[INFO] cloning repository https://github.com/PhilipDaniels/word_chains
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/PhilipDaniels/word_chains" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPhilipDaniels%2Fword_chains", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPhilipDaniels%2Fword_chains'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] bf9430e6e6619f1988c7fe4bd4d6af853559eb35
[INFO] checking PhilipDaniels/word_chains against beta for pr-78714
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FPhilipDaniels%2Fword_chains" "/workspace/builds/worker-11/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-11/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/PhilipDaniels/word_chains on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/PhilipDaniels/word_chains
[INFO] finished tweaking git repo https://github.com/PhilipDaniels/word_chains
[INFO] tweaked toml for git repo https://github.com/PhilipDaniels/word_chains written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate git repo https://github.com/PhilipDaniels/word_chains already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] dd6d8b5c15403cc75cdedda1dabfea6a0df3976dba8832c3d63b03f9c0ff6ded
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "dd6d8b5c15403cc75cdedda1dabfea6a0df3976dba8832c3d63b03f9c0ff6ded", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dd6d8b5c15403cc75cdedda1dabfea6a0df3976dba8832c3d63b03f9c0ff6ded", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dd6d8b5c15403cc75cdedda1dabfea6a0df3976dba8832c3d63b03f9c0ff6ded", kill_on_drop: false }`
[INFO] [stdout] dd6d8b5c15403cc75cdedda1dabfea6a0df3976dba8832c3d63b03f9c0ff6ded
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 44276c2527c4b24f0c8c0ac41e13162417c0dccb5158a26a340e3e5961487eca
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "44276c2527c4b24f0c8c0ac41e13162417c0dccb5158a26a340e3e5961487eca", kill_on_drop: false }`
[INFO] [stderr]     Checking atty v0.2.8
[INFO] [stderr]    Compiling quote v0.4.2
[INFO] [stderr]     Checking clap v2.31.1
[INFO] [stderr]    Compiling syn v0.12.14
[INFO] [stderr]    Compiling structopt-derive v0.2.5
[INFO] [stderr]     Checking structopt v0.2.5
[INFO] [stderr]     Checking word_chains v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #[macro_use] extern crate structopt;
[INFO] [stdout]   | ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #[macro_use] extern crate structopt;
[INFO] [stdout]   | ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `g`
[INFO] [stdout]   --> src/letter_differences.rs:36:13
[INFO] [stdout]    |
[INFO] [stdout] 36 |         let g = make_graph(&rwords_for_table);
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_g`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `g`
[INFO] [stdout]   --> src/letter_differences.rs:36:13
[INFO] [stdout]    |
[INFO] [stdout] 36 |         let g = make_graph(&rwords_for_table);
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_g`
[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/dictionary.rs:23:13
[INFO] [stdout]    |
[INFO] [stdout] 23 |         let mut rdr = io::BufReader::new(file);
[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/dictionary.rs:23:13
[INFO] [stdout]    |
[INFO] [stdout] 23 |         let mut rdr = io::BufReader::new(file);
[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: field is never read: `word`
[INFO] [stdout]  --> src/graph.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     word: &'word String,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `word`
[INFO] [stdout]   --> src/graph.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 |     fn word(&self) -> &String {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `word`
[INFO] [stdout]  --> src/graph.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     word: &'word String,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `word`
[INFO] [stdout]   --> src/graph.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 |     fn word(&self) -> &String {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 12.13s
[INFO] running `Command { std: "docker" "inspect" "44276c2527c4b24f0c8c0ac41e13162417c0dccb5158a26a340e3e5961487eca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "44276c2527c4b24f0c8c0ac41e13162417c0dccb5158a26a340e3e5961487eca", kill_on_drop: false }`
[INFO] [stdout] 44276c2527c4b24f0c8c0ac41e13162417c0dccb5158a26a340e3e5961487eca