[INFO] cloning repository https://github.com/modulitos/async_book
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/modulitos/async_book" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2Fasync_book", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2Fasync_book'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a9f98e52ed4f718fe4814f7a36bcb8741da5328e
[INFO] checking modulitos/async_book against try#8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8 for pr-82565
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2Fasync_book" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/modulitos/async_book on toolchain 8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/modulitos/async_book
[INFO] finished tweaking git repo https://github.com/modulitos/async_book
[INFO] tweaked toml for git repo https://github.com/modulitos/async_book written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/modulitos/async_book already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 41963b4f201c379eef15df3619c69bdb0133ce442e2d008e8e321fe8abb248dc
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "41963b4f201c379eef15df3619c69bdb0133ce442e2d008e8e321fe8abb248dc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "41963b4f201c379eef15df3619c69bdb0133ce442e2d008e8e321fe8abb248dc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "41963b4f201c379eef15df3619c69bdb0133ce442e2d008e8e321fe8abb248dc", kill_on_drop: false }`
[INFO] [stdout] 41963b4f201c379eef15df3619c69bdb0133ce442e2d008e8e321fe8abb248dc
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] daa8bb6ae169fa5abd7a4a60d4bd3c75ad5588331bfcb2c88857cd0368b6f8b7
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "daa8bb6ae169fa5abd7a4a60d4bd3c75ad5588331bfcb2c88857cd0368b6f8b7", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.39
[INFO] [stderr]     Checking pin-project-lite v0.1.7
[INFO] [stderr]     Checking bytes v0.5.6
[INFO] [stderr]     Checking futures-channel v0.3.5
[INFO] [stderr]    Compiling pin-project-internal v0.4.23
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]     Checking tokio v0.2.22
[INFO] [stderr]     Checking pin-project v0.4.23
[INFO] [stderr]     Checking futures-util v0.3.5
[INFO] [stderr]     Checking futures-executor v0.3.5
[INFO] [stderr]     Checking futures v0.3.5
[INFO] [stderr]     Checking async_book v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: type does not implement `Debug`; consider adding `#[derive(Debug)]` or a manual implementation
[INFO] [stdout]   --> src/executor.rs:17:1
[INFO] [stdout]    |
[INFO] [stdout] 17 | / pub struct Executor {
[INFO] [stdout] 18 | |     ready_queue: Receiver<Arc<Task>>,
[INFO] [stdout] 19 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/lib.rs:3:5
[INFO] [stdout]    |
[INFO] [stdout] 3  |     missing_debug_implementations,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type does not implement `Debug`; consider adding `#[derive(Debug)]` or a manual implementation
[INFO] [stdout]   --> src/executor.rs:22:1
[INFO] [stdout]    |
[INFO] [stdout] 22 | / pub struct Spawner {
[INFO] [stdout] 23 | |     task_sender: SyncSender<Arc<Task>>,
[INFO] [stdout] 24 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type does not implement `Debug`; consider adding `#[derive(Debug)]` or a manual implementation
[INFO] [stdout]   --> src/executor.rs:17:1
[INFO] [stdout]    |
[INFO] [stdout] 17 | / pub struct Executor {
[INFO] [stdout] 18 | |     ready_queue: Receiver<Arc<Task>>,
[INFO] [stdout] 19 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/lib.rs:3:5
[INFO] [stdout]    |
[INFO] [stdout] 3  |     missing_debug_implementations,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type does not implement `Debug`; consider adding `#[derive(Debug)]` or a manual implementation
[INFO] [stdout]   --> src/executor.rs:22:1
[INFO] [stdout]    |
[INFO] [stdout] 22 | / pub struct Spawner {
[INFO] [stdout] 23 | |     task_sender: SyncSender<Arc<Task>>,
[INFO] [stdout] 24 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/bin/ch_4_pinning.rs:11:8
[INFO] [stdout]    |
[INFO] [stdout] 11 |     fn new(txt: &str) -> Self {
[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: `init`
[INFO] [stdout]   --> src/bin/ch_4_pinning.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 |     fn init(&mut self) {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `a`
[INFO] [stdout]   --> src/bin/ch_4_pinning.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn a(&self) -> &str {
[INFO] [stdout]    |        ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `b`
[INFO] [stdout]   --> src/bin/ch_4_pinning.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 |     fn b(&self) -> &String {
[INFO] [stdout]    |        ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/bin/ch_4_pinning.rs:63:8
[INFO] [stdout]    |
[INFO] [stdout] 63 |     fn new(txt: &str) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `init`
[INFO] [stdout]   --> src/bin/ch_4_pinning.rs:70:8
[INFO] [stdout]    |
[INFO] [stdout] 70 |     fn init(self: Pin<&mut Self>) {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `a`
[INFO] [stdout]   --> src/bin/ch_4_pinning.rs:76:8
[INFO] [stdout]    |
[INFO] [stdout] 76 |     fn a(self: Pin<&'_ Self>) -> &'_ str {
[INFO] [stdout]    |        ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `b`
[INFO] [stdout]   --> src/bin/ch_4_pinning.rs:80:8
[INFO] [stdout]    |
[INFO] [stdout] 80 |     fn b(self: Pin<&'_ Self>) -> &'_ String {
[INFO] [stdout]    |        ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]    --> src/bin/ch_4_pinning.rs:125:8
[INFO] [stdout]     |
[INFO] [stdout] 125 |     fn new(txt: &str) -> Pin<Box<Self>> {
[INFO] [stdout]     |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `a`
[INFO] [stdout]    --> src/bin/ch_4_pinning.rs:143:8
[INFO] [stdout]     |
[INFO] [stdout] 143 |     fn a(&self) -> &str {
[INFO] [stdout]     |        ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `b`
[INFO] [stdout]    --> src/bin/ch_4_pinning.rs:147:8
[INFO] [stdout]     |
[INFO] [stdout] 147 |     fn b(&self) -> &String {
[INFO] [stdout]     |        ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `a`
[INFO] [stdout]    --> src/bin/ch_4_pinning.rs:143:8
[INFO] [stdout]     |
[INFO] [stdout] 143 |     fn a(&self) -> &str {
[INFO] [stdout]     |        ^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `future` is never read
[INFO] [stdout]   --> src/bin/ch_3_async_blocks.rs:60:13
[INFO] [stdout]    |
[INFO] [stdout] 60 |         let mut future = None;
[INFO] [stdout]    |             ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `foo_expanded`
[INFO] [stdout]   --> src/bin/ch_3_async_blocks.rs:10:4
[INFO] [stdout]    |
[INFO] [stdout] 10 | fn foo_expanded<'a>(x: &'a u8) -> impl Future<Output = u8> + 'a {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `future` is never read
[INFO] [stdout]   --> src/bin/ch_3_async_blocks.rs:60:13
[INFO] [stdout]    |
[INFO] [stdout] 60 |         let mut future = None;
[INFO] [stdout]    |             ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `foo_expanded`
[INFO] [stdout]   --> src/bin/ch_3_async_blocks.rs:10:4
[INFO] [stdout]    |
[INFO] [stdout] 10 | fn foo_expanded<'a>(x: &'a u8) -> impl Future<Output = u8> + 'a {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ThreadPool`
[INFO] [stdout]  --> src/bin/ch_6_select.rs:2:26
[INFO] [stdout]   |
[INFO] [stdout] 2 |     executor::{block_on, ThreadPool, ThreadPoolBuilder},
[INFO] [stdout]   |                          ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `tokio::task`
[INFO] [stdout]  --> src/bin/ch_6_select.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use tokio::task;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `tokio::time::delay_for`
[INFO] [stdout]  --> src/bin/ch_6_select.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use tokio::time::delay_for;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `async_book::delay_future::Delay`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 | use async_book::delay_future::Delay;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `LocalSpawnExt`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:14:21
[INFO] [stdout]    |
[INFO] [stdout] 14 | use futures::task::{LocalSpawnExt, SpawnExt};
[INFO] [stdout]    |                     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread::Thread`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 | use std::thread::Thread;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ThreadPool`
[INFO] [stdout]  --> src/bin/ch_6_select.rs:2:26
[INFO] [stdout]   |
[INFO] [stdout] 2 |     executor::{block_on, ThreadPool, ThreadPoolBuilder},
[INFO] [stdout]   |                          ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `tokio::task`
[INFO] [stdout]  --> src/bin/ch_6_select.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use tokio::task;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `tokio::time::delay_for`
[INFO] [stdout]  --> src/bin/ch_6_select.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use tokio::time::delay_for;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `async_book::delay_future::Delay`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 | use async_book::delay_future::Delay;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `LocalSpawnExt`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:14:21
[INFO] [stdout]    |
[INFO] [stdout] 14 | use futures::task::{LocalSpawnExt, SpawnExt};
[INFO] [stdout]    |                     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread::Thread`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 | use std::thread::Thread;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/bin/ch_6_select.rs:135:9
[INFO] [stdout]     |
[INFO] [stdout] 135 |     let mut pool = ThreadPoolBuilder::new().pool_size(4).create().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: function is never used: `count`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:70:10
[INFO] [stdout]    |
[INFO] [stdout] 70 | async fn count() {
[INFO] [stdout]    |          ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_two_streams`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:94:10
[INFO] [stdout]    |
[INFO] [stdout] 94 | async fn add_two_streams(
[INFO] [stdout]    |          ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `thread_pool_executor`
[INFO] [stdout]    --> src/bin/ch_6_select.rs:134:4
[INFO] [stdout]     |
[INFO] [stdout] 134 | fn thread_pool_executor() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `tokio_runtime`
[INFO] [stdout]    --> src/bin/ch_6_select.rs:146:4
[INFO] [stdout]     |
[INFO] [stdout] 146 | fn tokio_runtime() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/bin/ch_6_select.rs:135:9
[INFO] [stdout]     |
[INFO] [stdout] 135 |     let mut pool = ThreadPoolBuilder::new().pool_size(4).create().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: function is never used: `count`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:70:10
[INFO] [stdout]    |
[INFO] [stdout] 70 | async fn count() {
[INFO] [stdout]    |          ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_two_streams`
[INFO] [stdout]   --> src/bin/ch_6_select.rs:94:10
[INFO] [stdout]    |
[INFO] [stdout] 94 | async fn add_two_streams(
[INFO] [stdout]    |          ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `thread_pool_executor`
[INFO] [stdout]    --> src/bin/ch_6_select.rs:134:4
[INFO] [stdout]     |
[INFO] [stdout] 134 | fn thread_pool_executor() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `tokio_runtime`
[INFO] [stdout]    --> src/bin/ch_6_select.rs:146:4
[INFO] [stdout]     |
[INFO] [stdout] 146 | fn tokio_runtime() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 39.37s
[INFO] running `Command { std: "docker" "inspect" "daa8bb6ae169fa5abd7a4a60d4bd3c75ad5588331bfcb2c88857cd0368b6f8b7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "daa8bb6ae169fa5abd7a4a60d4bd3c75ad5588331bfcb2c88857cd0368b6f8b7", kill_on_drop: false }`
[INFO] [stdout] daa8bb6ae169fa5abd7a4a60d4bd3c75ad5588331bfcb2c88857cd0368b6f8b7