[INFO] fetching crate cpclib-tokens 0.4.2-alpha...
[INFO] testing cpclib-tokens-0.4.2-alpha against 1.47.0 for beta-1.48-1
[INFO] extracting crate cpclib-tokens 0.4.2-alpha into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate cpclib-tokens 0.4.2-alpha on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate cpclib-tokens 0.4.2-alpha
[INFO] finished tweaking crates.io crate cpclib-tokens 0.4.2-alpha
[INFO] tweaked toml for crates.io crate cpclib-tokens 0.4.2-alpha written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2612139b6d2a752d926c0d1fb246dea4b5aec6b4f254eca67fcbcbf5121eec64
[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" "2612139b6d2a752d926c0d1fb246dea4b5aec6b4f254eca67fcbcbf5121eec64", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2612139b6d2a752d926c0d1fb246dea4b5aec6b4f254eca67fcbcbf5121eec64", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2612139b6d2a752d926c0d1fb246dea4b5aec6b4f254eca67fcbcbf5121eec64", kill_on_drop: false }`
[INFO] [stdout] 2612139b6d2a752d926c0d1fb246dea4b5aec6b4f254eca67fcbcbf5121eec64
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "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] d0b88a87df5fd8f50bac6171586599c95d030e55782aecc53dd1f170827e7369
[INFO] running `Command { std: "docker" "start" "-a" "d0b88a87df5fd8f50bac6171586599c95d030e55782aecc53dd1f170827e7369", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling bitsets v0.1.1
[INFO] [stderr]    Compiling paste-impl v0.1.18
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling nom v5.1.2
[INFO] [stderr]    Compiling derivative v2.1.1
[INFO] [stderr]    Compiling remain v0.2.2
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling num_enum_derive v0.4.3
[INFO] [stderr]    Compiling cargo-lock v4.0.1
[INFO] [stderr]    Compiling paste v0.1.18
[INFO] [stderr]    Compiling built v0.4.3
[INFO] [stderr]    Compiling cpclib-sna v0.4.2-alpha
[INFO] [stderr]    Compiling cpclib-tokens v0.4.2-alpha (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling num_enum v0.4.3
[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/cpclib-sna-0.4.2-alpha/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(vec_drain_as_slice)]
[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 `cpclib-sna`.
[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" "d0b88a87df5fd8f50bac6171586599c95d030e55782aecc53dd1f170827e7369", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d0b88a87df5fd8f50bac6171586599c95d030e55782aecc53dd1f170827e7369", kill_on_drop: false }`
[INFO] [stdout] d0b88a87df5fd8f50bac6171586599c95d030e55782aecc53dd1f170827e7369
