[INFO] cloning repository https://github.com/Guang1234567/minigrep
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Guang1234567/minigrep" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FGuang1234567%2Fminigrep", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FGuang1234567%2Fminigrep'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ebf1c9da65374dbf50c51521d82a50ac9a8d16d8
[INFO] checking Guang1234567/minigrep against master#5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FGuang1234567%2Fminigrep" "/workspace/builds/worker-15/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-15/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Guang1234567/minigrep on toolchain 5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Guang1234567/minigrep
[INFO] finished tweaking git repo https://github.com/Guang1234567/minigrep
[INFO] tweaked toml for git repo https://github.com/Guang1234567/minigrep written to /workspace/builds/worker-15/source/Cargo.toml
[INFO] crate git repo https://github.com/Guang1234567/minigrep already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
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[INFO] [stdout] bcbebe633188a96beff1f10f84c07f8449493316a38af4517957601c12ad7a33
[INFO] running `Command { std: "docker" "start" "-a" "bcbebe633188a96beff1f10f84c07f8449493316a38af4517957601c12ad7a33", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bcbebe633188a96beff1f10f84c07f8449493316a38af4517957601c12ad7a33", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bcbebe633188a96beff1f10f84c07f8449493316a38af4517957601c12ad7a33", kill_on_drop: false }`
[INFO] [stdout] bcbebe633188a96beff1f10f84c07f8449493316a38af4517957601c12ad7a33
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a02618b8e3709d014ae269c9514ec19ca36c382c3bf58a62877900d535d4d13d
[INFO] running `Command { std: "docker" "start" "-a" "a02618b8e3709d014ae269c9514ec19ca36c382c3bf58a62877900d535d4d13d", kill_on_drop: false }`
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[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> src/thread_pool/mod.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::future::Future`
[INFO] [stdout]  --> src/thread_pool/mod.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::future::Future;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `self`
[INFO] [stdout]  --> src/print/mod.rs:2:15
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io::{self, Write};
[INFO] [stdout]   |               ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]  --> src/thread_demo/mod.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     use super::*;
[INFO] [stdout]   |         ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc`, `Mutex`
[INFO] [stdout]    --> src/oop_demo/mod.rs:119:21
[INFO] [stdout]     |
[INFO] [stdout] 119 |     use std::sync::{Arc, Mutex};
[INFO] [stdout]     |                     ^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::sync::mpsc`
[INFO] [stdout]    --> src/oop_demo/mod.rs:120:9
[INFO] [stdout]     |
[INFO] [stdout] 120 |     use std::sync::mpsc;
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread`
[INFO] [stdout]    --> src/oop_demo/mod.rs:121:9
[INFO] [stdout]     |
[INFO] [stdout] 121 |     use std::thread;
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::time::Duration`
[INFO] [stdout]    --> src/oop_demo/mod.rs:122:9
[INFO] [stdout]     |
[INFO] [stdout] 122 |     use std::time::Duration;
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> src/server_demo/mod.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Write`
[INFO] [stdout]  --> src/print/mod.rs:2:21
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io::{self, Write};
[INFO] [stdout]   |                     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]  --> src/oop_demo/mod.rs:9:27
[INFO] [stdout]   |
[INFO] [stdout] 9 |     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)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> src/thread_pool/mod.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::future::Future`
[INFO] [stdout]  --> src/thread_pool/mod.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::future::Future;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Cacher`
[INFO] [stdout]  --> src/cache/mod.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Cacher<T, R>
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/cache/mod.rs:12:8
[INFO] [stdout]    |
[INFO] [stdout] 12 |     fn new(calculation: T) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `value`
[INFO] [stdout]   --> src/cache/mod.rs:20:8
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fn value<U>(&mut self, arg: U) -> &R
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `value2`
[INFO] [stdout]   --> src/cache/mod.rs:36:8
[INFO] [stdout]    |
[INFO] [stdout] 36 |     fn value2<U>(&mut self, arg: U) -> &R
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `value3`
[INFO] [stdout]   --> src/cache/mod.rs:47:8
[INFO] [stdout]    |
[INFO] [stdout] 47 |     fn value3<U>(&mut self, arg: U) -> &R
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `is_some`
[INFO] [stdout]   --> src/cache/mod.rs:57:8
[INFO] [stdout]    |
[INFO] [stdout] 57 |     fn is_some(&self) -> bool {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `is_none`
[INFO] [stdout]   --> src/cache/mod.rs:64:8
[INFO] [stdout]    |
[INFO] [stdout] 64 |     fn is_none(&self) -> bool {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]  --> src/iterator/mod.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn new() -> Counter {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]  --> src/deref/mod.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn new(x: T) -> MyBox<T> {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `List`
[INFO] [stdout]  --> src/memory/mod.rs:4:6
[INFO] [stdout]   |
[INFO] [stdout] 4 | enum List {
[INFO] [stdout]   |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Cons`
[INFO] [stdout]   --> src/memory/mod.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 |     Cons(T, RefCell<Rc<ListMemoryLeak<T>>>),
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nil`
[INFO] [stdout]   --> src/memory/mod.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     Nil,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `tail`
[INFO] [stdout]   --> src/memory/mod.rs:16:8
[INFO] [stdout]    |
[INFO] [stdout] 16 |     fn tail(&self) -> Option<&RefCell<Rc<ListMemoryLeak<T>>>> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Cons`
[INFO] [stdout]  --> src/rc/mod.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     Cons(T, &'a Box<ListRefVersion<'a, T>>),
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nil`
[INFO] [stdout]  --> src/rc/mod.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     Nil,
[INFO] [stdout]   |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Cons`
[INFO] [stdout]   --> src/rc/mod.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     Cons(T, Rc<ListRcVersion<T>>),
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nil`
[INFO] [stdout]   --> src/rc/mod.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     Nil,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Cons`
[INFO] [stdout]   --> src/rc/mod.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     Cons(Rc<RefCell<T>>, Rc<ListRcRefVersion<T>>),
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nil`
[INFO] [stdout]   --> src/rc/mod.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     Nil,
[INFO] [stdout]    |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `LimitTracker`
[INFO] [stdout]  --> src/ref_demo/mod.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct LimitTracker<'a, T>
[INFO] [stdout]   |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/ref_demo/mod.rs:16:12
[INFO] [stdout]    |
[INFO] [stdout] 16 |     pub fn new(messenger: &'a T, max: usize) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `set_value`
[INFO] [stdout]   --> src/ref_demo/mod.rs:24:12
[INFO] [stdout]    |
[INFO] [stdout] 24 |     pub fn set_value(&mut self, value: usize) {
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/oop_demo/mod.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 24 |     fn new() -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/oop_demo/mod.rs:88:8
[INFO] [stdout]    |
[INFO] [stdout] 88 |     fn new() -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `add_text`
[INFO] [stdout]   --> src/oop_demo/mod.rs:95:12
[INFO] [stdout]    |
[INFO] [stdout] 95 |     pub fn add_text(&mut self, text: &str) {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `content`
[INFO] [stdout]   --> src/oop_demo/mod.rs:99:12
[INFO] [stdout]    |
[INFO] [stdout] 99 |     pub fn content(&self) -> &str {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `request_review`
[INFO] [stdout]    --> src/oop_demo/mod.rs:103:12
[INFO] [stdout]     |
[INFO] [stdout] 103 |     pub fn request_review(&mut self) {
[INFO] [stdout]     |            ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `approve`
[INFO] [stdout]    --> src/oop_demo/mod.rs:109:12
[INFO] [stdout]     |
[INFO] [stdout] 109 |     pub fn approve(&mut self) {
[INFO] [stdout]     |            ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `id`
[INFO] [stdout]   --> src/thread_pool/mod.rs:36:5
[INFO] [stdout]    |
[INFO] [stdout] 36 |     id: usize,
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 34 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::env`
[INFO] [stdout]  --> src/main.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::env;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::process`
[INFO] [stdout]  --> src/main.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::process;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::env`
[INFO] [stdout]  --> src/main.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::env;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::process`
[INFO] [stdout]  --> src/main.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::process;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]   --> src/deref/mod.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |         let z = MyBox::new(String::from("Rust"));
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/memory/mod.rs:33:13
[INFO] [stdout]    |
[INFO] [stdout] 33 |         let b = Cons(3, a.clone());
[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/memory/mod.rs:34:13
[INFO] [stdout]    |
[INFO] [stdout] 34 |         let c = Cons(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/rc/mod.rs:55:13
[INFO] [stdout]    |
[INFO] [stdout] 55 |         let b = Cons(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/rc/mod.rs:58:17
[INFO] [stdout]    |
[INFO] [stdout] 58 |             let c = Cons(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: `producer`
[INFO] [stdout]   --> src/thread_demo/mod.rs:49:13
[INFO] [stdout]    |
[INFO] [stdout] 49 |         let producer = thread::spawn(move || {
[INFO] [stdout]    |             ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_producer`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]  --> src/oop_demo/mod.rs:9:27
[INFO] [stdout]   |
[INFO] [stdout] 9 |     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] 
[INFO] [stdout] warning: associated function is never used: `value`
[INFO] [stdout]   --> src/cache/mod.rs:20:8
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fn value<U>(&mut self, arg: U) -> &R
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `value2`
[INFO] [stdout]   --> src/cache/mod.rs:36:8
[INFO] [stdout]    |
[INFO] [stdout] 36 |     fn value2<U>(&mut self, arg: U) -> &R
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `id`
[INFO] [stdout]   --> src/thread_pool/mod.rs:36:5
[INFO] [stdout]    |
[INFO] [stdout] 36 |     id: usize,
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/print/mod.rs:88:9
[INFO] [stdout]    |
[INFO] [stdout] 88 |         writeln!(&mut some_writer, "{} - {}", 123, 789);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 19 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 17.82s
[INFO] running `Command { std: "docker" "inspect" "a02618b8e3709d014ae269c9514ec19ca36c382c3bf58a62877900d535d4d13d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a02618b8e3709d014ae269c9514ec19ca36c382c3bf58a62877900d535d4d13d", kill_on_drop: false }`
[INFO] [stdout] a02618b8e3709d014ae269c9514ec19ca36c382c3bf58a62877900d535d4d13d