[INFO] fetching crate sarek 0.1.0...
[INFO] checking sarek-0.1.0 against beta for pr-78714
[INFO] extracting crate sarek 0.1.0 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate sarek 0.1.0 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate sarek 0.1.0
[INFO] finished tweaking crates.io crate sarek 0.1.0
[INFO] tweaked toml for crates.io crate sarek 0.1.0 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "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-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 132d0a8371eeac89601c9dd723701cabd554072038dcad399b311da1891422d1
[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" "132d0a8371eeac89601c9dd723701cabd554072038dcad399b311da1891422d1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "132d0a8371eeac89601c9dd723701cabd554072038dcad399b311da1891422d1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "132d0a8371eeac89601c9dd723701cabd554072038dcad399b311da1891422d1", kill_on_drop: false }`
[INFO] [stdout] 132d0a8371eeac89601c9dd723701cabd554072038dcad399b311da1891422d1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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=forbid" "-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" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3e56c1748d3a0add237ebc351971b7e5ee19cedb9238b870882f5880e9e8f905
[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" "3e56c1748d3a0add237ebc351971b7e5ee19cedb9238b870882f5880e9e8f905", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro-hack-impl v0.4.2
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking stable_deref_trait v1.2.0
[INFO] [stderr]     Checking spin v0.4.10
[INFO] [stderr]     Checking panic-control v0.1.4
[INFO] [stderr]     Checking flate2 v1.0.19
[INFO] [stderr]    Compiling pyo3 v0.5.4
[INFO] [stderr]     Checking decorum v0.1.3
[INFO] [stderr]     Checking uuid v0.7.4
[INFO] [stderr]     Checking parking_lot_core v0.4.0
[INFO] [stderr]     Checking env_logger v0.6.2
[INFO] [stderr]     Checking owning_ref v0.4.1
[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/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 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 `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 `Command { std: "docker" "inspect" "3e56c1748d3a0add237ebc351971b7e5ee19cedb9238b870882f5880e9e8f905", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3e56c1748d3a0add237ebc351971b7e5ee19cedb9238b870882f5880e9e8f905", kill_on_drop: false }`
[INFO] [stdout] 3e56c1748d3a0add237ebc351971b7e5ee19cedb9238b870882f5880e9e8f905