[INFO] cloning repository https://github.com/haran2001/huffman-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/haran2001/huffman-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fharan2001%2Fhuffman-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fharan2001%2Fhuffman-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cab5084db38090342d243c64b418307d889eda4c
[INFO] checking haran2001/huffman-rust against try#d83b14207998f47b18a34e930157ac0d7c18b16e for pr-149137
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fharan2001%2Fhuffman-rust" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/haran2001/huffman-rust
[INFO] finished tweaking git repo https://github.com/haran2001/huffman-rust
[INFO] tweaked toml for git repo https://github.com/haran2001/huffman-rust written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/haran2001/huffman-rust on toolchain d83b14207998f47b18a34e930157ac0d7c18b16e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d83b14207998f47b18a34e930157ac0d7c18b16e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/haran2001/huffman-rust 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" "+d83b14207998f47b18a34e930157ac0d7c18b16e" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[ERROR] error running command: no output for 300 seconds
[INFO] checking haran2001/huffman-rust against try#d83b14207998f47b18a34e930157ac0d7c18b16e for pr-149137
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fharan2001%2Fhuffman-rust" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/haran2001/huffman-rust
[INFO] finished tweaking git repo https://github.com/haran2001/huffman-rust
[INFO] tweaked toml for git repo https://github.com/haran2001/huffman-rust written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/haran2001/huffman-rust on toolchain d83b14207998f47b18a34e930157ac0d7c18b16e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d83b14207998f47b18a34e930157ac0d7c18b16e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/haran2001/huffman-rust 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" "+d83b14207998f47b18a34e930157ac0d7c18b16e" "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 bitvector v0.1.5
[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@sha256:94a0c148923f5b2b52a63ef0eeb1882ad339ab61bce784c8077cbe41c61feb6c" "/opt/rustwide/cargo-home/bin/cargo" "+d83b14207998f47b18a34e930157ac0d7c18b16e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 25c5ff1a6dd82e19fc0dc46c27a296d80d9ef8e07fa8bd8d28fdb31d2e1e058d
[INFO] running `Command { std: "docker" "start" "-a" "25c5ff1a6dd82e19fc0dc46c27a296d80d9ef8e07fa8bd8d28fdb31d2e1e058d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "25c5ff1a6dd82e19fc0dc46c27a296d80d9ef8e07fa8bd8d28fdb31d2e1e058d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "25c5ff1a6dd82e19fc0dc46c27a296d80d9ef8e07fa8bd8d28fdb31d2e1e058d", kill_on_drop: false }`
[INFO] [stdout] 25c5ff1a6dd82e19fc0dc46c27a296d80d9ef8e07fa8bd8d28fdb31d2e1e058d
[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@sha256:94a0c148923f5b2b52a63ef0eeb1882ad339ab61bce784c8077cbe41c61feb6c" "/opt/rustwide/cargo-home/bin/cargo" "+d83b14207998f47b18a34e930157ac0d7c18b16e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d46e6479c0f53189c573e16abe422e21c2e7d1ba247723db0caa32b08c303057
[INFO] running `Command { std: "docker" "start" "-a" "d46e6479c0f53189c573e16abe422e21c2e7d1ba247723db0caa32b08c303057", kill_on_drop: false }`
[INFO] [stderr]     Checking bitvector v0.1.5
[INFO] [stderr]     Checking bit-vec v0.8.0
[INFO] [stderr]     Checking compress v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `huffman::Tree`
[INFO] [stdout]  --> src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use huffman::Tree;
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `BinaryHeap`, `HashMap`, and `cmp::Reverse`
[INFO] [stdout]  --> src/huffman.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 |     cmp::Reverse,
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 3 |     collections::{BinaryHeap, HashMap},
[INFO] [stdout]   |                   ^^^^^^^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `huffman::Tree`
[INFO] [stdout]  --> src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use huffman::Tree;
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `BinaryHeap`, `HashMap`, and `cmp::Reverse`
[INFO] [stdout]  --> src/huffman.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 |     cmp::Reverse,
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 3 |     collections::{BinaryHeap, HashMap},
[INFO] [stdout]   |                   ^^^^^^^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `decoding_table`
[INFO] [stdout]   --> src/main.rs:89:9
[INFO] [stdout]    |
[INFO] [stdout] 89 |     let decoding_table = create_decoding_table(&tokens);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_decoding_table`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `decoding_table`
[INFO] [stdout]   --> src/main.rs:89:9
[INFO] [stdout]    |
[INFO] [stdout] 89 |     let decoding_table = create_decoding_table(&tokens);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_decoding_table`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Node` and `Leaf` are never constructed
[INFO] [stdout]   --> src/huffman.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout]  9 | pub enum Tree<T> {
[INFO] [stdout]    |          ---- variants in this enum
[INFO] [stdout] 10 |     Node {
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 15 |     Leaf {
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Tree` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Node` and `Leaf` are never constructed
[INFO] [stdout]   --> src/huffman.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout]  9 | pub enum Tree<T> {
[INFO] [stdout]    |          ---- variants in this enum
[INFO] [stdout] 10 |     Node {
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 15 |     Leaf {
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Tree` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.17s
[INFO] running `Command { std: "docker" "inspect" "d46e6479c0f53189c573e16abe422e21c2e7d1ba247723db0caa32b08c303057", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d46e6479c0f53189c573e16abe422e21c2e7d1ba247723db0caa32b08c303057", kill_on_drop: false }`
[INFO] [stdout] d46e6479c0f53189c573e16abe422e21c2e7d1ba247723db0caa32b08c303057