[INFO] cloning repository https://github.com/LiteUnder/learning-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/LiteUnder/learning-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLiteUnder%2Flearning-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLiteUnder%2Flearning-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e78674640c5fcbbb9d090ab694fd270aae9adc20
[INFO] checking LiteUnder/learning-rust/e78674640c5fcbbb9d090ab694fd270aae9adc20 against master#453ceafce32ef8108c604bca5e165ab41d3d6d8c for pr-124187
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLiteUnder%2Flearning-rust" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/LiteUnder/learning-rust on toolchain 453ceafce32ef8108c604bca5e165ab41d3d6d8c
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+453ceafce32ef8108c604bca5e165ab41d3d6d8c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/LiteUnder/learning-rust
[INFO] finished tweaking git repo https://github.com/LiteUnder/learning-rust
[INFO] tweaked toml for git repo https://github.com/LiteUnder/learning-rust written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/LiteUnder/learning-rust 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" "+453ceafce32ef8108c604bca5e165ab41d3d6d8c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:99613afd962a8cfa530ec1899472a458bd015a1ab0af876cf7eb06f6006d81ea" "/opt/rustwide/cargo-home/bin/cargo" "+453ceafce32ef8108c604bca5e165ab41d3d6d8c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 843a957d013a8885ccbfedf9130edc9e1a2cd128bb3276a8c7568de537e0fda8
[INFO] running `Command { std: "docker" "start" "-a" "843a957d013a8885ccbfedf9130edc9e1a2cd128bb3276a8c7568de537e0fda8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "843a957d013a8885ccbfedf9130edc9e1a2cd128bb3276a8c7568de537e0fda8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "843a957d013a8885ccbfedf9130edc9e1a2cd128bb3276a8c7568de537e0fda8", kill_on_drop: false }`
[INFO] [stdout] 843a957d013a8885ccbfedf9130edc9e1a2cd128bb3276a8c7568de537e0fda8
[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@sha256:99613afd962a8cfa530ec1899472a458bd015a1ab0af876cf7eb06f6006d81ea" "/opt/rustwide/cargo-home/bin/cargo" "+453ceafce32ef8108c604bca5e165ab41d3d6d8c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4fc88166dcb84a08a767e0aa03b8ad58ab5da0fa2cbcdddc78a6fdca162e0757
[INFO] running `Command { std: "docker" "start" "-a" "4fc88166dcb84a08a767e0aa03b8ad58ab5da0fa2cbcdddc78a6fdca162e0757", kill_on_drop: false }`
[INFO] [stderr]     Checking testing v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:127:13
[INFO] [stdout]     |
[INFO] [stdout] 127 |         let mut s = String::from("yeah so that happened");
[INFO] [stdout]     |             ----^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:127:13
[INFO] [stdout]     |
[INFO] [stdout] 127 |         let mut s = String::from("yeah so that happened");
[INFO] [stdout]     |             ----^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[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` profile [unoptimized + debuginfo] target(s) in 0.06s
[INFO] running `Command { std: "docker" "inspect" "4fc88166dcb84a08a767e0aa03b8ad58ab5da0fa2cbcdddc78a6fdca162e0757", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4fc88166dcb84a08a767e0aa03b8ad58ab5da0fa2cbcdddc78a6fdca162e0757", kill_on_drop: false }`
[INFO] [stdout] 4fc88166dcb84a08a767e0aa03b8ad58ab5da0fa2cbcdddc78a6fdca162e0757