[INFO] cloning repository https://github.com/MSleepyPanda/explain-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/MSleepyPanda/explain-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMSleepyPanda%2Fexplain-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMSleepyPanda%2Fexplain-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 10522cf5c80910dfa6a0c1db49360ecef247cf89
[INFO] testing MSleepyPanda/explain-rs 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%2FMSleepyPanda%2Fexplain-rs" "/workspace/builds/worker-14/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-14/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/MSleepyPanda/explain-rs 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/MSleepyPanda/explain-rs
[INFO] finished tweaking git repo https://github.com/MSleepyPanda/explain-rs
[INFO] tweaked toml for git repo https://github.com/MSleepyPanda/explain-rs written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate git repo https://github.com/MSleepyPanda/explain-rs 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]     Updating git repository `https://github.com/shepmaster/fuzzy-pickles`
[INFO] [stderr]     Updating git repository `https://github.com/servo/rust-url`
[INFO] [stderr]     Updating git repository `https://github.com/shepmaster/peresil`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded sha1 v0.3.0
[INFO] [stderr]   Downloaded stdweb v0.2.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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] 0a29c089b1a0401030425029c4917ed55a1bb31b25dc2fcd954b1f6905a929b3
[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" "0a29c089b1a0401030425029c4917ed55a1bb31b25dc2fcd954b1f6905a929b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0a29c089b1a0401030425029c4917ed55a1bb31b25dc2fcd954b1f6905a929b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0a29c089b1a0401030425029c4917ed55a1bb31b25dc2fcd954b1f6905a929b3", kill_on_drop: false }`
[INFO] [stdout] 0a29c089b1a0401030425029c4917ed55a1bb31b25dc2fcd954b1f6905a929b3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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] 9f0a4ee70603c0394804228d097f0becf8da5bd265891c6a6f898c58a47c373d
[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" "9f0a4ee70603c0394804228d097f0becf8da5bd265891c6a6f898c58a47c373d", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.1.41
[INFO] [stderr]    Compiling serde v1.0.24
[INFO] [stderr]    Compiling either v1.4.0
[INFO] [stderr]    Compiling percent-encoding v1.0.1 (https://github.com/servo/rust-url#027450de)
[INFO] [stderr]    Compiling peresil v0.3.0 (https://github.com/shepmaster/peresil#6e4f794b)
[INFO] [stderr]    Compiling sha1 v0.3.0
[INFO] [stderr]    Compiling idna v0.1.4 (https://github.com/servo/rust-url#027450de)
[INFO] [stderr]    Compiling serde_derive_internals v0.18.0
[INFO] [stderr]    Compiling fuzzy-pickles-derive v0.1.0 (https://github.com/shepmaster/fuzzy-pickles#abf5ae5b)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/git/checkouts/peresil-7403d1c1394b7448/6e4f794/src/lib.rs:1:38
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(feature = "combinators", feature(conservative_impl_trait))]
[INFO] [stdout]   |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr]    Compiling itertools v0.7.5
[INFO] [stderr] error: could not compile `peresil`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "9f0a4ee70603c0394804228d097f0becf8da5bd265891c6a6f898c58a47c373d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f0a4ee70603c0394804228d097f0becf8da5bd265891c6a6f898c58a47c373d", kill_on_drop: false }`
[INFO] [stdout] 9f0a4ee70603c0394804228d097f0becf8da5bd265891c6a6f898c58a47c373d