[INFO] cloning repository https://github.com/kvsari/dicey-dice
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kvsari/dicey-dice" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkvsari%2Fdicey-dice", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkvsari%2Fdicey-dice'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 83f1ac233567bc28ff5cba6b4ab781d4cf2b3cd8
[INFO] checking kvsari/dicey-dice against master#c0bb140a37c81cf59a0b40c21c9413059644e294 for pr-129249-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkvsari%2Fdicey-dice" "/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/kvsari/dicey-dice
[INFO] finished tweaking git repo https://github.com/kvsari/dicey-dice
[INFO] tweaked toml for git repo https://github.com/kvsari/dicey-dice written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/kvsari/dicey-dice on toolchain c0bb140a37c81cf59a0b40c21c9413059644e294
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c0bb140a37c81cf59a0b40c21c9413059644e294" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/kvsari/dicey-dice 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" "+c0bb140a37c81cf59a0b40c21c9413059644e294" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: Cargo.toml: `edition` is set on library `dicey_dice` which is deprecated
[INFO] [stderr] warning: Cargo.toml: `edition` is set on binary `dicey-dice-console` which is deprecated
[INFO] [stderr] warning: `dicey-dice` (manifest) generated 2 warnings
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded wasm-bindgen-shared v0.2.39
[INFO] [stderr]   Downloaded wasm-bindgen-macro-support v0.2.39
[INFO] [stderr]   Downloaded wasm-bindgen-backend v0.2.39
[INFO] [stderr]   Downloaded wasm-bindgen-macro v0.2.39
[INFO] [stderr]   Downloaded derive-getters v0.0.7
[INFO] [stderr]   Downloaded proc-macro2 v0.3.8
[INFO] [stderr]   Downloaded syn v0.15.29
[INFO] [stderr]   Downloaded syn v0.13.11
[INFO] [stderr]   Downloaded quote v0.5.2
[INFO] [stderr]   Downloaded bumpalo v2.2.0
[INFO] [stderr]   Downloaded wasm-bindgen v0.2.39
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:3e793bdf10248eb2ddbd6b0faebed8155c11b4589982e2893733958d93e8d540" "sleep" "infinity", kill_on_drop: false }`
[INFO] [stdout] 424f0896383bb46171919739cdb11619957d4a7f0350902e19b07a215bd4bfb9
[INFO] running `Command { std: "docker" "start" "424f0896383bb46171919739cdb11619957d4a7f0350902e19b07a215bd4bfb9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "424f0896383bb46171919739cdb11619957d4a7f0350902e19b07a215bd4bfb9" "/opt/rustwide/cargo-home/bin/cargo" "+c0bb140a37c81cf59a0b40c21c9413059644e294" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "424f0896383bb46171919739cdb11619957d4a7f0350902e19b07a215bd4bfb9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "424f0896383bb46171919739cdb11619957d4a7f0350902e19b07a215bd4bfb9" "/opt/rustwide/cargo-home/bin/cargo" "+c0bb140a37c81cf59a0b40c21c9413059644e294" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] warning: Cargo.toml: `edition` is set on library `dicey_dice` which is deprecated
[INFO] [stderr] warning: Cargo.toml: `edition` is set on binary `dicey-dice-console` which is deprecated
[INFO] [stderr] warning: `dicey-dice` (manifest) generated 2 warnings
[INFO] [stderr]    Compiling autocfg v0.1.2
[INFO] [stderr]     Checking rand_core v0.4.0
[INFO] [stderr]    Compiling libc v0.2.50
[INFO] [stderr]    Compiling proc-macro2 v0.3.8
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand_jitter v0.1.3
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]    Compiling quote v0.5.2
[INFO] [stderr]    Compiling syn v0.13.11
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]    Compiling derive-getters v0.0.7
[INFO] [stderr]     Checking dicey-dice v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::num::NonZeroUsize`
[INFO] [stdout]  --> src/game/player.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::num::NonZeroUsize;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `model::Hold`
[INFO] [stdout]   --> src/game.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 23 | use model::Hold;
[INFO] [stdout]    |     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::num::NonZeroUsize`
[INFO] [stdout]  --> src/game/player.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::num::NonZeroUsize;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `model::Hold`
[INFO] [stdout]   --> src/game.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 23 | use model::Hold;
[INFO] [stdout]    |     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/hexagon/errors.rs:90:32
[INFO] [stdout]    |
[INFO] [stdout] 90 |     fn cause(&self) -> Option<&error::Error> {
[INFO] [stdout]    |                                ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 90 |     fn cause(&self) -> Option<&dyn error::Error> {
[INFO] [stdout]    |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/hexagon/errors.rs:90:32
[INFO] [stdout]    |
[INFO] [stdout] 90 |     fn cause(&self) -> Option<&error::Error> {
[INFO] [stdout]    |                                ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 90 |     fn cause(&self) -> Option<&dyn error::Error> {
[INFO] [stdout]    |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `empty` is never used
[INFO] [stdout]    --> src/game/model.rs:309:29
[INFO] [stdout]     |
[INFO] [stdout] 304 | impl Tree {
[INFO] [stdout]     | --------- associated function in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 309 |     pub (in crate::game) fn empty(root: Board) -> Self {
[INFO] [stdout]     |                             ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/hexagon/grid.rs:104:13
[INFO] [stdout]     |
[INFO] [stdout] 104 |     fn iter(&self) -> impl Iterator<Item = HexTile<T>> {
[INFO] [stdout]     |             ^^^^^                          ^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |             |
[INFO] [stdout]     |             the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 104 |     fn iter(&self) -> impl Iterator<Item = HexTile<'_, T>> {
[INFO] [stdout]     |                                                    +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `empty` is never used
[INFO] [stdout]    --> src/game/model.rs:309:29
[INFO] [stdout]     |
[INFO] [stdout] 304 | impl Tree {
[INFO] [stdout]     | --------- associated function in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 309 |     pub (in crate::game) fn empty(root: Board) -> Self {
[INFO] [stdout]     |                             ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/hexagon/grid.rs:104:13
[INFO] [stdout]     |
[INFO] [stdout] 104 |     fn iter(&self) -> impl Iterator<Item = HexTile<T>> {
[INFO] [stdout]     |             ^^^^^                          ^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |             |
[INFO] [stdout]     |             the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 104 |     fn iter(&self) -> impl Iterator<Item = HexTile<'_, T>> {
[INFO] [stdout]     |                                                    +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/hexagon/grid.rs:121:17
[INFO] [stdout]     |
[INFO] [stdout] 121 |                 mem::replace(data, new_data);
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 121 |                 let _ = mem::replace(data, new_data);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/hexagon/grid.rs:186:17
[INFO] [stdout]     |
[INFO] [stdout] 186 |     pub fn iter(&self) -> impl Iterator<Item = HexTile<T>> {
[INFO] [stdout]     |                 ^^^^^                          ^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 186 |     pub fn iter(&self) -> impl Iterator<Item = HexTile<'_, T>> {
[INFO] [stdout]     |                                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/hexagon/grid.rs:121:17
[INFO] [stdout]     |
[INFO] [stdout] 121 |                 mem::replace(data, new_data);
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 121 |                 let _ = mem::replace(data, new_data);
[INFO] [stdout]     |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/hexagon/grid.rs:186:17
[INFO] [stdout]     |
[INFO] [stdout] 186 |     pub fn iter(&self) -> impl Iterator<Item = HexTile<T>> {
[INFO] [stdout]     |                 ^^^^^                          ^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 186 |     pub fn iter(&self) -> impl Iterator<Item = HexTile<'_, T>> {
[INFO] [stdout]     |                                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/console.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |             drop(available_choices);
[INFO] [stdout]    |             ^^^^^-----------------^
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  argument has type `&Vec<model::Choice>`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dropping_references)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 75 -             drop(available_choices);
[INFO] [stdout] 75 +             let _ = available_choices;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/console.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |             drop(available_choices);
[INFO] [stdout]    |             ^^^^^-----------------^
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  argument has type `&Vec<model::Choice>`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dropping_references)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 75 -             drop(available_choices);
[INFO] [stdout] 75 +             let _ = available_choices;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::num::NonZeroU8`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::num::NonZeroU8;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::num::NonZeroU8`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::num::NonZeroU8;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `start`
[INFO] [stdout]   --> src/main.rs:15:9
[INFO] [stdout]    |
[INFO] [stdout] 15 |     let start = game::generate_random_board(8, 8, players);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_start`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_player_c`
[INFO] [stdout]   --> src/main.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let ai_player_c = game::Player::new(3, 'C');
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_player_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_player_d`
[INFO] [stdout]   --> src/main.rs:27:9
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let ai_player_d = game::Player::new(4, 'D');
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_player_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_player_e`
[INFO] [stdout]   --> src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let ai_player_e = game::Player::new(5, 'E');
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_player_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_player_f`
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let ai_player_f = game::Player::new(6, 'F');
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_player_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_players`
[INFO] [stdout]   --> src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let ai_players: HashSet<game::Player> = HashSet::from_iter(
[INFO] [stdout]    |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_players`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `start`
[INFO] [stdout]   --> src/main.rs:15:9
[INFO] [stdout]    |
[INFO] [stdout] 15 |     let start = game::generate_random_board(8, 8, players);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_start`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_player_c`
[INFO] [stdout]   --> src/main.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let ai_player_c = game::Player::new(3, 'C');
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_player_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_player_d`
[INFO] [stdout]   --> src/main.rs:27:9
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let ai_player_d = game::Player::new(4, 'D');
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_player_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_player_e`
[INFO] [stdout]   --> src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let ai_player_e = game::Player::new(5, 'E');
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_player_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_player_f`
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let ai_player_f = game::Player::new(6, 'F');
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_player_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ai_players`
[INFO] [stdout]   --> src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let ai_players: HashSet<game::Player> = HashSet::from_iter(
[INFO] [stdout]    |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ai_players`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.74s
[INFO] [stderr] warning: the following packages contain code that will be rejected by a future version of Rust: syn v0.13.11
[INFO] [stderr] note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 2`
[INFO] running `Command { std: "docker" "inspect" "424f0896383bb46171919739cdb11619957d4a7f0350902e19b07a215bd4bfb9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "424f0896383bb46171919739cdb11619957d4a7f0350902e19b07a215bd4bfb9", kill_on_drop: false }`
[INFO] [stdout] 424f0896383bb46171919739cdb11619957d4a7f0350902e19b07a215bd4bfb9
