[INFO] cloning repository https://github.com/comp500/miniworld
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/comp500/miniworld" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcomp500%2Fminiworld", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcomp500%2Fminiworld'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5b1f8da5661d17ae0d23422f193f5750c58ce9b7
[INFO] testing comp500/miniworld against beta-2021-01-01 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcomp500%2Fminiworld" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/comp500/miniworld on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/comp500/miniworld
[INFO] finished tweaking git repo https://github.com/comp500/miniworld
[INFO] tweaked toml for git repo https://github.com/comp500/miniworld written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/comp500/miniworld already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded alloc-no-stdlib v2.0.1
[INFO] [stderr]   Downloaded num_enum v0.5.1
[INFO] [stderr]   Downloaded num_enum_derive v0.5.1
[INFO] [stderr]   Downloaded coercible_errors v0.1.4
[INFO] [stderr]   Downloaded arcode v0.1.2
[INFO] [stderr]   Downloaded hematite-nbt v0.5.0
[INFO] [stderr]   Downloaded defer v0.1.0
[INFO] [stderr]   Downloaded transmute v0.1.1
[INFO] [stderr]   Downloaded firestorm v0.3.0
[INFO] [stderr]   Downloaded brotli v3.3.0
[INFO] [stderr]   Downloaded gibbon v0.1.3
[INFO] [stderr]   Downloaded brotli-decompressor v2.3.1
[INFO] [stderr]   Downloaded simple-16 v0.2.0
[INFO] [stderr]   Downloaded fenwick v0.2.0
[INFO] [stderr]   Downloaded tree-buf v0.10.0
[INFO] [stderr]   Downloaded bitbit v0.2.0
[INFO] [stderr]   Downloaded alloc-stdlib v0.2.1
[INFO] [stderr]   Downloaded zigzag v0.1.0
[INFO] [stderr]   Downloaded tree-buf-macros v0.10.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 58d9add89d9bf253da2b53ceb10203c738444025f4fd8adaaff758f0252060d9
[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" "58d9add89d9bf253da2b53ceb10203c738444025f4fd8adaaff758f0252060d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "58d9add89d9bf253da2b53ceb10203c738444025f4fd8adaaff758f0252060d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "58d9add89d9bf253da2b53ceb10203c738444025f4fd8adaaff758f0252060d9", kill_on_drop: false }`
[INFO] [stdout] 58d9add89d9bf253da2b53ceb10203c738444025f4fd8adaaff758f0252060d9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] de1898c6fd77ca3b5f021a4800297b8561306b287945d62973a400802cd3c42c
[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" "de1898c6fd77ca3b5f021a4800297b8561306b287945d62973a400802cd3c42c", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.39
[INFO] [stderr]    Compiling alloc-no-stdlib v2.0.1
[INFO] [stderr]    Compiling firestorm v0.3.0
[INFO] [stderr]    Compiling transmute v0.1.1
[INFO] [stderr]    Compiling fenwick v0.2.0
[INFO] [stderr]    Compiling defer v0.1.0
[INFO] [stderr]    Compiling gibbon v0.1.3
[INFO] [stderr]    Compiling cesu8 v1.1.0
[INFO] [stderr]    Compiling bitbit v0.2.0
[INFO] [stderr]    Compiling error-chain v0.12.4
[INFO] [stderr]    Compiling miniz_oxide v0.3.7
[INFO] [stderr]    Compiling jobserver v0.1.21
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling deflate v0.8.6
[INFO] [stderr]    Compiling zigzag v0.1.0
[INFO] [stderr]    Compiling approx v0.3.2
[INFO] [stderr]    Compiling rand_pcg v0.2.1
[INFO] [stderr]    Compiling alloc-stdlib v0.2.1
[INFO] [stderr]    Compiling simple-16 v0.2.0
[INFO] [stderr]    Compiling arcode v0.1.2
[INFO] [stderr]    Compiling cc v1.0.59
[INFO] [stderr]    Compiling brotli-decompressor v2.3.1
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling png v0.16.7
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling random_color v0.4.4
[INFO] [stderr]    Compiling coercible_errors v0.1.4
[INFO] [stderr]    Compiling zstd-sys v1.4.17+zstd.1.4.5
[INFO] [stderr]    Compiling lzma-sys v0.1.16
[INFO] [stderr]    Compiling phf_generator v0.8.0
[INFO] [stderr]    Compiling phf_codegen v0.8.0
[INFO] [stderr]    Compiling palette v0.5.0
[INFO] [stderr]    Compiling brotli v3.3.0
[INFO] [stderr]    Compiling xz2 v0.1.6
[INFO] [stderr]    Compiling serde_derive v1.0.115
[INFO] [stderr]    Compiling palette_derive v0.5.0
[INFO] [stderr]    Compiling tree-buf-macros v0.10.0
[INFO] [stderr]    Compiling derivative v2.1.1
[INFO] [stderr]    Compiling tree-buf v0.10.0
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling toml v0.5.6
[INFO] [stderr]    Compiling hematite-nbt v0.5.0
[INFO] [stderr]    Compiling proc-macro-crate v0.1.5
[INFO] [stderr]    Compiling num_enum_derive v0.5.1
[INFO] [stderr]    Compiling num_enum v0.5.1
[INFO] [stderr]    Compiling zstd-safe v2.0.5+zstd.1.4.5
[INFO] [stderr]    Compiling zstd v0.5.3+zstd.1.4.5
[INFO] [stderr]    Compiling miniworld v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(drain_filter)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `BufWriter`, `Write`
[INFO] [stdout]  --> src/main.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 | use io::{BufWriter, Seek, SeekFrom, Read, Cursor, Write};
[INFO] [stdout]   |          ^^^^^^^^^                                ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `miniworld`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "de1898c6fd77ca3b5f021a4800297b8561306b287945d62973a400802cd3c42c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "de1898c6fd77ca3b5f021a4800297b8561306b287945d62973a400802cd3c42c", kill_on_drop: false }`
[INFO] [stdout] de1898c6fd77ca3b5f021a4800297b8561306b287945d62973a400802cd3c42c