[INFO] cloning repository https://github.com/pandawithcat/cs290_hw1
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/pandawithcat/cs290_hw1" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpandawithcat%2Fcs290_hw1", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpandawithcat%2Fcs290_hw1'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e653024ba2d05552ab38fcfab26f7ebe1b5913c3
[INFO] checking pandawithcat/cs290_hw1 against master#af4a5a13a15fa0c60e06321077ef452f769b42fd for pr-122960-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpandawithcat%2Fcs290_hw1" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/pandawithcat/cs290_hw1 on toolchain af4a5a13a15fa0c60e06321077ef452f769b42fd
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/pandawithcat/cs290_hw1
[INFO] finished tweaking git repo https://github.com/pandawithcat/cs290_hw1
[INFO] tweaked toml for git repo https://github.com/pandawithcat/cs290_hw1 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/pandawithcat/cs290_hw1 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" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded bit-vec v0.6.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a08f3226cf13748e545540401a2f2f50074a07d6b41e2518c5d7662a2e29c277
[INFO] running `Command { std: "docker" "start" "-a" "a08f3226cf13748e545540401a2f2f50074a07d6b41e2518c5d7662a2e29c277", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a08f3226cf13748e545540401a2f2f50074a07d6b41e2518c5d7662a2e29c277", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a08f3226cf13748e545540401a2f2f50074a07d6b41e2518c5d7662a2e29c277", kill_on_drop: false }`
[INFO] [stdout] a08f3226cf13748e545540401a2f2f50074a07d6b41e2518c5d7662a2e29c277
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 77c0658b7d35e1d1264b2b69e045e52a7d4808fd8e1086e603eb90f32363886e
[INFO] running `Command { std: "docker" "start" "-a" "77c0658b7d35e1d1264b2b69e045e52a7d4808fd8e1086e603eb90f32363886e", kill_on_drop: false }`
[INFO] [stderr]     Checking bit-vec v0.6.2
[INFO] [stderr]     Checking hw1 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Vec` is imported redundantly
[INFO] [stdout]  --> src/huffman.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::vec::Vec;
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/af4a5a13a15fa0c60e06321077ef452f769b42fd/library/std/src/prelude/mod.rs:134:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Vec` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Vec` is imported redundantly
[INFO] [stdout]  --> src/huffman.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::vec::Vec;
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]  --> /rustc/af4a5a13a15fa0c60e06321077ef452f769b42fd/library/std/src/prelude/mod.rs:134:13
[INFO] [stdout]   |
[INFO] [stdout]   = note: the item `Vec` is already defined here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `Tree` doesn't implement `Debug`
[INFO] [stdout]   --> src/huffman.rs:22:47
[INFO] [stdout]    |
[INFO] [stdout] 22 |     println!("This is the huffman tree {:?}", tree);
[INFO] [stdout]    |                                               ^^^^ `Tree` cannot be formatted using `{:?}`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Debug` is not implemented for `Tree`
[INFO] [stdout]    = note: add `#[derive(Debug)]` to `Tree` or manually `impl Debug for Tree`
[INFO] [stdout]    = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: `Tree` doesn't implement `Debug`
[INFO] [stdout]   --> src/huffman.rs:22:47
[INFO] [stdout]    |
[INFO] [stdout] 22 |     println!("This is the huffman tree {:?}", tree);
[INFO] [stdout]    |                                               ^^^^ `Tree` cannot be formatted using `{:?}`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Debug` is not implemented for `Tree`
[INFO] [stdout]    = note: add `#[derive(Debug)]` to `Tree` or manually `impl Debug for Tree`
[INFO] [stdout]    = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `hw1` (bin "hw1" test) due to 2 previous errors; 1 warning emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `hw1` (bin "hw1") due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "77c0658b7d35e1d1264b2b69e045e52a7d4808fd8e1086e603eb90f32363886e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "77c0658b7d35e1d1264b2b69e045e52a7d4808fd8e1086e603eb90f32363886e", kill_on_drop: false }`
[INFO] [stdout] 77c0658b7d35e1d1264b2b69e045e52a7d4808fd8e1086e603eb90f32363886e