[INFO] fetching crate spartan 0.2.1...
[INFO] testing spartan-0.2.1 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate spartan 0.2.1 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate spartan 0.2.1 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 crates.io crate spartan 0.2.1
[INFO] finished tweaking crates.io crate spartan 0.2.1
[INFO] tweaked toml for crates.io crate spartan 0.2.1 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate spartan 0.2.1 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 criterion v0.3.2
[INFO] [stderr]   Downloaded oorandom v11.1.1
[INFO] [stderr]   Downloaded wasm-bindgen-backend v0.2.62
[INFO] [stderr]   Downloaded js-sys v0.3.39
[INFO] [stderr]   Downloaded packed_simd v0.3.3
[INFO] [stderr]   Downloaded wasm-bindgen-macro v0.2.62
[INFO] [stderr]   Downloaded wasm-bindgen-shared v0.2.62
[INFO] [stderr]   Downloaded serde_json v1.0.52
[INFO] [stderr]   Downloaded tinytemplate v1.0.4
[INFO] [stderr]   Downloaded criterion-plot v0.4.2
[INFO] [stderr]   Downloaded wasm-bindgen-macro-support v0.2.62
[INFO] [stderr]   Downloaded web-sys v0.3.39
[INFO] [stderr]   Downloaded merlin v2.0.0
[INFO] [stderr]   Downloaded curve25519-dalek v2.0.0
[INFO] [stderr]   Downloaded bumpalo v3.2.1
[INFO] [stderr]   Downloaded wasm-bindgen v0.2.62
[INFO] [stderr]   Downloaded hermit-abi v0.1.12
[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" "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] 72a81dd79c18ea87d11a7498c7c4cdb1d1b7143c26473e4efa019fe785bba0b3
[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" "72a81dd79c18ea87d11a7498c7c4cdb1d1b7143c26473e4efa019fe785bba0b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "72a81dd79c18ea87d11a7498c7c4cdb1d1b7143c26473e4efa019fe785bba0b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "72a81dd79c18ea87d11a7498c7c4cdb1d1b7143c26473e4efa019fe785bba0b3", kill_on_drop: false }`
[INFO] [stdout] 72a81dd79c18ea87d11a7498c7c4cdb1d1b7143c26473e4efa019fe785bba0b3
[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" "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] 82bfb51fd65c07dc437799d1bdac7453a01aff2c99ae4c881c72a474397ccd0a
[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" "82bfb51fd65c07dc437799d1bdac7453a01aff2c99ae4c881c72a474397ccd0a", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.69
[INFO] [stderr]    Compiling proc-macro2 v1.0.12
[INFO] [stderr]    Compiling syn v1.0.18
[INFO] [stderr]    Compiling serde v1.0.106
[INFO] [stderr]    Compiling packed_simd v0.3.3
[INFO] [stderr]    Compiling crc32fast v1.2.0
[INFO] [stderr]    Compiling rayon-core v1.7.0
[INFO] [stderr]    Compiling subtle v2.2.3
[INFO] [stderr]    Compiling memoffset v0.5.4
[INFO] [stderr]    Compiling miniz_oxide v0.4.0
[INFO] [stderr]    Compiling itertools v0.9.0
[INFO] [stderr]    Compiling crossbeam-queue v0.2.1
[INFO] [stderr]    Compiling sha3 v0.8.2
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/subtle-2.2.3/src/lib.rs:12:34
[INFO] [stdout]    |
[INFO] [stdout] 12 | #![cfg_attr(feature = "nightly", feature(external_doc))]
[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] error: could not compile `subtle`
[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" "82bfb51fd65c07dc437799d1bdac7453a01aff2c99ae4c881c72a474397ccd0a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "82bfb51fd65c07dc437799d1bdac7453a01aff2c99ae4c881c72a474397ccd0a", kill_on_drop: false }`
[INFO] [stdout] 82bfb51fd65c07dc437799d1bdac7453a01aff2c99ae4c881c72a474397ccd0a