[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 try#9053a8ad740a9e131b53ea98acecf68cf79134fe for pr-137045
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frahulnakre%2Frust_channels" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rahulnakre/rust_channels on toolchain 9053a8ad740a9e131b53ea98acecf68cf79134fe
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+9053a8ad740a9e131b53ea98acecf68cf79134fe" "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-3-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" "+9053a8ad740a9e131b53ea98acecf68cf79134fe" "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#9053a8ad740a9e131b53ea98acecf68cf79134fe for pr-137045
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frahulnakre%2Frust_channels" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rahulnakre/rust_channels on toolchain 9053a8ad740a9e131b53ea98acecf68cf79134fe
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+9053a8ad740a9e131b53ea98acecf68cf79134fe" "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-3-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" "+9053a8ad740a9e131b53ea98acecf68cf79134fe" "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-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+9053a8ad740a9e131b53ea98acecf68cf79134fe" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 473f1e0be72845a05e0f782b4a38aeddfa74df16ae8c6672eab5808fa07f7bf5
[INFO] running `Command { std: "docker" "start" "-a" "473f1e0be72845a05e0f782b4a38aeddfa74df16ae8c6672eab5808fa07f7bf5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "473f1e0be72845a05e0f782b4a38aeddfa74df16ae8c6672eab5808fa07f7bf5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "473f1e0be72845a05e0f782b4a38aeddfa74df16ae8c6672eab5808fa07f7bf5", kill_on_drop: false }`
[INFO] [stdout] 473f1e0be72845a05e0f782b4a38aeddfa74df16ae8c6672eab5808fa07f7bf5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+9053a8ad740a9e131b53ea98acecf68cf79134fe" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ef7c3b17cbba59dff5ddd5b79f0b4838fc27f896f73f7df73c401f1912c0f115
[INFO] running `Command { std: "docker" "start" "-a" "ef7c3b17cbba59dff5ddd5b79f0b4838fc27f896f73f7df73c401f1912c0f115", 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: 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] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.08s
[INFO] running `Command { std: "docker" "inspect" "ef7c3b17cbba59dff5ddd5b79f0b4838fc27f896f73f7df73c401f1912c0f115", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ef7c3b17cbba59dff5ddd5b79f0b4838fc27f896f73f7df73c401f1912c0f115", kill_on_drop: false }`
[INFO] [stdout] ef7c3b17cbba59dff5ddd5b79f0b4838fc27f896f73f7df73c401f1912c0f115