[INFO] fetching crate iref-enum 1.2.0...
[INFO] checking iref-enum-1.2.0 against beta for pr-78714
[INFO] extracting crate iref-enum 1.2.0 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate iref-enum 1.2.0 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 iref-enum 1.2.0
[INFO] finished tweaking crates.io crate iref-enum 1.2.0
[INFO] tweaked toml for crates.io crate iref-enum 1.2.0 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate crates.io crate iref-enum 1.2.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 592594a76538d95d07cda2666a431872b3712c3391ba1975d4a6e8b4cfed0426
[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" "592594a76538d95d07cda2666a431872b3712c3391ba1975d4a6e8b4cfed0426", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "592594a76538d95d07cda2666a431872b3712c3391ba1975d4a6e8b4cfed0426", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "592594a76538d95d07cda2666a431872b3712c3391ba1975d4a6e8b4cfed0426", kill_on_drop: false }`
[INFO] [stdout] 592594a76538d95d07cda2666a431872b3712c3391ba1975d4a6e8b4cfed0426
[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=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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0d3229c152b354f3ff8ca4a714c738b1f3dbd2b5503e7fd3bfee89411d1ae4a5
[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" "0d3229c152b354f3ff8ca4a714c738b1f3dbd2b5503e7fd3bfee89411d1ae4a5", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.44
[INFO] [stderr]    Compiling pct-str v1.1.0
[INFO] [stderr]     Checking iref v1.4.0
[INFO] [stderr]    Compiling static-iref v1.0.0
[INFO] [stderr]     Checking iref-enum v1.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> examples/simple.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(proc_macro_hygiene)]
[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 `iref-enum`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "0d3229c152b354f3ff8ca4a714c738b1f3dbd2b5503e7fd3bfee89411d1ae4a5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0d3229c152b354f3ff8ca4a714c738b1f3dbd2b5503e7fd3bfee89411d1ae4a5", kill_on_drop: false }`
[INFO] [stdout] 0d3229c152b354f3ff8ca4a714c738b1f3dbd2b5503e7fd3bfee89411d1ae4a5