[INFO] cloning repository https://github.com/zachlefevre/rust-learning
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/zachlefevre/rust-learning" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzachlefevre%2Frust-learning", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzachlefevre%2Frust-learning'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6e8771639450277fa7f86da2484b047b58836690
[INFO] checking zachlefevre/rust-learning against master#350d0ef0ec0493e6d21cfb265cb8211a0e74d766 for pr-145342-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzachlefevre%2Frust-learning" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/zachlefevre/rust-learning
[INFO] finished tweaking git repo https://github.com/zachlefevre/rust-learning
[INFO] tweaked toml for git repo https://github.com/zachlefevre/rust-learning written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/zachlefevre/rust-learning on toolchain 350d0ef0ec0493e6d21cfb265cb8211a0e74d766
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+350d0ef0ec0493e6d21cfb265cb8211a0e74d766" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/zachlefevre/rust-learning 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" "+350d0ef0ec0493e6d21cfb265cb8211a0e74d766" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded cc v1.0.104
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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" "+350d0ef0ec0493e6d21cfb265cb8211a0e74d766" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 57be33906576b1b839a43b9d14b03536a1130e79045b171884f44e92a6d7491e
[INFO] running `Command { std: "docker" "start" "-a" "57be33906576b1b839a43b9d14b03536a1130e79045b171884f44e92a6d7491e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "57be33906576b1b839a43b9d14b03536a1130e79045b171884f44e92a6d7491e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "57be33906576b1b839a43b9d14b03536a1130e79045b171884f44e92a6d7491e", kill_on_drop: false }`
[INFO] [stdout] 57be33906576b1b839a43b9d14b03536a1130e79045b171884f44e92a6d7491e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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" "+350d0ef0ec0493e6d21cfb265cb8211a0e74d766" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ff99672b5b9c407950782d0fd831ac9481ddda18013a43411a9a742a13bb38d2
[INFO] running `Command { std: "docker" "start" "-a" "ff99672b5b9c407950782d0fd831ac9481ddda18013a43411a9a742a13bb38d2", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.155
[INFO] [stderr]    Compiling proc-macro2 v1.0.86
[INFO] [stderr]    Compiling unicode-ident v1.0.12
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling autocfg v1.3.0
[INFO] [stderr]    Compiling parking_lot_core v0.9.10
[INFO] [stderr]     Checking smallvec v1.13.2
[INFO] [stderr]     Checking scopeguard v1.2.0
[INFO] [stderr]    Compiling serde v1.0.203
[INFO] [stderr]     Checking ppv-lite86 v0.2.17
[INFO] [stderr]     Checking pin-project-lite v0.2.14
[INFO] [stderr]     Checking bytes v1.6.0
[INFO] [stderr]    Compiling lock_api v0.4.12
[INFO] [stderr]    Compiling quote v1.0.36
[INFO] [stderr]    Compiling syn v2.0.68
[INFO] [stderr]     Checking getrandom v0.2.15
[INFO] [stderr]     Checking num_cpus v1.16.0
[INFO] [stderr]     Checking signal-hook-registry v1.4.2
[INFO] [stderr]     Checking socket2 v0.5.7
[INFO] [stderr]     Checking mio v0.8.11
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking parking_lot v0.12.3
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]    Compiling serde_derive v1.0.203
[INFO] [stderr]    Compiling tokio-macros v2.3.0
[INFO] [stderr]     Checking tokio v1.38.0
[INFO] [stderr]     Checking practice v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around assigned value
[INFO] [stdout]  --> src/bin/btreemap.rs:5:20
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let elements = (0..100);
[INFO] [stdout]   |                    ^      ^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]   |
[INFO] [stdout] 5 -     let elements = (0..100);
[INFO] [stdout] 5 +     let elements = 0..100;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `smallest` is never used
[INFO] [stdout]  --> src/bin/k-smallest.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn smallest(items: impl Iterator<Item = i32>, k: u32) -> Vec<i32> {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `name`
[INFO] [stdout]   --> src/bin/visitor.rs:34:30
[INFO] [stdout]    |
[INFO] [stdout] 34 |     fn visit_name(&mut self, name: &ast::Name) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_name`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `expr`
[INFO] [stdout]   --> src/bin/visitor.rs:38:30
[INFO] [stdout]    |
[INFO] [stdout] 38 |     fn visit_stmt(&mut self, expr: &ast::Stmt) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_expr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `expr`
[INFO] [stdout]   --> src/bin/visitor.rs:42:30
[INFO] [stdout]    |
[INFO] [stdout] 42 |     fn visit_expr(&mut self, expr: &ast::Expr) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_expr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `NoDynamic` is never used
[INFO] [stdout]   --> src/bin/dyn_dispatch.rs:21:7
[INFO] [stdout]    |
[INFO] [stdout] 21 | trait NoDynamic {
[INFO] [stdout]    |       ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `foo` is never used
[INFO] [stdout]   --> src/bin/dyn_dispatch.rs:28:4
[INFO] [stdout]    |
[INFO] [stdout] 28 | fn foo<T>(t: &dyn NoDynamic) {
[INFO] [stdout]    |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Interpreter` is never constructed
[INFO] [stdout]   --> src/bin/visitor.rs:29:8
[INFO] [stdout]    |
[INFO] [stdout] 29 | struct Interpreter {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `main` is never used
[INFO] [stdout]   --> src/bin/visitor.rs:48:4
[INFO] [stdout]    |
[INFO] [stdout] 48 | fn main () {
[INFO] [stdout]    |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Stmt` is never used
[INFO] [stdout]  --> src/bin/visitor.rs:2:14
[INFO] [stdout]   |
[INFO] [stdout] 2 |     pub enum Stmt  {
[INFO] [stdout]   |              ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Name` is never constructed
[INFO] [stdout]  --> src/bin/visitor.rs:7:16
[INFO] [stdout]   |
[INFO] [stdout] 7 |     pub struct Name(String);
[INFO] [stdout]   |                ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Expr` is never used
[INFO] [stdout]  --> src/bin/visitor.rs:9:14
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub enum Expr {
[INFO] [stdout]   |              ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Visitor` is never used
[INFO] [stdout]   --> src/bin/visitor.rs:18:15
[INFO] [stdout]    |
[INFO] [stdout] 18 |     pub trait Visitor<T> {
[INFO] [stdout]    |               ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `TcpSocket` and `task`
[INFO] [stdout]  --> src/bin/service-trait.rs:1:32
[INFO] [stdout]   |
[INFO] [stdout] 1 | use tokio::{net::{TcpListener, TcpSocket, TcpStream}, task};
[INFO] [stdout]   |                                ^^^^^^^^^              ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s1`
[INFO] [stdout]   --> src/bin/strings.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let s1 = String::from(s);
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]   --> src/bin/strings.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let s2 = s.to_owned();
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `EnglishClass` is never constructed
[INFO] [stdout]   --> src/bin/folder.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout]  8 | enum Classroom {
[INFO] [stdout]    |      --------- variant in this enum
[INFO] [stdout]  9 |     ScienceLab { num_beakers: i32, eyewash: bool},
[INFO] [stdout] 10 |     EnglishClass { num_books: i32 }
[INFO] [stdout]    |     ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Classroom` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Bar` is never constructed
[INFO] [stdout]   --> src/bin/oop.rs:12:8
[INFO] [stdout]    |
[INFO] [stdout] 12 | struct Bar;
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Foo` is never constructed
[INFO] [stdout]  --> src/bin/rename-serde.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Foo {
[INFO] [stdout]   |        ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> src/bin/pinning.rs:16:13
[INFO] [stdout]    |
[INFO] [stdout] 16 |         let t: Pin<&Foo> = thing(Pin::new_unchecked(&Foo::new()));
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]  --> src/bin/destructuring.rs:4:14
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let (ref a, b) = *t;
[INFO] [stdout]   |              ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> src/bin/destructuring.rs:4:17
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let (ref a, b) = *t;
[INFO] [stdout]   |                 ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/bin/destructuring.rs:12:14
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let (ref a, b) = t;
[INFO] [stdout]    |              ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/bin/destructuring.rs:12:17
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let (ref a, b) = t;
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `one` is never used
[INFO] [stdout]  --> src/bin/destructuring.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn one() {
[INFO] [stdout]   |    ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `two` is never used
[INFO] [stdout]  --> src/bin/destructuring.rs:9:4
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn two() {
[INFO] [stdout]   |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::iter::Chain` that must be used
[INFO] [stdout]  --> src/bin/chain.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 |     dbg!(vec![1, 2, 3, 4, 5].iter().chain(Some(8).iter()));
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: iterators are lazy and do nothing unless consumed
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 2 |     let _ = dbg!(vec![1, 2, 3, 4, 5].iter().chain(Some(8).iter()));
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `sound` is never used
[INFO] [stdout]  --> src/bin/dispatches.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait Animal {
[INFO] [stdout]   |       ------ method in this trait
[INFO] [stdout] 2 |     fn sound(&self) -> String;
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/files.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |         dbg!(String::from_utf8(buf.to_vec()));
[INFO] [stdout]   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 9 |         let _ = dbg!(String::from_utf8(buf.to_vec()));
[INFO] [stdout]   |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `response`
[INFO] [stdout]   --> src/bin/service-trait.rs:33:18
[INFO] [stdout]    |
[INFO] [stdout] 33 | fn respond_error(response: std::io::Error, socket: &TcpStream) {
[INFO] [stdout]    |                  ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_response`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `socket`
[INFO] [stdout]   --> src/bin/service-trait.rs:33:44
[INFO] [stdout]    |
[INFO] [stdout] 33 | fn respond_error(response: std::io::Error, socket: &TcpStream) {
[INFO] [stdout]    |                                            ^^^^^^ help: if this is intentional, prefix it with an underscore: `_socket`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `response`
[INFO] [stdout]   --> src/bin/service-trait.rs:36:12
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn respond(response: Response, socket: &TcpStream) {
[INFO] [stdout]    |            ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_response`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `socket`
[INFO] [stdout]   --> src/bin/service-trait.rs:36:32
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn respond(response: Response, socket: &TcpStream) {
[INFO] [stdout]    |                                ^^^^^^ help: if this is intentional, prefix it with an underscore: `_socket`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `socket`
[INFO] [stdout]   --> src/bin/service-trait.rs:41:17
[INFO] [stdout]    |
[INFO] [stdout] 41 | fn make_request(socket: &TcpStream) -> Request {
[INFO] [stdout]    |                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_socket`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Server` is never constructed
[INFO] [stdout]  --> src/bin/service-trait.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Server {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Request` is never constructed
[INFO] [stdout]  --> src/bin/service-trait.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 9 | struct Request;
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Response` is never constructed
[INFO] [stdout]   --> src/bin/service-trait.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | struct Response;
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `run` is never used
[INFO] [stdout]   --> src/bin/service-trait.rs:14:14
[INFO] [stdout]    |
[INFO] [stdout] 13 | impl Server {
[INFO] [stdout]    | ----------- method in this implementation
[INFO] [stdout] 14 |     async fn run<F, Fut>(self, handler: F) -> Result<(), std::io::Error>
[INFO] [stdout]    |              ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `respond_error` is never used
[INFO] [stdout]   --> src/bin/service-trait.rs:33:4
[INFO] [stdout]    |
[INFO] [stdout] 33 | fn respond_error(response: std::io::Error, socket: &TcpStream) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `respond` is never used
[INFO] [stdout]   --> src/bin/service-trait.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn respond(response: Response, socket: &TcpStream) {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `make_request` is never used
[INFO] [stdout]   --> src/bin/service-trait.rs:41:4
[INFO] [stdout]    |
[INFO] [stdout] 41 | fn make_request(socket: &TcpStream) -> Request {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated type alias `std::panic::PanicInfo`: use `PanicHookInfo` instead
[INFO] [stdout]  --> src/bin/panic_handler.rs:1:17
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::panic::PanicInfo;
[INFO] [stdout]   |                 ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated type alias `std::panic::PanicInfo`: use `PanicHookInfo` instead
[INFO] [stdout]  --> src/bin/panic_handler.rs:5:25
[INFO] [stdout]   |
[INFO] [stdout] 5 | fn panic_handler(info: &PanicInfo) -> ! {
[INFO] [stdout]   |                         ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `info`
[INFO] [stdout]  --> src/bin/panic_handler.rs:5:18
[INFO] [stdout]   |
[INFO] [stdout] 5 | fn panic_handler(info: &PanicInfo) -> ! {
[INFO] [stdout]   |                  ^^^^ help: if this is intentional, prefix it with an underscore: `_info`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `panic_handler` is never used
[INFO] [stdout]  --> src/bin/panic_handler.rs:5:4
[INFO] [stdout]   |
[INFO] [stdout] 5 | fn panic_handler(info: &PanicInfo) -> ! {
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Write`
[INFO] [stdout]  --> src/bin/vec_fns.rs:1:41
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io::{BufReader, self, BufRead, Write, Read};
[INFO] [stdout]   |                                         ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Bar` is never constructed
[INFO] [stdout]   --> src/bin/oop.rs:12:8
[INFO] [stdout]    |
[INFO] [stdout] 12 | struct Bar;
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `name`
[INFO] [stdout]   --> src/bin/visitor.rs:34:30
[INFO] [stdout]    |
[INFO] [stdout] 34 |     fn visit_name(&mut self, name: &ast::Name) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_name`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]  --> src/bin/vec_fns.rs:9:13
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut s = String::new();
[INFO] [stdout]   |             ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `expr`
[INFO] [stdout]   --> src/bin/visitor.rs:38:30
[INFO] [stdout]    |
[INFO] [stdout] 38 |     fn visit_stmt(&mut self, expr: &ast::Stmt) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_expr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `expr`
[INFO] [stdout]   --> src/bin/visitor.rs:42:30
[INFO] [stdout]    |
[INFO] [stdout] 42 |     fn visit_expr(&mut self, expr: &ast::Expr) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_expr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `NoDynamic` is never used
[INFO] [stdout]   --> src/bin/dyn_dispatch.rs:21:7
[INFO] [stdout]    |
[INFO] [stdout] 21 | trait NoDynamic {
[INFO] [stdout]    |       ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `foo` is never used
[INFO] [stdout]   --> src/bin/dyn_dispatch.rs:28:4
[INFO] [stdout]    |
[INFO] [stdout] 28 | fn foo<T>(t: &dyn NoDynamic) {
[INFO] [stdout]    |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Interpreter` is never constructed
[INFO] [stdout]   --> src/bin/visitor.rs:29:8
[INFO] [stdout]    |
[INFO] [stdout] 29 | struct Interpreter {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `main` is never used
[INFO] [stdout]   --> src/bin/visitor.rs:48:4
[INFO] [stdout]    |
[INFO] [stdout] 48 | fn main () {
[INFO] [stdout]    |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Stmt` is never used
[INFO] [stdout]  --> src/bin/visitor.rs:2:14
[INFO] [stdout]   |
[INFO] [stdout] 2 |     pub enum Stmt  {
[INFO] [stdout]   |              ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Name` is never constructed
[INFO] [stdout]  --> src/bin/visitor.rs:7:16
[INFO] [stdout]   |
[INFO] [stdout] 7 |     pub struct Name(String);
[INFO] [stdout]   |                ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Expr` is never used
[INFO] [stdout]  --> src/bin/visitor.rs:9:14
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub enum Expr {
[INFO] [stdout]   |              ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Visitor` is never used
[INFO] [stdout]   --> src/bin/visitor.rs:18:15
[INFO] [stdout]    |
[INFO] [stdout] 18 |     pub trait Visitor<T> {
[INFO] [stdout]    |               ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/bin/vec_fns.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let mut file = std::fs::File::open("vec_fns.rs").unwrap();
[INFO] [stdout]   |         ----^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/bin/vec_fns.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut s = String::new();
[INFO] [stdout]   |         ----^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/vec_fns.rs:14:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     bufreader.read_until(b'B', &mut v);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let _ = bufreader.read_until(b'B', &mut v);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/vec_fns.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     dbg!(String::from_utf8(v));
[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] 17 |     let _ = dbg!(String::from_utf8(v));
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/vec_fns.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     io::copy(&mut bufreader, &mut io::stderr());
[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] 19 |     let _ = io::copy(&mut bufreader, &mut io::stderr());
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/stdout.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     stdout.write_all(&v[..]);
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let _ = stdout.write_all(&v[..]);
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/stdout.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     stdout.write_all(v2);
[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] 9 |     let _ = stdout.write_all(v2);
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/3-channel-consume.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     t1.send(1).await;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let _ = t1.send(1).await;
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/3-channel-consume.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 |     t2.send(2).await;
[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] 8 |     let _ = t2.send(2).await;
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/3-channel-consume.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     t3.send(3).await;
[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] 9 |     let _ = t3.send(3).await;
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/stdout.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     stdout.write_all(&v3[..]);
[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] 12 |     let _ = stdout.write_all(&v3[..]);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/stdout.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 |     write!(stdout, "write! writes a string literal\n");
[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] 15 |     let _ = write!(stdout, "write! writes a string literal\n");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/stdout.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     write!(stdout, "{}", s);
[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] 17 |     let _ = write!(stdout, "{}", s);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `TcpSocket` and `task`
[INFO] [stdout]  --> src/bin/service-trait.rs:1:32
[INFO] [stdout]   |
[INFO] [stdout] 1 | use tokio::{net::{TcpListener, TcpSocket, TcpStream}, task};
[INFO] [stdout]   |                                ^^^^^^^^^              ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Write`
[INFO] [stdout]  --> src/bin/vec_fns.rs:1:41
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io::{BufReader, self, BufRead, Write, Read};
[INFO] [stdout]   |                                         ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `response`
[INFO] [stdout]   --> src/bin/service-trait.rs:33:18
[INFO] [stdout]    |
[INFO] [stdout] 33 | fn respond_error(response: std::io::Error, socket: &TcpStream) {
[INFO] [stdout]    |                  ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_response`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `socket`
[INFO] [stdout]   --> src/bin/service-trait.rs:33:44
[INFO] [stdout]    |
[INFO] [stdout] 33 | fn respond_error(response: std::io::Error, socket: &TcpStream) {
[INFO] [stdout]    |                                            ^^^^^^ help: if this is intentional, prefix it with an underscore: `_socket`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `response`
[INFO] [stdout]   --> src/bin/service-trait.rs:36:12
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn respond(response: Response, socket: &TcpStream) {
[INFO] [stdout]    |            ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_response`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `socket`
[INFO] [stdout]   --> src/bin/service-trait.rs:36:32
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn respond(response: Response, socket: &TcpStream) {
[INFO] [stdout]    |                                ^^^^^^ help: if this is intentional, prefix it with an underscore: `_socket`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `socket`
[INFO] [stdout]   --> src/bin/service-trait.rs:41:17
[INFO] [stdout]    |
[INFO] [stdout] 41 | fn make_request(socket: &TcpStream) -> Request {
[INFO] [stdout]    |                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_socket`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Server` is never constructed
[INFO] [stdout]  --> src/bin/service-trait.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Server {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Request` is never constructed
[INFO] [stdout]  --> src/bin/service-trait.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 9 | struct Request;
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Response` is never constructed
[INFO] [stdout]   --> src/bin/service-trait.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | struct Response;
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `run` is never used
[INFO] [stdout]   --> src/bin/service-trait.rs:14:14
[INFO] [stdout]    |
[INFO] [stdout] 13 | impl Server {
[INFO] [stdout]    | ----------- method in this implementation
[INFO] [stdout] 14 |     async fn run<F, Fut>(self, handler: F) -> Result<(), std::io::Error>
[INFO] [stdout]    |              ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `respond_error` is never used
[INFO] [stdout]   --> src/bin/service-trait.rs:33:4
[INFO] [stdout]    |
[INFO] [stdout] 33 | fn respond_error(response: std::io::Error, socket: &TcpStream) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `respond` is never used
[INFO] [stdout]   --> src/bin/service-trait.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn respond(response: Response, socket: &TcpStream) {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `make_request` is never used
[INFO] [stdout]   --> src/bin/service-trait.rs:41:4
[INFO] [stdout]    |
[INFO] [stdout] 41 | fn make_request(socket: &TcpStream) -> Request {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]  --> src/bin/atomics.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let a = AtomicBool::new(true);
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]  --> src/bin/vec_fns.rs:9:13
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut s = String::new();
[INFO] [stdout]   |             ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/bin/vec_fns.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let mut file = std::fs::File::open("vec_fns.rs").unwrap();
[INFO] [stdout]   |         ----^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/bin/vec_fns.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut s = String::new();
[INFO] [stdout]   |         ----^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around assigned value
[INFO] [stdout]  --> src/bin/btreemap.rs:5:20
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let elements = (0..100);
[INFO] [stdout]   |                    ^      ^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]   |
[INFO] [stdout] 5 -     let elements = (0..100);
[INFO] [stdout] 5 +     let elements = 0..100;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/vec_fns.rs:14:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     bufreader.read_until(b'B', &mut v);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let _ = bufreader.read_until(b'B', &mut v);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/vec_fns.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     dbg!(String::from_utf8(v));
[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] 17 |     let _ = dbg!(String::from_utf8(v));
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/vec_fns.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     io::copy(&mut bufreader, &mut io::stderr());
[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] 19 |     let _ = io::copy(&mut bufreader, &mut io::stderr());
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` in tuple element 0 that must be used
[INFO] [stdout]   --> src/bin/join.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     dbg!(tokio::join!(tokio::spawn(a), tokio::spawn(b), tokio::spawn(c)));
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `status`
[INFO] [stdout]  --> src/bin/commands.rs:6:17
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let Output {status, stdout, stderr } = Command::new("ls").output().expect("ls?");
[INFO] [stdout]   |                 ^^^^^^ help: try ignoring the field: `status: _`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `stderr`
[INFO] [stdout]  --> src/bin/commands.rs:6:33
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let Output {status, stdout, stderr } = Command::new("ls").output().expect("ls?");
[INFO] [stdout]   |                                 ^^^^^^ help: try ignoring the field: `stderr: _`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` in tuple element 1 that must be used
[INFO] [stdout]   --> src/bin/join.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     dbg!(tokio::join!(tokio::spawn(a), tokio::spawn(b), tokio::spawn(c)));
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` in tuple element 2 that must be used
[INFO] [stdout]   --> src/bin/join.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     dbg!(tokio::join!(tokio::spawn(a), tokio::spawn(b), tokio::spawn(c)));
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/commands.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     dbg!(String::from_utf8(stdout));
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let _ = dbg!(String::from_utf8(stdout));
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Chunks` that must be used
[INFO] [stdout]  --> src/bin/chunk.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 |     dbg!(vec![1, 2, 3, 4, 5, 6, 7, 8].chunks(3));
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: iterators are lazy and do nothing unless consumed
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 2 |     let _ = dbg!(vec![1, 2, 3, 4, 5, 6, 7, 8].chunks(3));
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> src/bin/typeclasses.rs:62:17
[INFO] [stdout]    |
[INFO] [stdout] 62 |             let s = ai.0;
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `FileDownloadRequest` is never constructed
[INFO] [stdout]   --> src/bin/typeclasses.rs:54:12
[INFO] [stdout]    |
[INFO] [stdout] 54 |     struct FileDownloadRequest<P: protocol::Protocol> {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `mount_point` is never used
[INFO] [stdout]   --> src/bin/typeclasses.rs:59:12
[INFO] [stdout]    |
[INFO] [stdout] 58 |     impl FileDownloadRequest<protocol::Nfs> {
[INFO] [stdout]    |     --------------------------------------- method in this implementation
[INFO] [stdout] 59 |         fn mount_point(&self) -> &String {
[INFO] [stdout]    |            ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `other` is never used
[INFO] [stdout]   --> src/bin/typeclasses.rs:68:12
[INFO] [stdout]    |
[INFO] [stdout] 67 |     impl FileDownloadRequest<protocol::Bootp> {
[INFO] [stdout]    |     ----------------------------------------- method in this implementation
[INFO] [stdout] 68 |         fn other(&self) -> i32 {
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `AuthInfo` is never constructed
[INFO] [stdout]  --> src/bin/typeclasses.rs:6:20
[INFO] [stdout]   |
[INFO] [stdout] 6 |         pub struct AuthInfo(pub String);
[INFO] [stdout]   |                    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `AuthInfo` is never constructed
[INFO] [stdout]   --> src/bin/typeclasses.rs:10:20
[INFO] [stdout]    |
[INFO] [stdout] 10 |         pub struct AuthInfo(pub i32);
[INFO] [stdout]    |                    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `TransferParameters` is never constructed
[INFO] [stdout]   --> src/bin/typeclasses.rs:17:20
[INFO] [stdout]    |
[INFO] [stdout] 17 |         pub struct TransferParameters {
[INFO] [stdout]    |                    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Protocol` is never used
[INFO] [stdout]   --> src/bin/typeclasses.rs:22:19
[INFO] [stdout]    |
[INFO] [stdout] 22 |         pub trait Protocol {
[INFO] [stdout]    |                   ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Nfs` is never constructed
[INFO] [stdout]   --> src/bin/typeclasses.rs:28:20
[INFO] [stdout]    |
[INFO] [stdout] 28 |         pub struct Nfs {
[INFO] [stdout]    |                    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Bootp` is never constructed
[INFO] [stdout]   --> src/bin/typeclasses.rs:41:20
[INFO] [stdout]    |
[INFO] [stdout] 41 |         pub struct Bootp;
[INFO] [stdout]    |                    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]  --> src/bin/destructuring.rs:4:14
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let (ref a, b) = *t;
[INFO] [stdout]   |              ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> src/bin/destructuring.rs:4:17
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let (ref a, b) = *t;
[INFO] [stdout]   |                 ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/bin/destructuring.rs:12:14
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let (ref a, b) = t;
[INFO] [stdout]    |              ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/bin/destructuring.rs:12:17
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let (ref a, b) = t;
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `one` is never used
[INFO] [stdout]  --> src/bin/destructuring.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn one() {
[INFO] [stdout]   |    ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `two` is never used
[INFO] [stdout]  --> src/bin/destructuring.rs:9:4
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn two() {
[INFO] [stdout]   |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `name`
[INFO] [stdout]   --> src/bin/visitor.rs:34:30
[INFO] [stdout]    |
[INFO] [stdout] 34 |     fn visit_name(&mut self, name: &ast::Name) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_name`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `expr`
[INFO] [stdout]   --> src/bin/visitor.rs:38:30
[INFO] [stdout]    |
[INFO] [stdout] 38 |     fn visit_stmt(&mut self, expr: &ast::Stmt) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_expr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `expr`
[INFO] [stdout]   --> src/bin/visitor.rs:42:30
[INFO] [stdout]    |
[INFO] [stdout] 42 |     fn visit_expr(&mut self, expr: &ast::Expr) -> i64 {
[INFO] [stdout]    |                              ^^^^ help: if this is intentional, prefix it with an underscore: `_expr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Interpreter` is never constructed
[INFO] [stdout]   --> src/bin/visitor.rs:29:8
[INFO] [stdout]    |
[INFO] [stdout] 29 | struct Interpreter {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Stmt` is never used
[INFO] [stdout]  --> src/bin/visitor.rs:2:14
[INFO] [stdout]   |
[INFO] [stdout] 2 |     pub enum Stmt  {
[INFO] [stdout]   |              ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Name` is never constructed
[INFO] [stdout]  --> src/bin/visitor.rs:7:16
[INFO] [stdout]   |
[INFO] [stdout] 7 |     pub struct Name(String);
[INFO] [stdout]   |                ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Expr` is never used
[INFO] [stdout]  --> src/bin/visitor.rs:9:14
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub enum Expr {
[INFO] [stdout]   |              ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Visitor` is never used
[INFO] [stdout]   --> src/bin/visitor.rs:18:15
[INFO] [stdout]    |
[INFO] [stdout] 18 |     pub trait Visitor<T> {
[INFO] [stdout]    |               ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]  --> src/bin/select-most-recent.rs:7:14
[INFO] [stdout]   |
[INFO] [stdout] 7 |         Some(v) => Some("foo".into())
[INFO] [stdout]   |              ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ffi::OsString`
[INFO] [stdout]  --> src/bin/paths.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{env, ffi::OsString, path::{Path, PathBuf}};
[INFO] [stdout]   |                ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `p`
[INFO] [stdout]  --> src/bin/paths.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn foo(p: PathBuf) {
[INFO] [stdout]   |        ^ help: if this is intentional, prefix it with an underscore: `_p`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]  --> src/bin/paths.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let home = env::home_dir();
[INFO] [stdout]   |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `foo` is never used
[INFO] [stdout]  --> src/bin/paths.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn foo(p: PathBuf) {
[INFO] [stdout]   |    ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]  --> src/bin/operators.rs:8:27
[INFO] [stdout]   |
[INFO] [stdout] 8 |     fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> { todo!() }
[INFO] [stdout]   |                           ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Foo` is never constructed
[INFO] [stdout]  --> src/bin/operators.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | struct Foo;
[INFO] [stdout]   |        ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]  --> src/bin/index.rs:8:21
[INFO] [stdout]   |
[INFO] [stdout] 8 |     fn index(&self, i: f32) -> &Self:: Output {
[INFO] [stdout]   |                     ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> src/bin/asref.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let b = a.as_ref();
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/files.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |         dbg!(String::from_utf8(buf.to_vec()));
[INFO] [stdout]   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 9 |         let _ = dbg!(String::from_utf8(buf.to_vec()));
[INFO] [stdout]   |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]  --> src/bin/operators.rs:8:27
[INFO] [stdout]   |
[INFO] [stdout] 8 |     fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> { todo!() }
[INFO] [stdout]   |                           ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Foo` is never constructed
[INFO] [stdout]  --> src/bin/operators.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | struct Foo;
[INFO] [stdout]   |        ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]  --> src/bin/options.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let value = op.unwrap_or(18);
[INFO] [stdout]   |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `value`
[INFO] [stdout]  --> src/bin/options.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let value = op.unwrap_or("hey there".to_string());
[INFO] [stdout]   |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_value`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]  --> src/bin/atomics.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let a = AtomicBool::new(true);
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> src/bin/pinning.rs:16:13
[INFO] [stdout]    |
[INFO] [stdout] 16 |         let t: Pin<&Foo> = thing(Pin::new_unchecked(&Foo::new()));
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `chained`
[INFO] [stdout]   --> src/bin/iterators.rs:43:9
[INFO] [stdout]    |
[INFO] [stdout] 43 |     let chained = a.into_iter().chain(b);
[INFO] [stdout]    |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_chained`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the trait bound `[_; 0]: std::io::Read` is not satisfied
[INFO] [stdout]  --> src/bin/bufread_test.rs:7:37
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let mut reader = BufReader::new(input);
[INFO] [stdout]   |                      -------------- ^^^^^ the trait `std::io::Read` is not implemented for `[_; 0]`
[INFO] [stdout]   |                      |
[INFO] [stdout]   |                      required by a bound introduced by this call
[INFO] [stdout]   |
[INFO] [stdout]   = help: the trait `std::io::Read` is implemented for `&[u8]`
[INFO] [stdout] note: required by a bound in `BufReader::<R>::new`
[INFO] [stdout]  --> /rustc/350d0ef0ec0493e6d21cfb265cb8211a0e74d766/library/std/src/io/buffered/bufreader.rs:73:5
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: the method `read_line` exists for struct `BufReader<[_; 0]>`, but its trait bounds were not satisfied
[INFO] [stdout]   --> src/bin/bufread_test.rs:13:26
[INFO] [stdout]    |
[INFO] [stdout] 13 |     while let _ = reader.read_line(&mut buf).unwrap() {
[INFO] [stdout]    |                          ^^^^^^^^^ method cannot be called on `BufReader<[_; 0]>` due to unsatisfied trait bounds
[INFO] [stdout]    |
[INFO] [stdout]    = note: the following trait bounds were not satisfied:
[INFO] [stdout]            `[_; 0]: std::io::Read`
[INFO] [stdout]            which is required by `BufReader<[_; 0]>: BufRead`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the trait bound `[_; 0]: std::io::Read` is not satisfied
[INFO] [stdout]  --> src/bin/bufread_test.rs:7:37
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let mut reader = BufReader::new(input);
[INFO] [stdout]   |                      -------------- ^^^^^ the trait `std::io::Read` is not implemented for `[_; 0]`
[INFO] [stdout]   |                      |
[INFO] [stdout]   |                      required by a bound introduced by this call
[INFO] [stdout]   |
[INFO] [stdout]   = help: the trait `std::io::Read` is implemented for `&[u8]`
[INFO] [stdout] note: required by a bound in `BufReader::<R>::new`
[INFO] [stdout]  --> /rustc/350d0ef0ec0493e6d21cfb265cb8211a0e74d766/library/std/src/io/buffered/bufreader.rs:73:5
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Column`
[INFO] [stdout]   --> src/bin/parser.rs:62:21
[INFO] [stdout]    |
[INFO] [stdout] 62 |     use self::ast::{Column, FromTarget, Select, SelectTarget};
[INFO] [stdout]    |                     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/bin/choose_weighted.rs:5:4
[INFO] [stdout]   |
[INFO] [stdout] 5 |    dbg!(v.choose_weighted(&mut rand::thread_rng(), |x| *x));
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]   = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 5 |    let _ = dbg!(v.choose_weighted(&mut rand::thread_rng(), |x| *x));
[INFO] [stdout]   |    +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0599.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Foo` is never constructed
[INFO] [stdout]  --> src/bin/rename-serde.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Foo {
[INFO] [stdout]   |        ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `practice` (bin "bufread_test" test) due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/bin/iterators.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 35 |     dbg!(a);
[INFO] [stdout]    |     ^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 35 |     let _ = dbg!(a);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]  --> src/bin/memtake.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let n = std::mem::replace(&mut p1.name, "foo".to_string());
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]  --> src/bin/memtake.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let a = std::mem::take(&mut p1.age);
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `EnglishClass` is never constructed
[INFO] [stdout]   --> src/bin/folder.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout]  8 | enum Classroom {
[INFO] [stdout]    |      --------- variant in this enum
[INFO] [stdout]  9 |     ScienceLab { num_beakers: i32, eyewash: bool},
[INFO] [stdout] 10 |     EnglishClass { num_books: i32 }
[INFO] [stdout]    |     ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Classroom` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `m`
[INFO] [stdout]   --> src/bin/lifetimes.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let m = &array[0]; // just borrow out of the vector of strings
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_m`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/bin/lifetimes.rs:27:14
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (ref a, ref b) = t;
[INFO] [stdout]    |              ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/bin/lifetimes.rs:27:21
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (ref a, ref b) = t;
[INFO] [stdout]    |                     ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `m`
[INFO] [stdout]   --> src/bin/lifetimes.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let m = &array[0]; // just borrow out of the vector of strings
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_m`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/bin/lifetimes.rs:27:14
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (ref a, ref b) = t;
[INFO] [stdout]    |              ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/bin/lifetimes.rs:27:21
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let (ref a, ref b) = t;
[INFO] [stdout]    |                     ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]   --> src/bin/lifetimes.rs:62:17
[INFO] [stdout]    |
[INFO] [stdout] 62 |             let n = v;
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: the method `read_line` exists for struct `BufReader<[_; 0]>`, but its trait bounds were not satisfied
[INFO] [stdout]   --> src/bin/bufread_test.rs:13:26
[INFO] [stdout]    |
[INFO] [stdout] 13 |     while let _ = reader.read_line(&mut buf).unwrap() {
[INFO] [stdout]    |                          ^^^^^^^^^ method cannot be called on `BufReader<[_; 0]>` due to unsatisfied trait bounds
[INFO] [stdout]    |
[INFO] [stdout]    = note: the following trait bounds were not satisfied:
[INFO] [stdout]            `[_; 0]: std::io::Read`
[INFO] [stdout]            which is required by `BufReader<[_; 0]>: BufRead`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Person` is never constructed
[INFO] [stdout]  --> src/bin/lifetimes.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Person {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]   --> src/bin/lifetimes.rs:62:17
[INFO] [stdout]    |
[INFO] [stdout] 62 |             let n = v;
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `name` is never read
[INFO] [stdout]  --> src/bin/lifetimes.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct Person2<'a> {
[INFO] [stdout]   |        ------- field in this struct
[INFO] [stdout] 9 |     name: &'a str
[INFO] [stdout]   |     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Person2` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_func` is never used
[INFO] [stdout]   --> src/bin/lifetimes.rs:58:4
[INFO] [stdout]    |
[INFO] [stdout] 58 | fn some_func(i: &Option<String>) -> Option<()> {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Person` is never constructed
[INFO] [stdout]  --> src/bin/lifetimes.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Person {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `name` is never read
[INFO] [stdout]  --> src/bin/lifetimes.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct Person2<'a> {
[INFO] [stdout]   |        ------- field in this struct
[INFO] [stdout] 9 |     name: &'a str
[INFO] [stdout]   |     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Person2` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `some_func` is never used
[INFO] [stdout]   --> src/bin/lifetimes.rs:58:4
[INFO] [stdout]    |
[INFO] [stdout] 58 | fn some_func(i: &Option<String>) -> Option<()> {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: path statement with no effect
[INFO] [stdout]   --> src/bin/lifetimes.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 |     thing;
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(path_statements)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: path statement with no effect
[INFO] [stdout]   --> src/bin/lifetimes.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 |     thing;
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(path_statements)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0599.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `practice` (bin "bufread_test") due to 2 previous errors
[INFO] [stdout] error[E0502]: cannot borrow `*self` as mutable because it is also borrowed as immutable
[INFO] [stdout]    --> src/bin/parser.rs:130:17
[INFO] [stdout]     |
[INFO] [stdout] 129 |                 let column_name = self.current_token()?.as_identifier().unwrap();
[INFO] [stdout]     |                                   ---- immutable borrow occurs here
[INFO] [stdout] 130 |                 self.advance();
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^ mutable borrow occurs here
[INFO] [stdout] ...
[INFO] [stdout] 135 |                         return Ok(ast::Column(column_name.to_string(), Some(alias_name.to_string())))
[INFO] [stdout]     |                                               ----------- immutable borrow later used here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0502]: cannot borrow `*self` as mutable because it is also borrowed as immutable
[INFO] [stdout]    --> src/bin/parser.rs:132:21
[INFO] [stdout]     |
[INFO] [stdout] 129 |                 let column_name = self.current_token()?.as_identifier().unwrap();
[INFO] [stdout]     |                                   ---- immutable borrow occurs here
[INFO] [stdout] ...
[INFO] [stdout] 132 |                     self.advance();
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^ mutable borrow occurs here
[INFO] [stdout] ...
[INFO] [stdout] 135 |                         return Ok(ast::Column(column_name.to_string(), Some(alias_name.to_string())))
[INFO] [stdout]     |                                               ----------- immutable borrow later used here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `identifier`
[INFO] [stdout]    --> src/bin/parser.rs:153:42
[INFO] [stdout]     |
[INFO] [stdout] 153 |                     Ok(Token::Identifier(identifier)) => {
[INFO] [stdout]     |                                          ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_identifier`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0502`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `practice` (bin "parser") due to 2 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "ff99672b5b9c407950782d0fd831ac9481ddda18013a43411a9a742a13bb38d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ff99672b5b9c407950782d0fd831ac9481ddda18013a43411a9a742a13bb38d2", kill_on_drop: false }`
[INFO] [stdout] ff99672b5b9c407950782d0fd831ac9481ddda18013a43411a9a742a13bb38d2