[INFO] cloning repository https://github.com/itbaiyang/rust-book
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/itbaiyang/rust-book" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fitbaiyang%2Frust-book", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fitbaiyang%2Frust-book'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d30d219e0e460fdcabbf62517b3aba374ef2dfd0
[INFO] testing itbaiyang/rust-book against 1.59.0 for beta-1.60-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fitbaiyang%2Frust-book" "/workspace/builds/worker-1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/itbaiyang/rust-book on toolchain 1.59.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/itbaiyang/rust-book
[INFO] finished tweaking git repo https://github.com/itbaiyang/rust-book
[INFO] tweaked toml for git repo https://github.com/itbaiyang/rust-book written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/itbaiyang/rust-book already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "fetch" "--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-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0f082ab6685329004731494a10f4dcd8227ddf5738a4a304411d37b240033709
[INFO] running `Command { std: "docker" "start" "-a" "0f082ab6685329004731494a10f4dcd8227ddf5738a4a304411d37b240033709", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0f082ab6685329004731494a10f4dcd8227ddf5738a4a304411d37b240033709", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0f082ab6685329004731494a10f4dcd8227ddf5738a4a304411d37b240033709", kill_on_drop: false }`
[INFO] [stdout] 0f082ab6685329004731494a10f4dcd8227ddf5738a4a304411d37b240033709
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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=warn" "-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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 779355d3de477b1baf2859bd2aafebf6f379cae8d5d1c2798a6395f5be681781
[INFO] running `Command { std: "docker" "start" "-a" "779355d3de477b1baf2859bd2aafebf6f379cae8d5d1c2798a6395f5be681781", kill_on_drop: false }`
[INFO] [stderr]    Compiling book v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `id`
[INFO] [stdout]  --> src/struct_m/struct_test.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     id: i32,
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `is_good`
[INFO] [stdout]  --> src/struct_m/struct_test.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     is_good: bool
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> src/t_m/t_test.rs:37:5
[INFO] [stdout]    |
[INFO] [stdout] 37 |     y: U,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]  --> src/ref_m/tree_list.rs:8:3
[INFO] [stdout]   |
[INFO] [stdout] 8 |   value: i32,
[INFO] [stdout]   |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `children`
[INFO] [stdout]   --> src/ref_m/tree_list.rs:10:3
[INFO] [stdout]    |
[INFO] [stdout] 10 |   children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `width`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:39:3
[INFO] [stdout]    |
[INFO] [stdout] 39 |   width: u32,
[INFO] [stdout]    |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `height`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:40:3
[INFO] [stdout]    |
[INFO] [stdout] 40 |   height: u32,
[INFO] [stdout]    |   ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `label`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:41:3
[INFO] [stdout]    |
[INFO] [stdout] 41 |   label: String,
[INFO] [stdout]    |   ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `width`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:51:3
[INFO] [stdout]    |
[INFO] [stdout] 51 |   width: u32,
[INFO] [stdout]    |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `height`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:52:3
[INFO] [stdout]    |
[INFO] [stdout] 52 |   height: u32,
[INFO] [stdout]    |   ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `options`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:53:3
[INFO] [stdout]    |
[INFO] [stdout] 53 |   options: Vec<String>,
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `split_at_mut`
[INFO] [stdout]   --> src/advanced_m/unsafe_init.rs:58:4
[INFO] [stdout]    |
[INFO] [stdout] 58 | fn split_at_mut(slice: &mut [i32], mid: usize) -> (&mut [i32], &mut [i32]) {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.98s
[INFO] running `Command { std: "docker" "inspect" "779355d3de477b1baf2859bd2aafebf6f379cae8d5d1c2798a6395f5be681781", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "779355d3de477b1baf2859bd2aafebf6f379cae8d5d1c2798a6395f5be681781", kill_on_drop: false }`
[INFO] [stdout] 779355d3de477b1baf2859bd2aafebf6f379cae8d5d1c2798a6395f5be681781
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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=warn" "-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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4ec702bb702df0ae29be7de8853c369f9f697f215c13e813947bfadebb1596c9
[INFO] running `Command { std: "docker" "start" "-a" "4ec702bb702df0ae29be7de8853c369f9f697f215c13e813947bfadebb1596c9", kill_on_drop: false }`
[INFO] [stdout] warning: field is never read: `id`
[INFO] [stdout]  --> src/struct_m/struct_test.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     id: i32,
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `is_good`
[INFO] [stdout]  --> src/struct_m/struct_test.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     is_good: bool
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> src/t_m/t_test.rs:37:5
[INFO] [stdout]    |
[INFO] [stdout] 37 |     y: U,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]  --> src/ref_m/tree_list.rs:8:3
[INFO] [stdout]   |
[INFO] [stdout] 8 |   value: i32,
[INFO] [stdout]   |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `children`
[INFO] [stdout]   --> src/ref_m/tree_list.rs:10:3
[INFO] [stdout]    |
[INFO] [stdout] 10 |   children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `width`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:39:3
[INFO] [stdout]    |
[INFO] [stdout] 39 |   width: u32,
[INFO] [stdout]    |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `height`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:40:3
[INFO] [stdout]    |
[INFO] [stdout] 40 |   height: u32,
[INFO] [stdout]    |   ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `label`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:41:3
[INFO] [stdout]    |
[INFO] [stdout] 41 |   label: String,
[INFO] [stdout]    |   ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `width`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:51:3
[INFO] [stdout]    |
[INFO] [stdout] 51 |   width: u32,
[INFO] [stdout]    |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling book v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `height`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:52:3
[INFO] [stdout]    |
[INFO] [stdout] 52 |   height: u32,
[INFO] [stdout]    |   ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `options`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:53:3
[INFO] [stdout]    |
[INFO] [stdout] 53 |   options: Vec<String>,
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `split_at_mut`
[INFO] [stdout]   --> src/advanced_m/unsafe_init.rs:58:4
[INFO] [stdout]    |
[INFO] [stdout] 58 | fn split_at_mut(slice: &mut [i32], mid: usize) -> (&mut [i32], &mut [i32]) {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `id`
[INFO] [stdout]  --> src/struct_m/struct_test.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     id: i32,
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `is_good`
[INFO] [stdout]  --> src/struct_m/struct_test.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     is_good: bool
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `y`
[INFO] [stdout]   --> src/t_m/t_test.rs:37:5
[INFO] [stdout]    |
[INFO] [stdout] 37 |     y: U,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]  --> src/ref_m/tree_list.rs:8:3
[INFO] [stdout]   |
[INFO] [stdout] 8 |   value: i32,
[INFO] [stdout]   |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `children`
[INFO] [stdout]   --> src/ref_m/tree_list.rs:10:3
[INFO] [stdout]    |
[INFO] [stdout] 10 |   children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `width`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:39:3
[INFO] [stdout]    |
[INFO] [stdout] 39 |   width: u32,
[INFO] [stdout]    |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `height`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:40:3
[INFO] [stdout]    |
[INFO] [stdout] 40 |   height: u32,
[INFO] [stdout]    |   ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `label`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:41:3
[INFO] [stdout]    |
[INFO] [stdout] 41 |   label: String,
[INFO] [stdout]    |   ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `width`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:51:3
[INFO] [stdout]    |
[INFO] [stdout] 51 |   width: u32,
[INFO] [stdout]    |   ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `height`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:52:3
[INFO] [stdout]    |
[INFO] [stdout] 52 |   height: u32,
[INFO] [stdout]    |   ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `options`
[INFO] [stdout]   --> src/oop_m/oop_trait.rs:53:3
[INFO] [stdout]    |
[INFO] [stdout] 53 |   options: Vec<String>,
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `split_at_mut`
[INFO] [stdout]   --> src/advanced_m/unsafe_init.rs:58:4
[INFO] [stdout]    |
[INFO] [stdout] 58 | fn split_at_mut(slice: &mut [i32], mid: usize) -> (&mut [i32], &mut [i32]) {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.45s
[INFO] running `Command { std: "docker" "inspect" "4ec702bb702df0ae29be7de8853c369f9f697f215c13e813947bfadebb1596c9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4ec702bb702df0ae29be7de8853c369f9f697f215c13e813947bfadebb1596c9", kill_on_drop: false }`
[INFO] [stdout] 4ec702bb702df0ae29be7de8853c369f9f697f215c13e813947bfadebb1596c9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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=warn" "-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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 463846ced92583cdba7376cd3e31eff29ff115e7d66a0472f42b2bd269bbfaa6
[INFO] running `Command { std: "docker" "start" "-a" "463846ced92583cdba7376cd3e31eff29ff115e7d66a0472f42b2bd269bbfaa6", kill_on_drop: false }`
[INFO] [stderr] warning: field is never read: `id`
[INFO] [stderr]  --> src/struct_m/struct_test.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 |     id: i32,
[INFO] [stderr]   |     ^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `is_good`
[INFO] [stderr]  --> src/struct_m/struct_test.rs:5:5
[INFO] [stderr]   |
[INFO] [stderr] 5 |     is_good: bool
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `y`
[INFO] [stderr]   --> src/t_m/t_test.rs:37:5
[INFO] [stderr]    |
[INFO] [stderr] 37 |     y: U,
[INFO] [stderr]    |     ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `value`
[INFO] [stderr]  --> src/ref_m/tree_list.rs:8:3
[INFO] [stderr]   |
[INFO] [stderr] 8 |   value: i32,
[INFO] [stderr]   |   ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `children`
[INFO] [stderr]   --> src/ref_m/tree_list.rs:10:3
[INFO] [stderr]    |
[INFO] [stderr] 10 |   children: RefCell<Vec<Rc<Node>>>,
[INFO] [stderr]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `width`
[INFO] [stderr]   --> src/oop_m/oop_trait.rs:39:3
[INFO] [stderr]    |
[INFO] [stderr] 39 |   width: u32,
[INFO] [stderr]    |   ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `height`
[INFO] [stderr]   --> src/oop_m/oop_trait.rs:40:3
[INFO] [stderr]    |
[INFO] [stderr] 40 |   height: u32,
[INFO] [stderr]    |   ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `label`
[INFO] [stderr]   --> src/oop_m/oop_trait.rs:41:3
[INFO] [stderr]    |
[INFO] [stderr] 41 |   label: String,
[INFO] [stderr]    |   ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `width`
[INFO] [stderr]   --> src/oop_m/oop_trait.rs:51:3
[INFO] [stderr]    |
[INFO] [stderr] 51 |   width: u32,
[INFO] [stderr]    |   ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `height`
[INFO] [stderr]   --> src/oop_m/oop_trait.rs:52:3
[INFO] [stderr]    |
[INFO] [stderr] 52 |   height: u32,
[INFO] [stderr]    |   ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `options`
[INFO] [stderr]   --> src/oop_m/oop_trait.rs:53:3
[INFO] [stderr]    |
[INFO] [stderr] 53 |   options: Vec<String>,
[INFO] [stderr]    |   ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `split_at_mut`
[INFO] [stderr]   --> src/advanced_m/unsafe_init.rs:58:4
[INFO] [stderr]    |
[INFO] [stderr] 58 | fn split_at_mut(slice: &mut [i32], mid: usize) -> (&mut [i32], &mut [i32]) {
[INFO] [stderr]    |    ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `book` (lib) generated 12 warnings
[INFO] [stderr] warning: `book` (lib test) generated 12 warnings (12 duplicates)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.00s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/book-98ab96ee5281198e)
[INFO] [stdout] 
[INFO] [stdout] running 3 tests
[INFO] [stdout] test closures_m::closures_test::call_with_different_values ... ok
[INFO] [stdout] test iter_m::iter_test::lazy_iter ... ok
[INFO] [stdout] test iter_m::iter_test::name ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 3 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/book-106a879fa65c491b)
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]      Running tests/closures_test.rs (/opt/rustwide/target/debug/deps/closures_test-a43642050c35990d)
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test c_test ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 2.00s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests book
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "463846ced92583cdba7376cd3e31eff29ff115e7d66a0472f42b2bd269bbfaa6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "463846ced92583cdba7376cd3e31eff29ff115e7d66a0472f42b2bd269bbfaa6", kill_on_drop: false }`
[INFO] [stdout] 463846ced92583cdba7376cd3e31eff29ff115e7d66a0472f42b2bd269bbfaa6