[INFO] updating cached repository https://github.com/Cackbone/2048.rs
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 9c58e9f2ea5fb12a56dd27087d6b618184fc8c6f
[INFO] checking Cackbone/2048.rs against try#e4dba30b9b475d8750370c4dfb49b6541990904d for pr-71393
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCackbone%2F2048.rs" "/workspace/builds/worker-9/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Cackbone/2048.rs on toolchain e4dba30b9b475d8750370c4dfb49b6541990904d
[INFO] running `"/workspace/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/Cackbone/2048.rs
[INFO] finished tweaking git repo https://github.com/Cackbone/2048.rs
[INFO] tweaked toml for git repo https://github.com/Cackbone/2048.rs written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/Cackbone/2048.rs already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] acad6b33c6fd1c2bec786ecb5f470c8a4a37cfc33a008b6c5856555740cd545d
[INFO] running `"docker" "start" "-a" "acad6b33c6fd1c2bec786ecb5f470c8a4a37cfc33a008b6c5856555740cd545d"`
[INFO] [stderr]     Checking libc v0.2.31
[INFO] [stderr]     Checking rand v0.3.16
[INFO] [stderr]     Checking rust_2048 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unnecessary trailing semicolon
[INFO] [stderr]    --> src/main.rs:189:25
[INFO] [stderr]     |
[INFO] [stderr] 189 |         print_line('-');;
[INFO] [stderr]     |                         ^ help: remove this semicolon
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(redundant_semicolons)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary trailing semicolon
[INFO] [stderr]    --> src/main.rs:189:25
[INFO] [stderr]     |
[INFO] [stderr] 189 |         print_line('-');;
[INFO] [stderr]     |                         ^ help: remove this semicolon
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(redundant_semicolons)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `grid_bis` is never read
[INFO] [stderr]   --> src/main.rs:18:9
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let mut grid_bis = [[0i8; 4];4];
[INFO] [stderr]    |         ^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `grid_bis` is never read
[INFO] [stderr]   --> src/main.rs:18:9
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let mut grid_bis = [[0i8; 4];4];
[INFO] [stderr]    |         ^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:97:28
[INFO] [stderr]    |
[INFO] [stderr] 97 | fn move_grid(d: Direction, mut grid: &mut [[i8; 4]; 4])
[INFO] [stderr]    |                            ----^^^^
[INFO] [stderr]    |                            |
[INFO] [stderr]    |                            help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/main.rs:137:13
[INFO] [stderr]     |
[INFO] [stderr] 137 | fn add_tile(mut grid: &mut [[i8; 4]; 4])
[INFO] [stderr]     |             ----^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:52:13
[INFO] [stderr]    |
[INFO] [stderr] 52 |             Command::new("clear").status();
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:75:5
[INFO] [stderr]    |
[INFO] [stderr] 75 |     Command::new("clear").status();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:97:28
[INFO] [stderr]    |
[INFO] [stderr] 97 | fn move_grid(d: Direction, mut grid: &mut [[i8; 4]; 4])
[INFO] [stderr]    |                            ----^^^^
[INFO] [stderr]    |                            |
[INFO] [stderr]    |                            help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/main.rs:137:13
[INFO] [stderr]     |
[INFO] [stderr] 137 | fn add_tile(mut grid: &mut [[i8; 4]; 4])
[INFO] [stderr]     |             ----^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:52:13
[INFO] [stderr]    |
[INFO] [stderr] 52 |             Command::new("clear").status();
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:75:5
[INFO] [stderr]    |
[INFO] [stderr] 75 |     Command::new("clear").status();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.78s
[INFO] running `"docker" "inspect" "acad6b33c6fd1c2bec786ecb5f470c8a4a37cfc33a008b6c5856555740cd545d"`
[INFO] running `"docker" "rm" "-f" "acad6b33c6fd1c2bec786ecb5f470c8a4a37cfc33a008b6c5856555740cd545d"`
[INFO] [stdout] acad6b33c6fd1c2bec786ecb5f470c8a4a37cfc33a008b6c5856555740cd545d