[INFO] cloning repository https://github.com/MichaelGrigoryan25/rust-xo
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/MichaelGrigoryan25/rust-xo" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMichaelGrigoryan25%2Frust-xo", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMichaelGrigoryan25%2Frust-xo'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1a640246e1428882e3fa1a4d35d69e85effca92c
[INFO] checking MichaelGrigoryan25/rust-xo against try#04ea1e1f1a12cfa912c228ca278237d92d0bb6df for pr-148477-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMichaelGrigoryan25%2Frust-xo" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/MichaelGrigoryan25/rust-xo
[INFO] finished tweaking git repo https://github.com/MichaelGrigoryan25/rust-xo
[INFO] tweaked toml for git repo https://github.com/MichaelGrigoryan25/rust-xo written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/MichaelGrigoryan25/rust-xo on toolchain 04ea1e1f1a12cfa912c228ca278237d92d0bb6df
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/MichaelGrigoryan25/rust-xo 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" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rand_chacha v0.3.0
[INFO] [stderr]   Downloaded rand_hc v0.3.0
[INFO] [stderr]   Downloaded rand_core v0.6.2
[INFO] [stderr]   Downloaded libc v0.2.94
[INFO] [stderr]   Downloaded rand v0.8.3
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ad19809befa0df4eea0bbcfc533775603fb5e57bf2d254ab1fd030152c75c948
[INFO] running `Command { std: "docker" "start" "-a" "ad19809befa0df4eea0bbcfc533775603fb5e57bf2d254ab1fd030152c75c948", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ad19809befa0df4eea0bbcfc533775603fb5e57bf2d254ab1fd030152c75c948", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ad19809befa0df4eea0bbcfc533775603fb5e57bf2d254ab1fd030152c75c948", kill_on_drop: false }`
[INFO] [stdout] ad19809befa0df4eea0bbcfc533775603fb5e57bf2d254ab1fd030152c75c948
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e8145da21e347e58011501bfd1009c3113914169d36a4eb5ea9f2884cda6efe8
[INFO] running `Command { std: "docker" "start" "-a" "e8145da21e347e58011501bfd1009c3113914169d36a4eb5ea9f2884cda6efe8", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling getrandom v0.2.2
[INFO] [stderr]     Checking ansi_term v0.12.1
[INFO] [stderr]     Checking rand_core v0.6.2
[INFO] [stderr]     Checking rand_chacha v0.3.0
[INFO] [stderr]     Checking rand v0.8.3
[INFO] [stderr]     Checking rust-xo v1.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[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] 30 |         let _ = &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:52:9
[INFO] [stdout]    |
[INFO] [stdout] 52 |         &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 52 |         let _ = &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:26:13
[INFO] [stdout]    |
[INFO] [stdout] 26 |             &position_string.clear();
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 26 |             let _ = &position_string.clear();
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:40:17
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 &position_string.clear();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 let _ = &position_string.clear();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[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] 30 |         let _ = &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:52:9
[INFO] [stdout]    |
[INFO] [stdout] 52 |         &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 52 |         let _ = &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:26:13
[INFO] [stdout]    |
[INFO] [stdout] 26 |             &position_string.clear();
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 26 |             let _ = &position_string.clear();
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:40:17
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 &position_string.clear();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 let _ = &position_string.clear();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.90s
[INFO] running `Command { std: "docker" "inspect" "e8145da21e347e58011501bfd1009c3113914169d36a4eb5ea9f2884cda6efe8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e8145da21e347e58011501bfd1009c3113914169d36a4eb5ea9f2884cda6efe8", kill_on_drop: false }`
[INFO] [stdout] e8145da21e347e58011501bfd1009c3113914169d36a4eb5ea9f2884cda6efe8