[INFO] cloning repository https://github.com/infoverload/snakegame [INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/infoverload/snakegame" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Finfoverload%2Fsnakegame", kill_on_drop: false }` [INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Finfoverload%2Fsnakegame'... [INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }` [INFO] [stdout] 5b4014a06348ab5a4b3ef1666c754f1bb7cd6bbc [INFO] checking infoverload/snakegame against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Finfoverload%2Fsnakegame" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/infoverload/snakegame on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/infoverload/snakegame [INFO] finished tweaking git repo https://github.com/infoverload/snakegame [INFO] tweaked toml for git repo https://github.com/infoverload/snakegame written to /workspace/builds/worker-4-tc1/source/Cargo.toml [INFO] crate git repo https://github.com/infoverload/snakegame 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Downloading crates ... [INFO] [stderr] Downloaded sdl2-sys v0.30.0 [INFO] [stderr] Downloaded sdl2 v0.30.0 [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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] e59f4b298fded35eea1ce6e091e271841697a5db3f3228971b6d35ac34580960 [INFO] running `Command { std: "docker" "start" "-a" "e59f4b298fded35eea1ce6e091e271841697a5db3f3228971b6d35ac34580960", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "e59f4b298fded35eea1ce6e091e271841697a5db3f3228971b6d35ac34580960", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "e59f4b298fded35eea1ce6e091e271841697a5db3f3228971b6d35ac34580960", kill_on_drop: false }` [INFO] [stdout] e59f4b298fded35eea1ce6e091e271841697a5db3f3228971b6d35ac34580960 [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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }` [INFO] [stdout] ccecb45f7a87ed2ec78f43b04de69ca43c048cbb8b208d60f97094b7d4c1324b [INFO] running `Command { std: "docker" "start" "-a" "ccecb45f7a87ed2ec78f43b04de69ca43c048cbb8b208d60f97094b7d4c1324b", kill_on_drop: false }` [INFO] [stderr] Compiling autocfg v0.1.7 [INFO] [stderr] Compiling libc v0.2.65 [INFO] [stderr] Compiling getrandom v0.1.13 [INFO] [stderr] Checking ppv-lite86 v0.2.6 [INFO] [stderr] Compiling sdl2-sys v0.30.0 [INFO] [stderr] Checking lazy_static v0.2.11 [INFO] [stderr] Checking bitflags v0.7.0 [INFO] [stderr] Compiling num-traits v0.2.10 [INFO] [stderr] Compiling num-integer v0.1.41 [INFO] [stderr] Compiling num-iter v0.1.39 [INFO] [stderr] Checking c2-chacha v0.2.3 [INFO] [stderr] Checking rand v0.4.6 [INFO] [stderr] Checking rand_core v0.5.1 [INFO] [stderr] Checking rand_chacha v0.2.1 [INFO] [stderr] Checking rand v0.7.2 [INFO] [stderr] Checking num v0.1.42 [INFO] [stderr] Checking rand v0.3.23 [INFO] [stderr] Checking sdl2 v0.30.0 [INFO] [stderr] Checking rusty_snake v0.1.0 (/opt/rustwide/workdir) [INFO] [stdout] warning: found module declaration for lib.rs [INFO] [stdout] --> src/main.rs:6:1 [INFO] [stdout] | [INFO] [stdout] 6 | pub mod lib; [INFO] [stdout] | ^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = note: lib.rs is the root of this crate's library target [INFO] [stdout] = help: to refer to it from other targets, use the library's name as the path [INFO] [stdout] = note: `#[warn(special_module_name)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `rand` is imported redundantly [INFO] [stdout] --> src/lib/mod.rs:7:5 [INFO] [stdout] | [INFO] [stdout] 7 | use rand; [INFO] [stdout] | ^^^^ the item `rand` is already defined by prelude [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_imports)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: found module declaration for lib.rs [INFO] [stdout] --> src/main.rs:6:1 [INFO] [stdout] | [INFO] [stdout] 6 | pub mod lib; [INFO] [stdout] | ^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = note: lib.rs is the root of this crate's library target [INFO] [stdout] = help: to refer to it from other targets, use the library's name as the path [INFO] [stdout] = note: `#[warn(special_module_name)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `rand` is imported redundantly [INFO] [stdout] --> src/lib/mod.rs:7:5 [INFO] [stdout] | [INFO] [stdout] 7 | use rand; [INFO] [stdout] | ^^^^ the item `rand` is already defined by prelude [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_imports)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `grid` [INFO] [stdout] --> src/lib/mod.rs:61:9 [INFO] [stdout] | [INFO] [stdout] 61 | let grid = &grid_data.grid; [INFO] [stdout] | ^^^^ help: if this is intentional, prefix it with an underscore: `_grid` [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_variables)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `grid` [INFO] [stdout] --> src/lib/mod.rs:61:9 [INFO] [stdout] | [INFO] [stdout] 61 | let grid = &grid_data.grid; [INFO] [stdout] | ^^^^ help: if this is intentional, prefix it with an underscore: `_grid` [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_variables)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `direction` [INFO] [stdout] --> src/main.rs:22:13 [INFO] [stdout] | [INFO] [stdout] 22 | let mut direction = (1, 0); [INFO] [stdout] | ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_direction` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `direction` [INFO] [stdout] --> src/main.rs:22:13 [INFO] [stdout] | [INFO] [stdout] 22 | let mut direction = (1, 0); [INFO] [stdout] | ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_direction` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: variable does not need to be mutable [INFO] [stdout] --> src/main.rs:21:9 [INFO] [stdout] | [INFO] [stdout] 21 | let mut grid = lib::grid_init(columns, rows); [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/main.rs:22:9 [INFO] [stdout] | [INFO] [stdout] 22 | let mut direction = (1, 0); [INFO] [stdout] | ----^^^^^^^^^ [INFO] [stdout] | | [INFO] [stdout] | help: remove this `mut` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: variable does not need to be mutable [INFO] [stdout] --> src/main.rs:21:9 [INFO] [stdout] | [INFO] [stdout] 21 | let mut grid = lib::grid_init(columns, rows); [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/main.rs:22:9 [INFO] [stdout] | [INFO] [stdout] 22 | let mut direction = (1, 0); [INFO] [stdout] | ----^^^^^^^^^ [INFO] [stdout] | | [INFO] [stdout] | help: remove this `mut` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: 6 warnings emitted [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: 6 warnings emitted [INFO] [stdout] [INFO] [stdout] [INFO] [stderr] Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.67s [INFO] running `Command { std: "docker" "inspect" "ccecb45f7a87ed2ec78f43b04de69ca43c048cbb8b208d60f97094b7d4c1324b", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "ccecb45f7a87ed2ec78f43b04de69ca43c048cbb8b208d60f97094b7d4c1324b", kill_on_drop: false }` [INFO] [stdout] ccecb45f7a87ed2ec78f43b04de69ca43c048cbb8b208d60f97094b7d4c1324b [INFO] checking infoverload/snakegame against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Finfoverload%2Fsnakegame" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/infoverload/snakegame on toolchain 645bb72776a6a56a1a8f52631a44bd082b2ba509 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/infoverload/snakegame [INFO] finished tweaking git repo https://github.com/infoverload/snakegame [INFO] tweaked toml for git repo https://github.com/infoverload/snakegame written to /workspace/builds/worker-4-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/infoverload/snakegame 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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] 0c4e3f3d261ec77bb9a94b8c8f0bc1a6ffbf661d08daed226d4c750d2e184f65 [INFO] running `Command { std: "docker" "start" "-a" "0c4e3f3d261ec77bb9a94b8c8f0bc1a6ffbf661d08daed226d4c750d2e184f65", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "0c4e3f3d261ec77bb9a94b8c8f0bc1a6ffbf661d08daed226d4c750d2e184f65", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "0c4e3f3d261ec77bb9a94b8c8f0bc1a6ffbf661d08daed226d4c750d2e184f65", kill_on_drop: false }` [INFO] [stdout] 0c4e3f3d261ec77bb9a94b8c8f0bc1a6ffbf661d08daed226d4c750d2e184f65 [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }` [INFO] [stdout] 400fc476bcb543be33c79b069a27c412e3a0dc45761cf51dd747dc1aa2f7d9df [INFO] running `Command { std: "docker" "start" "-a" "400fc476bcb543be33c79b069a27c412e3a0dc45761cf51dd747dc1aa2f7d9df", kill_on_drop: false }` [INFO] [stderr] Compiling autocfg v0.1.7 [INFO] [stderr] Compiling libc v0.2.65 [INFO] [stderr] Compiling getrandom v0.1.13 [INFO] [stderr] Checking ppv-lite86 v0.2.6 [INFO] [stderr] Compiling sdl2-sys v0.30.0 [INFO] [stderr] Checking lazy_static v0.2.11 [INFO] [stderr] Checking bitflags v0.7.0 [INFO] [stderr] Compiling num-traits v0.2.10 [INFO] [stderr] Compiling num-integer v0.1.41 [INFO] [stderr] Compiling num-iter v0.1.39 [INFO] [stderr] Checking c2-chacha v0.2.3 [INFO] [stderr] Checking rand v0.4.6 [INFO] [stderr] Checking rand_core v0.5.1 [INFO] [stderr] Checking rand_chacha v0.2.1 [INFO] [stderr] Checking rand v0.7.2 [INFO] [stderr] Checking num v0.1.42 [INFO] [stderr] Checking rand v0.3.23 [INFO] [stderr] Checking sdl2 v0.30.0 [INFO] [stderr] Checking rusty_snake v0.1.0 (/opt/rustwide/workdir) [INFO] [stdout] warning: found module declaration for lib.rs [INFO] [stdout] --> src/main.rs:6:1 [INFO] [stdout] | [INFO] [stdout] 6 | pub mod lib; [INFO] [stdout] | ^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = note: lib.rs is the root of this crate's library target [INFO] [stdout] = help: to refer to it from other targets, use the library's name as the path [INFO] [stdout] = note: `#[warn(special_module_name)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `rand` is imported redundantly [INFO] [stdout] --> src/lib/mod.rs:7:5 [INFO] [stdout] | [INFO] [stdout] 7 | use rand; [INFO] [stdout] | ^^^^ the item `rand` is already defined by prelude [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_imports)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `grid` [INFO] [stdout] --> src/lib/mod.rs:61:9 [INFO] [stdout] | [INFO] [stdout] 61 | let grid = &grid_data.grid; [INFO] [stdout] | ^^^^ help: if this is intentional, prefix it with an underscore: `_grid` [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_variables)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `direction` [INFO] [stdout] --> src/main.rs:22:13 [INFO] [stdout] | [INFO] [stdout] 22 | let mut direction = (1, 0); [INFO] [stdout] | ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_direction` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: variable does not need to be mutable [INFO] [stdout] --> src/main.rs:21:9 [INFO] [stdout] | [INFO] [stdout] 21 | let mut grid = lib::grid_init(columns, rows); [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/main.rs:22:9 [INFO] [stdout] | [INFO] [stdout] 22 | let mut direction = (1, 0); [INFO] [stdout] | ----^^^^^^^^^ [INFO] [stdout] | | [INFO] [stdout] | help: remove this `mut` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: found module declaration for lib.rs [INFO] [stdout] --> src/main.rs:6:1 [INFO] [stdout] | [INFO] [stdout] 6 | pub mod lib; [INFO] [stdout] | ^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = note: lib.rs is the root of this crate's library target [INFO] [stdout] = help: to refer to it from other targets, use the library's name as the path [INFO] [stdout] = note: `#[warn(special_module_name)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `rand` is imported redundantly [INFO] [stdout] --> src/lib/mod.rs:7:5 [INFO] [stdout] | [INFO] [stdout] 7 | use rand; [INFO] [stdout] | ^^^^ the item `rand` is already defined by prelude [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_imports)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: 6 warnings emitted [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `grid` [INFO] [stdout] --> src/lib/mod.rs:61:9 [INFO] [stdout] | [INFO] [stdout] 61 | let grid = &grid_data.grid; [INFO] [stdout] | ^^^^ help: if this is intentional, prefix it with an underscore: `_grid` [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_variables)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `direction` [INFO] [stdout] --> src/main.rs:22:13 [INFO] [stdout] | [INFO] [stdout] 22 | let mut direction = (1, 0); [INFO] [stdout] | ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_direction` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: variable does not need to be mutable [INFO] [stdout] --> src/main.rs:21:9 [INFO] [stdout] | [INFO] [stdout] 21 | let mut grid = lib::grid_init(columns, rows); [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/main.rs:22:9 [INFO] [stdout] | [INFO] [stdout] 22 | let mut direction = (1, 0); [INFO] [stdout] | ----^^^^^^^^^ [INFO] [stdout] | | [INFO] [stdout] | help: remove this `mut` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: 6 warnings emitted [INFO] [stdout] [INFO] [stdout] [INFO] [stderr] Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.92s [INFO] running `Command { std: "docker" "inspect" "400fc476bcb543be33c79b069a27c412e3a0dc45761cf51dd747dc1aa2f7d9df", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "400fc476bcb543be33c79b069a27c412e3a0dc45761cf51dd747dc1aa2f7d9df", kill_on_drop: false }` [INFO] [stdout] 400fc476bcb543be33c79b069a27c412e3a0dc45761cf51dd747dc1aa2f7d9df