[INFO] cloning repository https://github.com/tomowatt/guessing_game
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/tomowatt/guessing_game" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftomowatt%2Fguessing_game", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftomowatt%2Fguessing_game'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d5ebfa795e8cc7549a6185f8986c8d397b8080c3
[INFO] checking tomowatt/guessing_game against master#642c19bfc3a5c1de985bf5d0cc8207ac9d22708a for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftomowatt%2Fguessing_game" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/tomowatt/guessing_game
[INFO] finished tweaking git repo https://github.com/tomowatt/guessing_game
[INFO] tweaked toml for git repo https://github.com/tomowatt/guessing_game written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/tomowatt/guessing_game on toolchain 642c19bfc3a5c1de985bf5d0cc8207ac9d22708a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/tomowatt/guessing_game 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" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded syn v1.0.69
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] da563cf61cf5f1815b6ad12c11d1491b45947a86aba7eb9fa259aab7be2582dd
[INFO] running `Command { std: "docker" "start" "-a" "da563cf61cf5f1815b6ad12c11d1491b45947a86aba7eb9fa259aab7be2582dd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "da563cf61cf5f1815b6ad12c11d1491b45947a86aba7eb9fa259aab7be2582dd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da563cf61cf5f1815b6ad12c11d1491b45947a86aba7eb9fa259aab7be2582dd", kill_on_drop: false }`
[INFO] [stdout] da563cf61cf5f1815b6ad12c11d1491b45947a86aba7eb9fa259aab7be2582dd
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b582984d177f875fc761e8a034c55c4cd6b42f83e9c3f0bcc2923061fba67c5b
[INFO] running `Command { std: "docker" "start" "-a" "b582984d177f875fc761e8a034c55c4cd6b42f83e9c3f0bcc2923061fba67c5b", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.93
[INFO] [stderr]    Compiling proc-macro2 v1.0.26
[INFO] [stderr]    Compiling getrandom v0.2.2
[INFO] [stderr]    Compiling syn v1.0.69
[INFO] [stderr]    Compiling unicode-segmentation v1.7.1
[INFO] [stderr]    Compiling heck v0.3.2
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking rand_core v0.6.2
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking rand_chacha v0.3.0
[INFO] [stderr]     Checking rand v0.8.3
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling structopt-derive v0.4.14
[INFO] [stderr]     Checking structopt v0.3.21
[INFO] [stderr]     Checking guessing_game v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/utils.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     writeln!(writer, "Playing on: {}", difficulty);
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `Result` may be an `Err` variant, which should be handled
[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] 4 |     let _ = writeln!(writer, "Playing on: {}", difficulty);
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/utils.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     writeln!(writer, "Playing on: {}", difficulty);
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `Result` may be an `Err` variant, which should be handled
[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] 4 |     let _ = writeln!(writer, "Playing on: {}", difficulty);
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 8.26s
[INFO] running `Command { std: "docker" "inspect" "b582984d177f875fc761e8a034c55c4cd6b42f83e9c3f0bcc2923061fba67c5b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b582984d177f875fc761e8a034c55c4cd6b42f83e9c3f0bcc2923061fba67c5b", kill_on_drop: false }`
[INFO] [stdout] b582984d177f875fc761e8a034c55c4cd6b42f83e9c3f0bcc2923061fba67c5b