[INFO] cloning repository https://github.com/XYC-EXP/rfmt
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/XYC-EXP/rfmt" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FXYC-EXP%2Frfmt", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FXYC-EXP%2Frfmt'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 95c76e9df60e26081f9a17d8c41716632177ec25
[INFO] checking XYC-EXP/rfmt against master#936f2600b6c903b04387f74ed5cbce88bb06d243 for pr-91141
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FXYC-EXP%2Frfmt" "/workspace/builds/worker-104/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-104/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/XYC-EXP/rfmt on toolchain 936f2600b6c903b04387f74ed5cbce88bb06d243
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/XYC-EXP/rfmt
[INFO] finished tweaking git repo https://github.com/XYC-EXP/rfmt
[INFO] tweaked toml for git repo https://github.com/XYC-EXP/rfmt written to /workspace/builds/worker-104/source/Cargo.toml
[INFO] crate git repo https://github.com/XYC-EXP/rfmt already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 54a85432696a7d0ef2588646c8004e88f5d04852d4c69213a4c4dd99335c954f
[INFO] running `Command { std: "docker" "start" "-a" "54a85432696a7d0ef2588646c8004e88f5d04852d4c69213a4c4dd99335c954f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "54a85432696a7d0ef2588646c8004e88f5d04852d4c69213a4c4dd99335c954f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "54a85432696a7d0ef2588646c8004e88f5d04852d4c69213a4c4dd99335c954f", kill_on_drop: false }`
[INFO] [stdout] 54a85432696a7d0ef2588646c8004e88f5d04852d4c69213a4c4dd99335c954f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-104/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 18527499cbd62d1e6c91a55b5fed883ac3d34c3b60dae3ea9d49f20d3a761354
[INFO] running `Command { std: "docker" "start" "-a" "18527499cbd62d1e6c91a55b5fed883ac3d34c3b60dae3ea9d49f20d3a761354", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking rfmt v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/executor.rs:4:6
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let mut output: Vec<String> = Vec::new();
[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/executor.rs:4:6
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let mut output: Vec<String> = Vec::new();
[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: function is never used: `list_files`
[INFO] [stdout]  --> src/executor.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub fn list_files() -> Vec<String> {
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `list_files`
[INFO] [stdout]  --> src/executor.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub fn list_files() -> Vec<String> {
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.04s
[INFO] running `Command { std: "docker" "inspect" "18527499cbd62d1e6c91a55b5fed883ac3d34c3b60dae3ea9d49f20d3a761354", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "18527499cbd62d1e6c91a55b5fed883ac3d34c3b60dae3ea9d49f20d3a761354", kill_on_drop: false }`
[INFO] [stdout] 18527499cbd62d1e6c91a55b5fed883ac3d34c3b60dae3ea9d49f20d3a761354