[INFO] fetching crate pyrus-nn 0.2.1...
[INFO] testing pyrus-nn-0.2.1 against 1.55.0 for beta-1.56-1
[INFO] extracting crate pyrus-nn 0.2.1 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate pyrus-nn 0.2.1 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate pyrus-nn 0.2.1
[INFO] finished tweaking crates.io crate pyrus-nn 0.2.1
[INFO] tweaked toml for crates.io crate pyrus-nn 0.2.1 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9a93ca646d3084219cb6b0c0cbb4152568430f8c5e4b390c390beaa9a66a9966
[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" "9a93ca646d3084219cb6b0c0cbb4152568430f8c5e4b390c390beaa9a66a9966", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9a93ca646d3084219cb6b0c0cbb4152568430f8c5e4b390c390beaa9a66a9966", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9a93ca646d3084219cb6b0c0cbb4152568430f8c5e4b390c390beaa9a66a9966", kill_on_drop: false }`
[INFO] [stdout] 9a93ca646d3084219cb6b0c0cbb4152568430f8c5e4b390c390beaa9a66a9966
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 256d36e8ce59a21f8cdcf353a518956939d78f67b4b4d3af6ae17015846ff0e5
[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" "256d36e8ce59a21f8cdcf353a518956939d78f67b4b4d3af6ae17015846ff0e5", kill_on_drop: false }`
[INFO] [stderr]    Compiling spin v0.4.10
[INFO] [stderr]    Compiling mashup-impl v0.1.13+deprecated
[INFO] [stderr]    Compiling float-cmp v0.4.0
[INFO] [stderr]    Compiling ctor v0.1.21
[INFO] [stderr]    Compiling pyo3-derive-backend v0.5.4
[INFO] [stderr]    Compiling ghost v0.1.2
[INFO] [stderr]    Compiling pyo3 v0.5.4
[INFO] [stderr]    Compiling inventory-impl v0.1.10
[INFO] [stderr]    Compiling typetag-impl v0.1.7
[INFO] [stderr]    Compiling ndarray v0.12.1
[INFO] [stderr]    Compiling erased-serde v0.3.16
[INFO] [stderr]    Compiling serde_json v1.0.67
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/spin-0.4.10/src/lib.rs:6:43
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![cfg_attr(feature = "const_fn", feature(const_fn))]
[INFO] [stdout]   |                                           ^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: split into finer-grained feature gates
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/spin-0.4.10/src/lib.rs:6:35
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![cfg_attr(feature = "const_fn", feature(const_fn))]
[INFO] [stdout]   |                                   ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `spin` due to 3 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "256d36e8ce59a21f8cdcf353a518956939d78f67b4b4d3af6ae17015846ff0e5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "256d36e8ce59a21f8cdcf353a518956939d78f67b4b4d3af6ae17015846ff0e5", kill_on_drop: false }`
[INFO] [stdout] 256d36e8ce59a21f8cdcf353a518956939d78f67b4b4d3af6ae17015846ff0e5