[INFO] updating cached repository https://github.com/ddefrenne/battleship
[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] a80a793b47a6039c462dba8e442ae1ea489828d8
[INFO] checking ddefrenne/battleship against try#1a608893c03d7722effeb0058e82770bd36b4b3c for pr-66504-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fddefrenne%2Fbattleship" "/workspace/builds/worker-4/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ddefrenne/battleship on toolchain 1a608893c03d7722effeb0058e82770bd36b4b3c
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/ddefrenne/battleship
[INFO] finished tweaking git repo https://github.com/ddefrenne/battleship
[INFO] tweaked toml for git repo https://github.com/ddefrenne/battleship written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/ddefrenne/battleship already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "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] 81364b167ab24e6f2c6e6737b6e57c5a482b2ba15a414157f39c507de02d36a7
[INFO] running `"docker" "start" "-a" "81364b167ab24e6f2c6e6737b6e57c5a482b2ba15a414157f39c507de02d36a7"`
[INFO] [stderr]     Checking battleship v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unnecessary parentheses around `for` head expression
[INFO] [stderr]   --> src/main.rs:19:19
[INFO] [stderr]    |
[INFO] [stderr] 19 |     for column in (1..amount_of_columns + 1) {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `grid`
[INFO] [stderr]  --> src/main.rs:5:9
[INFO] [stderr]   |
[INFO] [stderr] 5 |     let grid = build_grid(&rows, amount_of_columns);
[INFO] [stderr]   |         ^^^^ help: consider prefixing with an underscore: `_grid`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `rows`
[INFO] [stderr]  --> src/main.rs:8:15
[INFO] [stderr]   |
[INFO] [stderr] 8 | fn build_grid(rows: &[char; 10], amount_of_columns: i32) {
[INFO] [stderr]   |               ^^^^ help: consider prefixing with an underscore: `_rows`
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` head expression
[INFO] [stderr]   --> src/main.rs:19:19
[INFO] [stderr]    |
[INFO] [stderr] 19 |     for column in (1..amount_of_columns + 1) {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `grid`
[INFO] [stderr]  --> src/main.rs:5:9
[INFO] [stderr]   |
[INFO] [stderr] 5 |     let grid = build_grid(&rows, amount_of_columns);
[INFO] [stderr]   |         ^^^^ help: consider prefixing with an underscore: `_grid`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `rows`
[INFO] [stderr]  --> src/main.rs:8:15
[INFO] [stderr]   |
[INFO] [stderr] 8 | fn build_grid(rows: &[char; 10], amount_of_columns: i32) {
[INFO] [stderr]   |               ^^^^ help: consider prefixing with an underscore: `_rows`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.40s
[INFO] running `"docker" "inspect" "81364b167ab24e6f2c6e6737b6e57c5a482b2ba15a414157f39c507de02d36a7"`
[INFO] running `"docker" "rm" "-f" "81364b167ab24e6f2c6e6737b6e57c5a482b2ba15a414157f39c507de02d36a7"`
[INFO] [stdout] 81364b167ab24e6f2c6e6737b6e57c5a482b2ba15a414157f39c507de02d36a7