[INFO] cloning repository https://github.com/dl-watson/rust_islands
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/dl-watson/rust_islands" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdl-watson%2Frust_islands", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdl-watson%2Frust_islands'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 16ae35dd92135f740bc1ee1f40378ce3d339cd87
[INFO] checking dl-watson/rust_islands against try#1f308f12738d8cc40bb23bf0c8114b37c164bb49 for pr-137268
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdl-watson%2Frust_islands" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/dl-watson/rust_islands on toolchain 1f308f12738d8cc40bb23bf0c8114b37c164bb49
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1f308f12738d8cc40bb23bf0c8114b37c164bb49" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/dl-watson/rust_islands
[INFO] finished tweaking git repo https://github.com/dl-watson/rust_islands
[INFO] tweaked toml for git repo https://github.com/dl-watson/rust_islands written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/dl-watson/rust_islands 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" "+1f308f12738d8cc40bb23bf0c8114b37c164bb49" "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
[INFO] checking dl-watson/rust_islands against try#1f308f12738d8cc40bb23bf0c8114b37c164bb49 for pr-137268
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdl-watson%2Frust_islands" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/dl-watson/rust_islands on toolchain 1f308f12738d8cc40bb23bf0c8114b37c164bb49
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1f308f12738d8cc40bb23bf0c8114b37c164bb49" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/dl-watson/rust_islands
[INFO] finished tweaking git repo https://github.com/dl-watson/rust_islands
[INFO] tweaked toml for git repo https://github.com/dl-watson/rust_islands written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/dl-watson/rust_islands 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" "+1f308f12738d8cc40bb23bf0c8114b37c164bb49" "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-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+1f308f12738d8cc40bb23bf0c8114b37c164bb49" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5f5ab32e2b56c26f90f89ad42b457e996e088bec7c02ed74e3f712e152b5f719
[INFO] running `Command { std: "docker" "start" "-a" "5f5ab32e2b56c26f90f89ad42b457e996e088bec7c02ed74e3f712e152b5f719", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5f5ab32e2b56c26f90f89ad42b457e996e088bec7c02ed74e3f712e152b5f719", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5f5ab32e2b56c26f90f89ad42b457e996e088bec7c02ed74e3f712e152b5f719", kill_on_drop: false }`
[INFO] [stdout] 5f5ab32e2b56c26f90f89ad42b457e996e088bec7c02ed74e3f712e152b5f719
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+1f308f12738d8cc40bb23bf0c8114b37c164bb49" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3a5c7de288708995371bcc1dfc4922cec5f86d3566a2bae8f2c1911a8c705cb5
[INFO] running `Command { std: "docker" "start" "-a" "3a5c7de288708995371bcc1dfc4922cec5f86d3566a2bae8f2c1911a8c705cb5", kill_on_drop: false }`
[INFO] [stderr]     Checking islands v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `SafeDisjointSet` is never constructed
[INFO] [stdout]   --> src/disjoint.rs:97:12
[INFO] [stdout]    |
[INFO] [stdout] 97 | pub struct SafeDisjointSet(DisjointSet);
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new` and `find` are never used
[INFO] [stdout]    --> src/disjoint.rs:100:12
[INFO] [stdout]     |
[INFO] [stdout] 99  | impl SafeDisjointSet {
[INFO] [stdout]     | -------------------- associated items in this implementation
[INFO] [stdout] 100 |     pub fn new(size: usize) -> Self {
[INFO] [stdout]     |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 104 |     pub fn find(&self, key: i32) -> Option<i32> {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `SafeDisjointSet` is never constructed
[INFO] [stdout]   --> src/disjoint.rs:97:12
[INFO] [stdout]    |
[INFO] [stdout] 97 | pub struct SafeDisjointSet(DisjointSet);
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new` and `find` are never used
[INFO] [stdout]    --> src/disjoint.rs:100:12
[INFO] [stdout]     |
[INFO] [stdout] 99  | impl SafeDisjointSet {
[INFO] [stdout]     | -------------------- associated items in this implementation
[INFO] [stdout] 100 |     pub fn new(size: usize) -> Self {
[INFO] [stdout]     |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 104 |     pub fn find(&self, key: i32) -> Option<i32> {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.08s
[INFO] running `Command { std: "docker" "inspect" "3a5c7de288708995371bcc1dfc4922cec5f86d3566a2bae8f2c1911a8c705cb5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3a5c7de288708995371bcc1dfc4922cec5f86d3566a2bae8f2c1911a8c705cb5", kill_on_drop: false }`
[INFO] [stdout] 3a5c7de288708995371bcc1dfc4922cec5f86d3566a2bae8f2c1911a8c705cb5