[INFO] fetching crate pyrus-nn 0.2.1...
[INFO] testing pyrus-nn-0.2.1 against 1.44.0 for beta-1.45-1
[INFO] extracting crate pyrus-nn 0.2.1 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate pyrus-nn 0.2.1 on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[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-3/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.44.0" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] a2e3cae3ed2d32bad279604262587d0accde7afb0d3817ac1d6f0f292d3e071b
[INFO] running `"docker" "start" "-a" "a2e3cae3ed2d32bad279604262587d0accde7afb0d3817ac1d6f0f292d3e071b"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling matrixmultiply v0.1.15
[INFO] [stderr]    Compiling proc-macro-hack-impl v0.4.2
[INFO] [stderr]    Compiling rawpointer v0.1.0
[INFO] [stderr]    Compiling ndarray v0.12.1
[INFO] [stderr]    Compiling spin v0.4.10
[INFO] [stderr]    Compiling dtoa v0.4.5
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]    Compiling itertools v0.7.11
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling pyo3-derive-backend v0.5.4
[INFO] [stderr]    Compiling float-cmp v0.4.0
[INFO] [stderr]    Compiling pyo3 v0.5.4
[INFO] [stderr]    Compiling ghost v0.1.1
[INFO] [stderr]    Compiling ctor v0.1.14
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/spin-0.4.10/src/lib.rs:6:35
[INFO] [stderr]   |
[INFO] [stderr] 6 | #![cfg_attr(feature = "const_fn", feature(const_fn))]
[INFO] [stderr]   |                                   ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]    Compiling inventory-impl v0.1.6
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `spin`.
[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 `"docker" "inspect" "a2e3cae3ed2d32bad279604262587d0accde7afb0d3817ac1d6f0f292d3e071b"`
[INFO] running `"docker" "rm" "-f" "a2e3cae3ed2d32bad279604262587d0accde7afb0d3817ac1d6f0f292d3e071b"`
[INFO] [stdout] a2e3cae3ed2d32bad279604262587d0accde7afb0d3817ac1d6f0f292d3e071b