
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused implementer of `futures::Future` that must be used
[INFO] [stdout]   --> src/main.rs:69:5
[INFO] [stdout]    |
[INFO] [stdout] 69 |     print_async(add2);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: futures do nothing unless you `.await` or poll them
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:446:5
[INFO] [stdout]     |
[INFO] [stdout] 446 |     write!(&mut w, "{}", "ABC"); //UTF-8バイト列で65, 66, 67
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 446 |     let _ = write!(&mut w, "{}", "ABC"); //UTF-8バイト列で65, 66, 67
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:447:5
[INFO] [stdout]     |
[INFO] [stdout] 447 |     writeln!(&mut w, "is 123"); //UTF-8バイト列で32, 105, 115, 32, 49, 50, 51, 10
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 447 |     let _ = writeln!(&mut w, "is 123"); //UTF-8バイト列で32, 105, 115, 32, 49, 50, 51, 10
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:446:5
[INFO] [stdout]     |
[INFO] [stdout] 446 |     write!(&mut w, "{}", "ABC"); //UTF-8バイト列で65, 66, 67
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 446 |     let _ = write!(&mut w, "{}", "ABC"); //UTF-8バイト列で65, 66, 67
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:560:5
[INFO] [stdout]     |
[INFO] [stdout] 560 |     dbg!(handle.join());
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 560 |     let _ = dbg!(handle.join());
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:447:5
[INFO] [stdout]     |
[INFO] [stdout] 447 |     writeln!(&mut w, "is 123"); //UTF-8バイト列で32, 105, 115, 32, 49, 50, 51, 10
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 447 |     let _ = writeln!(&mut w, "is 123"); //UTF-8バイト列で32, 105, 115, 32, 49, 50, 51, 10
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:560:5
[INFO] [stdout]     |
[INFO] [stdout] 560 |     dbg!(handle.join());
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 560 |     let _ = dbg!(handle.join());
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.60s
[INFO] running `Command { std: "docker" "inspect" "811b3d7017c9a3335ecabaad9d82724f76fa5a765ae1346f214d7d6867e66c79", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "811b3d7017c9a3335ecabaad9d82724f76fa5a765ae1346f214d7d6867e66c79", kill_on_drop: false }`
[INFO] [stdout] 811b3d7017c9a3335ecabaad9d82724f76fa5a765ae1346f214d7d6867e66c79