[INFO] cloning repository https://github.com/mlemesle/word_tree
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mlemesle/word_tree" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmlemesle%2Fword_tree", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmlemesle%2Fword_tree'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] efe72a7e43aac36cc292df8617018c1b1bf22910
[INFO] checking mlemesle/word_tree against master#8007b506ac5da629f223b755f5a5391edd5f6d01 for pr-88041
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmlemesle%2Fword_tree" "/workspace/builds/worker-61/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-61/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mlemesle/word_tree on toolchain 8007b506ac5da629f223b755f5a5391edd5f6d01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mlemesle/word_tree
[INFO] finished tweaking git repo https://github.com/mlemesle/word_tree
[INFO] tweaked toml for git repo https://github.com/mlemesle/word_tree written to /workspace/builds/worker-61/source/Cargo.toml
[INFO] crate git repo https://github.com/mlemesle/word_tree already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "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-61/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-61/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a81dd8288f50d56281636e53210c2df37f6048b13f2715bd2a2071800dfc1131
[INFO] running `Command { std: "docker" "start" "-a" "a81dd8288f50d56281636e53210c2df37f6048b13f2715bd2a2071800dfc1131", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a81dd8288f50d56281636e53210c2df37f6048b13f2715bd2a2071800dfc1131", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a81dd8288f50d56281636e53210c2df37f6048b13f2715bd2a2071800dfc1131", kill_on_drop: false }`
[INFO] [stdout] a81dd8288f50d56281636e53210c2df37f6048b13f2715bd2a2071800dfc1131
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-61/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-61/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+8007b506ac5da629f223b755f5a5391edd5f6d01" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 768775f36e4639bec1379a380e8b9bbc081200b8450fe39984403a25790ed104
[INFO] running `Command { std: "docker" "start" "-a" "768775f36e4639bec1379a380e8b9bbc081200b8450fe39984403a25790ed104", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking word_tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: associated function is never used: `print`
[INFO] [stdout]   --> src/tree/tree.rs:75:12
[INFO] [stdout]    |
[INFO] [stdout] 75 |     pub fn print(self) {
[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: `print`
[INFO] [stdout]   --> src/tree/tree.rs:75:12
[INFO] [stdout]    |
[INFO] [stdout] 75 |     pub fn print(self) {
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/tree/tree.rs:39:17
[INFO] [stdout]    |
[INFO] [stdout] 39 |                 &v.to_graph(depth+1);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 39 |                 let _ = &v.to_graph(depth+1);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/tree/tree.rs:82:13
[INFO] [stdout]    |
[INFO] [stdout] 82 |             &v.generate_labels(0);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 82 |             let _ = &v.generate_labels(0);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/tree/tree.rs:39:17
[INFO] [stdout]    |
[INFO] [stdout] 39 |                 &v.to_graph(depth+1);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 39 |                 let _ = &v.to_graph(depth+1);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/tree/tree.rs:82:13
[INFO] [stdout]    |
[INFO] [stdout] 82 |             &v.generate_labels(0);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 82 |             let _ = &v.generate_labels(0);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 7.92s
[INFO] running `Command { std: "docker" "inspect" "768775f36e4639bec1379a380e8b9bbc081200b8450fe39984403a25790ed104", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "768775f36e4639bec1379a380e8b9bbc081200b8450fe39984403a25790ed104", kill_on_drop: false }`
[INFO] [stdout] 768775f36e4639bec1379a380e8b9bbc081200b8450fe39984403a25790ed104