[INFO] cloning repository https://github.com/beaknit/rust-channels-in-10-commits
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/beaknit/rust-channels-in-10-commits" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbeaknit%2Frust-channels-in-10-commits", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbeaknit%2Frust-channels-in-10-commits'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 644f7eb9c44990dbaeacab2b8ad41c4a673b3856
[INFO] checking beaknit/rust-channels-in-10-commits against master#e23ae72ac7a393961886ea62df065ebb6def7d51 for pr-126571
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbeaknit%2Frust-channels-in-10-commits" "/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/beaknit/rust-channels-in-10-commits on toolchain e23ae72ac7a393961886ea62df065ebb6def7d51
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+e23ae72ac7a393961886ea62df065ebb6def7d51" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/beaknit/rust-channels-in-10-commits
[INFO] finished tweaking git repo https://github.com/beaknit/rust-channels-in-10-commits
[INFO] tweaked toml for git repo https://github.com/beaknit/rust-channels-in-10-commits written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/beaknit/rust-channels-in-10-commits 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" "+e23ae72ac7a393961886ea62df065ebb6def7d51" "fetch" "--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
[ERROR] error running command: no output for 300 seconds
[ERROR] this task or one of its parent failed!
[ERROR] no output for 300 seconds
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.
[INFO] checking beaknit/rust-channels-in-10-commits against try#397f8958d101b259f6baaf92d107d770c95c3ce0 for pr-126571
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbeaknit%2Frust-channels-in-10-commits" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/beaknit/rust-channels-in-10-commits on toolchain 397f8958d101b259f6baaf92d107d770c95c3ce0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+397f8958d101b259f6baaf92d107d770c95c3ce0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/beaknit/rust-channels-in-10-commits
[INFO] finished tweaking git repo https://github.com/beaknit/rust-channels-in-10-commits
[INFO] tweaked toml for git repo https://github.com/beaknit/rust-channels-in-10-commits written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/beaknit/rust-channels-in-10-commits 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" "+397f8958d101b259f6baaf92d107d770c95c3ce0" "fetch" "--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-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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:dff56e7819e73ed36160586b3445e93eb0be776c16704aeeded9c3fb668b2384" "/opt/rustwide/cargo-home/bin/cargo" "+397f8958d101b259f6baaf92d107d770c95c3ce0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 468deb69be3037897e3380b7854205830e102336d0545a48e3ab5ec24e7d2955
[INFO] running `Command { std: "docker" "start" "-a" "468deb69be3037897e3380b7854205830e102336d0545a48e3ab5ec24e7d2955", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "468deb69be3037897e3380b7854205830e102336d0545a48e3ab5ec24e7d2955", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "468deb69be3037897e3380b7854205830e102336d0545a48e3ab5ec24e7d2955", kill_on_drop: false }`
[INFO] [stdout] 468deb69be3037897e3380b7854205830e102336d0545a48e3ab5ec24e7d2955
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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:dff56e7819e73ed36160586b3445e93eb0be776c16704aeeded9c3fb668b2384" "/opt/rustwide/cargo-home/bin/cargo" "+397f8958d101b259f6baaf92d107d770c95c3ce0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2b930efa422bb03524ad67214be3d32915725b7c1aa3e482bcc44ccc6d16d16c
[INFO] running `Command { std: "docker" "start" "-a" "2b930efa422bb03524ad67214be3d32915725b7c1aa3e482bcc44ccc6d16d16c", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.107
[INFO] [stderr]    Compiling proc-macro2 v1.0.32
[INFO] [stderr]    Compiling syn v1.0.81
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking smallvec v1.7.0
[INFO] [stderr]     Checking once_cell v1.8.0
[INFO] [stderr]     Checking instant v0.1.12
[INFO] [stderr]    Compiling tokio v1.14.0
[INFO] [stderr]    Compiling quote v1.0.10
[INFO] [stderr]     Checking parking_lot_core v0.8.5
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking signal-hook-registry v1.4.0
[INFO] [stderr]     Checking mio v0.7.14
[INFO] [stderr]     Checking parking_lot v0.11.2
[INFO] [stderr]    Compiling tokio-macros v1.6.0
[INFO] [stderr]     Checking pipeline-talk v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/main.rs:6:14
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let (tx, mut rx) = mpsc::channel(32);
[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:6:14
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let (tx, mut rx) = mpsc::channel(32);
[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: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:43:5
[INFO] [stdout]    |
[INFO] [stdout] 43 |     msg.response_chan.send(format!("Service 1: {}", msg.value));
[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)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 43 |     let _ = msg.response_chan.send(format!("Service 1: {}", msg.value));
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:43:5
[INFO] [stdout]    |
[INFO] [stdout] 43 |     msg.response_chan.send(format!("Service 1: {}", msg.value));
[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)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 43 |     let _ = msg.response_chan.send(format!("Service 1: {}", msg.value));
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     msg.response_chan.send(format!("Service 2: {}", msg.value));
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 48 |     let _ = msg.response_chan.send(format!("Service 2: {}", msg.value));
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     msg.response_chan.send(format!("Service 2: {}", msg.value));
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 48 |     let _ = msg.response_chan.send(format!("Service 2: {}", msg.value));
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 9.79s
[INFO] running `Command { std: "docker" "inspect" "2b930efa422bb03524ad67214be3d32915725b7c1aa3e482bcc44ccc6d16d16c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2b930efa422bb03524ad67214be3d32915725b7c1aa3e482bcc44ccc6d16d16c", kill_on_drop: false }`
[INFO] [stdout] 2b930efa422bb03524ad67214be3d32915725b7c1aa3e482bcc44ccc6d16d16c