[INFO] cloning repository https://github.com/grenewode/i3switcher
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/grenewode/i3switcher" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgrenewode%2Fi3switcher", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgrenewode%2Fi3switcher'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c6729586aeabaea1debd2d9f72d7e80e65125046
[INFO] checking grenewode/i3switcher against beta for pr-78714
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgrenewode%2Fi3switcher" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/grenewode/i3switcher on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/grenewode/i3switcher
[INFO] finished tweaking git repo https://github.com/grenewode/i3switcher
[INFO] tweaked toml for git repo https://github.com/grenewode/i3switcher written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/grenewode/i3switcher already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6fe4a09a34c830c018485633eb0469d1b4fc806851db5ae5a57e076101b80d61
[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" "6fe4a09a34c830c018485633eb0469d1b4fc806851db5ae5a57e076101b80d61", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6fe4a09a34c830c018485633eb0469d1b4fc806851db5ae5a57e076101b80d61", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6fe4a09a34c830c018485633eb0469d1b4fc806851db5ae5a57e076101b80d61", kill_on_drop: false }`
[INFO] [stdout] 6fe4a09a34c830c018485633eb0469d1b4fc806851db5ae5a57e076101b80d61
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 6273f12b3db49ce713437d44be7ebae8f1834d80f6c9e17779ce18d7e9bf7c65
[INFO] running `Command { std: "docker" "start" "-a" "6273f12b3db49ce713437d44be7ebae8f1834d80f6c9e17779ce18d7e9bf7c65", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v1.0.75
[INFO] [stderr]     Checking term_size v0.3.0
[INFO] [stderr]     Checking atty v0.2.2
[INFO] [stderr]     Checking textwrap v0.7.0
[INFO] [stderr]     Checking clap v2.26.0
[INFO] [stderr]     Checking serde_json v1.0.26
[INFO] [stderr]     Checking i3ipc v0.8.2
[INFO] [stderr]     Checking i3switcher v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:17:17
[INFO] [stdout]    |
[INFO] [stdout] 17 |             let mut iter = workspaces.iter().rev().skip(workspaces.len() - current_idx);
[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:17:17
[INFO] [stdout]    |
[INFO] [stdout] 17 |             let mut iter = workspaces.iter().rev().skip(workspaces.len() - current_idx);
[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 [unoptimized + debuginfo] target(s) in 16.68s
[INFO] running `Command { std: "docker" "inspect" "6273f12b3db49ce713437d44be7ebae8f1834d80f6c9e17779ce18d7e9bf7c65", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6273f12b3db49ce713437d44be7ebae8f1834d80f6c9e17779ce18d7e9bf7c65", kill_on_drop: false }`
[INFO] [stdout] 6273f12b3db49ce713437d44be7ebae8f1834d80f6c9e17779ce18d7e9bf7c65