[INFO] cloning repository https://github.com/trickypr/huffman-coding
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/trickypr/huffman-coding" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftrickypr%2Fhuffman-coding", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftrickypr%2Fhuffman-coding'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 34414e9ee0e6569b390e3457071e6fb905494d75
[INFO] checking trickypr/huffman-coding against master#9fa580b1175018b0a276b0bc68f9827a106f7260 for pr-82565
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftrickypr%2Fhuffman-coding" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/trickypr/huffman-coding on toolchain 9fa580b1175018b0a276b0bc68f9827a106f7260
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9fa580b1175018b0a276b0bc68f9827a106f7260" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/trickypr/huffman-coding
[INFO] finished tweaking git repo https://github.com/trickypr/huffman-coding
[INFO] tweaked toml for git repo https://github.com/trickypr/huffman-coding written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/trickypr/huffman-coding already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9fa580b1175018b0a276b0bc68f9827a106f7260" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+9fa580b1175018b0a276b0bc68f9827a106f7260" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] c97c1efc077dcf547a9e139b4ec48eda259ece60f29a3475c7d46508cca3130d
[INFO] running `Command { std: "docker" "start" "-a" "c97c1efc077dcf547a9e139b4ec48eda259ece60f29a3475c7d46508cca3130d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c97c1efc077dcf547a9e139b4ec48eda259ece60f29a3475c7d46508cca3130d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c97c1efc077dcf547a9e139b4ec48eda259ece60f29a3475c7d46508cca3130d", kill_on_drop: false }`
[INFO] [stdout] c97c1efc077dcf547a9e139b4ec48eda259ece60f29a3475c7d46508cca3130d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+9fa580b1175018b0a276b0bc68f9827a106f7260" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b6a89b1f634ae69bc2ee3ea3d2e13e654fabadc6ecb414346fa3a6d71dfbf30f
[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" "b6a89b1f634ae69bc2ee3ea3d2e13e654fabadc6ecb414346fa3a6d71dfbf30f", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.21
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling syn v1.0.40
[INFO] [stderr]    Compiling serde_derive v1.0.115
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]     Checking itoa v0.4.6
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]     Checking huffman-coding v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `iter::FromIterator`
[INFO] [stdout]  --> src/main.rs:1:52
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{fs, fs::File, io::prelude::*, io::Error, iter::FromIterator, path::Path};
[INFO] [stdout]   |                                                    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `generate_tree`, `utils::bits_to_bytes`
[INFO] [stdout]  --> src/main.rs:6:29
[INFO] [stdout]   |
[INFO] [stdout] 6 |     compression::{compress, generate_tree},
[INFO] [stdout]   |                             ^^^^^^^^^^^^^
[INFO] [stdout] 7 |     decompression::decompress,
[INFO] [stdout] 8 |     utils::bits_to_bytes,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `iter::FromIterator`
[INFO] [stdout]  --> src/main.rs:1:52
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{fs, fs::File, io::prelude::*, io::Error, iter::FromIterator, path::Path};
[INFO] [stdout]   |                                                    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `generate_tree`, `utils::bits_to_bytes`
[INFO] [stdout]  --> src/main.rs:6:29
[INFO] [stdout]   |
[INFO] [stdout] 6 |     compression::{compress, generate_tree},
[INFO] [stdout]   |                             ^^^^^^^^^^^^^
[INFO] [stdout] 7 |     decompression::decompress,
[INFO] [stdout] 8 |     utils::bits_to_bytes,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/lib/compression/compression_pair.rs:96:28
[INFO] [stdout]    |
[INFO] [stdout] 96 |                     panic!(format!("The character '{}' is not in the huffman tree", c));
[INFO] [stdout]    |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_fmt_panic)]` on by default
[INFO] [stdout]    = note: this is no longer accepted in Rust 2021
[INFO] [stdout]    = note: the panic!() macro supports formatting, so there's no need for the format!() macro here
[INFO] [stdout] help: remove the `format!(..)` macro call
[INFO] [stdout]    |
[INFO] [stdout] 96 |                     panic!("The character '{}' is not in the huffman tree", c);
[INFO] [stdout]    |                           --                                                --
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/lib/compression/compression_pair.rs:96:28
[INFO] [stdout]    |
[INFO] [stdout] 96 |                     panic!(format!("The character '{}' is not in the huffman tree", c));
[INFO] [stdout]    |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_fmt_panic)]` on by default
[INFO] [stdout]    = note: this is no longer accepted in Rust 2021
[INFO] [stdout]    = note: the panic!() macro supports formatting, so there's no need for the format!() macro here
[INFO] [stdout] help: remove the `format!(..)` macro call
[INFO] [stdout]    |
[INFO] [stdout] 96 |                     panic!("The character '{}' is not in the huffman tree", c);
[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 31.85s
[INFO] running `Command { std: "docker" "inspect" "b6a89b1f634ae69bc2ee3ea3d2e13e654fabadc6ecb414346fa3a6d71dfbf30f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b6a89b1f634ae69bc2ee3ea3d2e13e654fabadc6ecb414346fa3a6d71dfbf30f", kill_on_drop: false }`
[INFO] [stdout] b6a89b1f634ae69bc2ee3ea3d2e13e654fabadc6ecb414346fa3a6d71dfbf30f