[INFO] cloning repository https://github.com/kk3399/rust-basics
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kk3399/rust-basics" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkk3399%2Frust-basics", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkk3399%2Frust-basics'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] eae73eaca33d04df69ed45126bcb9fc6a55ed701
[INFO] checking kk3399/rust-basics against master#3aedcf06b73fc36feeebca3d579e1d2a6c40acc5 for pr-65819
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkk3399%2Frust-basics" "/workspace/builds/worker-9/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kk3399/rust-basics on toolchain 3aedcf06b73fc36feeebca3d579e1d2a6c40acc5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/kk3399/rust-basics
[INFO] finished tweaking git repo https://github.com/kk3399/rust-basics
[INFO] tweaked toml for git repo https://github.com/kk3399/rust-basics written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/kk3399/rust-basics already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "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" "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" "rustops/crates-build-env@sha256:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2af19b2f380b9096da5e2e48f99bdb67f572f3b674782b7d810eaadc0ca917ee
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "2af19b2f380b9096da5e2e48f99bdb67f572f3b674782b7d810eaadc0ca917ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2af19b2f380b9096da5e2e48f99bdb67f572f3b674782b7d810eaadc0ca917ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2af19b2f380b9096da5e2e48f99bdb67f572f3b674782b7d810eaadc0ca917ee", kill_on_drop: false }`
[INFO] [stdout] 2af19b2f380b9096da5e2e48f99bdb67f572f3b674782b7d810eaadc0ca917ee
[INFO] running `Command { std: "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" "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" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c2a10d889b564f4dabee2df84e35483f1e06e34d81d2c38e82e1d5e5bdf7badf
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "c2a10d889b564f4dabee2df84e35483f1e06e34d81d2c38e82e1d5e5bdf7badf", kill_on_drop: false }`
[INFO] [stderr]     Checking rust-basics v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/guess_game.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         io::stdout().flush();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/guess_game.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |         io::stdout().flush();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.38s
[INFO] running `Command { std: "docker" "inspect" "c2a10d889b564f4dabee2df84e35483f1e06e34d81d2c38e82e1d5e5bdf7badf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c2a10d889b564f4dabee2df84e35483f1e06e34d81d2c38e82e1d5e5bdf7badf", kill_on_drop: false }`
[INFO] [stdout] c2a10d889b564f4dabee2df84e35483f1e06e34d81d2c38e82e1d5e5bdf7badf