[INFO] cloning repository https://github.com/xtbl/rust_hello
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/xtbl/rust_hello" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxtbl%2Frust_hello", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxtbl%2Frust_hello'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 75c9b6aff10b3b0b54b07520ccb1fec6abf9b43b
[INFO] checking xtbl/rust_hello against master#9f432d7b44d5c4ac0ce76fed8315ffac8dcab8f9 for pr-124108
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxtbl%2Frust_hello" "/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/xtbl/rust_hello on toolchain 9f432d7b44d5c4ac0ce76fed8315ffac8dcab8f9
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+9f432d7b44d5c4ac0ce76fed8315ffac8dcab8f9" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/xtbl/rust_hello
[INFO] finished tweaking git repo https://github.com/xtbl/rust_hello
[INFO] tweaked toml for git repo https://github.com/xtbl/rust_hello written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/xtbl/rust_hello 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" "+9f432d7b44d5c4ac0ce76fed8315ffac8dcab8f9" "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 xtbl/rust_hello against try#2e5b7739e5167b731ad5eb628f04a54f932f1fe2 for pr-124108
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxtbl%2Frust_hello" "/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/xtbl/rust_hello on toolchain 2e5b7739e5167b731ad5eb628f04a54f932f1fe2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2e5b7739e5167b731ad5eb628f04a54f932f1fe2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/xtbl/rust_hello
[INFO] finished tweaking git repo https://github.com/xtbl/rust_hello
[INFO] tweaked toml for git repo https://github.com/xtbl/rust_hello written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/xtbl/rust_hello 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" "+2e5b7739e5167b731ad5eb628f04a54f932f1fe2" "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 xtbl/rust_hello against try#2e5b7739e5167b731ad5eb628f04a54f932f1fe2 for pr-124108
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxtbl%2Frust_hello" "/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/xtbl/rust_hello on toolchain 2e5b7739e5167b731ad5eb628f04a54f932f1fe2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2e5b7739e5167b731ad5eb628f04a54f932f1fe2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/xtbl/rust_hello
[INFO] finished tweaking git repo https://github.com/xtbl/rust_hello
[INFO] tweaked toml for git repo https://github.com/xtbl/rust_hello written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/xtbl/rust_hello 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" "+2e5b7739e5167b731ad5eb628f04a54f932f1fe2" "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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded libc v0.2.94
[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@sha256:99613afd962a8cfa530ec1899472a458bd015a1ab0af876cf7eb06f6006d81ea" "/opt/rustwide/cargo-home/bin/cargo" "+2e5b7739e5167b731ad5eb628f04a54f932f1fe2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 55627cb4313ce6aec2035664e77477d9e8e4ddca44e0644aa415291bb3da0c2a
[INFO] running `Command { std: "docker" "start" "-a" "55627cb4313ce6aec2035664e77477d9e8e4ddca44e0644aa415291bb3da0c2a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "55627cb4313ce6aec2035664e77477d9e8e4ddca44e0644aa415291bb3da0c2a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "55627cb4313ce6aec2035664e77477d9e8e4ddca44e0644aa415291bb3da0c2a", kill_on_drop: false }`
[INFO] [stdout] 55627cb4313ce6aec2035664e77477d9e8e4ddca44e0644aa415291bb3da0c2a
[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@sha256:99613afd962a8cfa530ec1899472a458bd015a1ab0af876cf7eb06f6006d81ea" "/opt/rustwide/cargo-home/bin/cargo" "+2e5b7739e5167b731ad5eb628f04a54f932f1fe2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e7a79366068602846466d12e7a63ac60eaee511a854e64b56797fa77b828122c
[INFO] running `Command { std: "docker" "start" "-a" "e7a79366068602846466d12e7a63ac60eaee511a854e64b56797fa77b828122c", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling getrandom v0.2.2
[INFO] [stderr]     Checking rand_core v0.6.2
[INFO] [stderr]     Checking rand_chacha v0.3.0
[INFO] [stderr]     Checking rand v0.8.3
[INFO] [stderr]     Checking hello_world v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::io`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::io`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let mut word_freqs = insert_words(splitted);
[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:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let mut word_freqs = insert_words(splitted);
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.32s
[INFO] running `Command { std: "docker" "inspect" "e7a79366068602846466d12e7a63ac60eaee511a854e64b56797fa77b828122c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e7a79366068602846466d12e7a63ac60eaee511a854e64b56797fa77b828122c", kill_on_drop: false }`
[INFO] [stdout] e7a79366068602846466d12e7a63ac60eaee511a854e64b56797fa77b828122c