[INFO] fetching crate muta-keypair 0.1.0-alpha.1...
[INFO] testing muta-keypair-0.1.0-alpha.1 against 1.49.0 for beta-1.50-1
[INFO] extracting crate muta-keypair 0.1.0-alpha.1 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate muta-keypair 0.1.0-alpha.1 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate muta-keypair 0.1.0-alpha.1
[INFO] finished tweaking crates.io crate muta-keypair 0.1.0-alpha.1
[INFO] tweaked toml for crates.io crate muta-keypair 0.1.0-alpha.1 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate crates.io crate muta-keypair 0.1.0-alpha.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9c9d00d8e1148d1b58dca1047891c91f4d8db8e915c2b51011ac72458ad65f52
[INFO] running `Command { std: "docker" "start" "-a" "9c9d00d8e1148d1b58dca1047891c91f4d8db8e915c2b51011ac72458ad65f52", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9c9d00d8e1148d1b58dca1047891c91f4d8db8e915c2b51011ac72458ad65f52", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9c9d00d8e1148d1b58dca1047891c91f4d8db8e915c2b51011ac72458ad65f52", kill_on_drop: false }`
[INFO] [stdout] 9c9d00d8e1148d1b58dca1047891c91f4d8db8e915c2b51011ac72458ad65f52
[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" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 49e429362b1a70ae766eb6e7861c04f05f43270e8b9649384675dec7538db228
[INFO] running `Command { std: "docker" "start" "-a" "49e429362b1a70ae766eb6e7861c04f05f43270e8b9649384675dec7538db228", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.7
[INFO] [stderr]    Compiling syn v1.0.13
[INFO] [stderr]    Compiling rustc-hex v2.0.1
[INFO] [stderr]    Compiling crunchy v0.2.2
[INFO] [stderr]    Compiling heapsize v0.4.2
[INFO] [stderr]    Compiling crunchy v0.1.6
[INFO] [stderr]    Compiling bytes v0.5.3
[INFO] [stderr]    Compiling futures-core v0.3.1
[INFO] [stderr]    Compiling keccak v0.1.0
[INFO] [stderr]    Compiling futures-sink v0.3.1
[INFO] [stderr]    Compiling miracl_amcl v3.2.5
[INFO] [stderr]    Compiling futures-task v0.3.1
[INFO] [stderr]    Compiling futures-io v0.3.1
[INFO] [stderr]    Compiling hashbrown v0.3.1
[INFO] [stderr]    Compiling creep v0.1.1
[INFO] [stderr]    Compiling unsigned-varint v0.2.3
[INFO] [stderr]    Compiling bs58 v0.2.5
[INFO] [stderr]    Compiling json v0.12.0
[INFO] [stderr]    Compiling hex v0.4.0
[INFO] [stderr]    Compiling backtrace-sys v0.1.32
[INFO] [stderr]    Compiling num-traits v0.2.10
[INFO] [stderr]    Compiling secp256k1-sys v0.1.1
[INFO] [stderr]    Compiling num-integer v0.1.41
[INFO] [stderr]    Compiling lock_api v0.2.0
[INFO] [stderr]    Compiling secp256k1 v0.15.5
[INFO] [stderr]    Compiling num-bigint v0.2.4
[INFO] [stderr]    Compiling ring v0.16.9
[INFO] [stderr]    Compiling futures-channel v0.3.1
[INFO] [stderr]    Compiling rlp v0.4.4
[INFO] [stderr]    Compiling parking_lot_core v0.5.0
[INFO] [stderr]    Compiling parking_lot v0.8.0
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling clap v2.33.0
[INFO] [stderr]    Compiling stream-cipher v0.3.2
[INFO] [stderr]    Compiling flatbuffers v0.6.0
[INFO] [stderr]    Compiling mio-uds v0.6.7
[INFO] [stderr]    Compiling sha3 v0.8.2
[INFO] [stderr]    Compiling sha2 v0.8.1
[INFO] [stderr]    Compiling aes-soft v0.3.3
[INFO] [stderr]    Compiling twofish v0.2.0
[INFO] [stderr]    Compiling tiny-keccak v1.5.0
[INFO] [stderr]    Compiling derive_more v0.15.0
[INFO] [stderr]    Compiling rand v0.7.2
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling impl-rlp v0.2.1
[INFO] [stderr]    Compiling ctr v0.3.2
[INFO] [stderr]    Compiling fixed-hash v0.2.5
[INFO] [stderr]    Compiling uint v0.4.1
[INFO] [stderr]    Compiling zeroize_derive v0.9.3
[INFO] [stderr]    Compiling tokio-io v0.1.12
[INFO] [stderr]    Compiling flatbuffers-verifier v0.2.1
[INFO] [stderr]    Compiling hasher v0.1.3
[INFO] [stderr]    Compiling aes-ctr v0.3.0
[INFO] [stderr]    Compiling backtrace v0.3.40
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling secp256k1 v0.17.1
[INFO] [stderr]    Compiling fixed-hash v0.5.2
[INFO] [stderr]    Compiling tokio-reactor v0.1.11
[INFO] [stderr]    Compiling tokio-codec v0.1.1
[INFO] [stderr]    Compiling tokio-fs v0.1.6
[INFO] [stderr]    Compiling zeroize v0.9.3
[INFO] [stderr]    Compiling tokio-udp v0.1.5
[INFO] [stderr]    Compiling tokio-uds v0.2.5
[INFO] [stderr]    Compiling tokio-tcp v0.1.3
[INFO] [stderr]    Compiling tokio v0.1.22
[INFO] [stderr]    Compiling tentacle-secio v0.1.11
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling proc-macro-hack v0.5.11
[INFO] [stderr]    Compiling thiserror-impl v1.0.9
[INFO] [stderr]    Compiling ophelia-derive v0.2.0
[INFO] [stderr]    Compiling async-trait v0.1.22
[INFO] [stderr]    Compiling failure v0.1.6
[INFO] [stderr]    Compiling futures-macro v0.3.1
[INFO] [stderr]    Compiling thiserror v1.0.9
[INFO] [stderr]    Compiling muta-vendor-prost-derive v0.5.1
[INFO] [stderr]    Compiling ophelia-hasher v0.2.0
[INFO] [stderr]    Compiling ophelia v0.2.0
[INFO] [stderr]    Compiling ophelia-secp256k1 v0.2.0
[INFO] [stderr]    Compiling futures-util v0.3.1
[INFO] [stderr]    Compiling muta-vendor-prost v0.5.1
[INFO] [stderr]    Compiling futures-executor v0.3.1
[INFO] [stderr]    Compiling futures v0.3.1
[INFO] [stderr]    Compiling serde v1.0.104
[INFO] [stderr]    Compiling serde_json v1.0.44
[INFO] [stderr]    Compiling ethereum-types-serialize v0.2.2
[INFO] [stderr]    Compiling impl-serde v0.2.3
[INFO] [stderr]    Compiling bincode v1.2.1
[INFO] [stderr]    Compiling ethbloom v0.5.3
[INFO] [stderr]    Compiling ethbloom v0.8.1
[INFO] [stderr]    Compiling ethereum-types v0.4.2
[INFO] [stderr]    Compiling amcl_wrapper v0.2.3
[INFO] [stderr]    Compiling rlp v0.3.0
[INFO] [stderr]    Compiling secret_sharing v0.1.1
[INFO] [stderr]    Compiling cita_trie v2.0.0
[INFO] [stderr]    Compiling bls_amcl v0.7.0
[INFO] [stderr]    Compiling muta-protocol v0.1.0-alpha.0
[INFO] [stderr]    Compiling ophelia-bls-amcl v0.1.0
[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/muta-protocol-0.1.0-alpha.0/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[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 `muta-protocol`
[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" "49e429362b1a70ae766eb6e7861c04f05f43270e8b9649384675dec7538db228", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "49e429362b1a70ae766eb6e7861c04f05f43270e8b9649384675dec7538db228", kill_on_drop: false }`
[INFO] [stdout] 49e429362b1a70ae766eb6e7861c04f05f43270e8b9649384675dec7538db228