[INFO] cloning repository https://github.com/rahulnakre/rust_channels
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rahulnakre/rust_channels" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frahulnakre%2Frust_channels", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frahulnakre%2Frust_channels'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 921033a1bacb4b2aee1342b0572b9dace0481830
[INFO] checking rahulnakre/rust_channels against master#c3def263a44e07e09ae6d57abfc8650227fb4972 for pr-118833
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frahulnakre%2Frust_channels" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rahulnakre/rust_channels on toolchain c3def263a44e07e09ae6d57abfc8650227fb4972
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c3def263a44e07e09ae6d57abfc8650227fb4972" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/rahulnakre/rust_channels
[INFO] finished tweaking git repo https://github.com/rahulnakre/rust_channels
[INFO] tweaked toml for git repo https://github.com/rahulnakre/rust_channels written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/rahulnakre/rust_channels 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" "+c3def263a44e07e09ae6d57abfc8650227fb4972" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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 rahulnakre/rust_channels against try#29596578cb5035fa2b7ac7fbdfea23fab38836e7 for pr-118833
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frahulnakre%2Frust_channels" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rahulnakre/rust_channels on toolchain 29596578cb5035fa2b7ac7fbdfea23fab38836e7
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+29596578cb5035fa2b7ac7fbdfea23fab38836e7" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/rahulnakre/rust_channels
[INFO] finished tweaking git repo https://github.com/rahulnakre/rust_channels
[INFO] tweaked toml for git repo https://github.com/rahulnakre/rust_channels written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/rahulnakre/rust_channels 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" "+29596578cb5035fa2b7ac7fbdfea23fab38836e7" "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
[INFO] checking rahulnakre/rust_channels against try#29596578cb5035fa2b7ac7fbdfea23fab38836e7 for pr-118833
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frahulnakre%2Frust_channels" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rahulnakre/rust_channels on toolchain 29596578cb5035fa2b7ac7fbdfea23fab38836e7
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+29596578cb5035fa2b7ac7fbdfea23fab38836e7" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/rahulnakre/rust_channels
[INFO] finished tweaking git repo https://github.com/rahulnakre/rust_channels
[INFO] tweaked toml for git repo https://github.com/rahulnakre/rust_channels written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/rahulnakre/rust_channels 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" "+29596578cb5035fa2b7ac7fbdfea23fab38836e7" "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-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+29596578cb5035fa2b7ac7fbdfea23fab38836e7" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 115a24f35481370f9ebb96fd1d9189af5addc9948df686831669c58490ab19a8
[INFO] running `Command { std: "docker" "start" "-a" "115a24f35481370f9ebb96fd1d9189af5addc9948df686831669c58490ab19a8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "115a24f35481370f9ebb96fd1d9189af5addc9948df686831669c58490ab19a8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "115a24f35481370f9ebb96fd1d9189af5addc9948df686831669c58490ab19a8", kill_on_drop: false }`
[INFO] [stdout] 115a24f35481370f9ebb96fd1d9189af5addc9948df686831669c58490ab19a8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+29596578cb5035fa2b7ac7fbdfea23fab38836e7" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a8f8e86125f2de35eb7f3814c4fa209655b8965bba3bfe9da1fb4090f4c16b65
[INFO] running `Command { std: "docker" "start" "-a" "a8f8e86125f2de35eb7f3814c4fa209655b8965bba3bfe9da1fb4090f4c16b65", kill_on_drop: false }`
[INFO] [stderr]     Checking rust_channel_from_stdlib v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::thread`
[INFO] [stdout]  --> src/lib.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::thread;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::sync::mpsc`
[INFO] [stdout]  --> src/lib.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::sync::mpsc;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `rx`
[INFO] [stdout]    --> src/lib.rs:203:22
[INFO] [stdout]     |
[INFO] [stdout] 203 |     let (mut tx, mut rx) = channel();
[INFO] [stdout]     |                      ^^ help: if this is intentional, prefix it with an underscore: `_rx`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:203:18
[INFO] [stdout]     |
[INFO] [stdout] 203 |     let (mut tx, mut rx) = channel();
[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 variable: `rx`
[INFO] [stdout]    --> src/lib.rs:216:14
[INFO] [stdout]     |
[INFO] [stdout] 216 |     let (tx, rx) = mpsc::channel();
[INFO] [stdout]     |              ^^ help: if this is intentional, prefix it with an underscore: `_rx`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/lib.rs:217:5
[INFO] [stdout]     |
[INFO] [stdout] 217 |     tx.send(10);
[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] 217 |     let _ = tx.send(10);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.10s
[INFO] running `Command { std: "docker" "inspect" "a8f8e86125f2de35eb7f3814c4fa209655b8965bba3bfe9da1fb4090f4c16b65", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a8f8e86125f2de35eb7f3814c4fa209655b8965bba3bfe9da1fb4090f4c16b65", kill_on_drop: false }`
[INFO] [stdout] a8f8e86125f2de35eb7f3814c4fa209655b8965bba3bfe9da1fb4090f4c16b65