[INFO] fetching crate revent 0.29.0...
[INFO] testing revent-0.29.0 against beta-2021-09-08 for beta-1.56-1
[INFO] extracting crate revent 0.29.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate revent 0.29.0 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate revent 0.29.0
[INFO] finished tweaking crates.io crate revent 0.29.0
[INFO] tweaked toml for crates.io crate revent 0.29.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate revent 0.29.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded criterion v0.3.2
[INFO] [stderr]   Downloaded criterion-plot v0.4.2
[INFO] [stderr]   Downloaded wasm-bindgen-backend v0.2.63
[INFO] [stderr]   Downloaded oorandom v11.1.1
[INFO] [stderr]   Downloaded serde_derive v1.0.111
[INFO] [stderr]   Downloaded serde v1.0.111
[INFO] [stderr]   Downloaded wasm-bindgen-shared v0.2.63
[INFO] [stderr]   Downloaded wasm-bindgen v0.2.63
[INFO] [stderr]   Downloaded wasm-bindgen-macro-support v0.2.63
[INFO] [stderr]   Downloaded wasm-bindgen-macro v0.2.63
[INFO] [stderr]   Downloaded crossbeam-queue v0.2.2
[INFO] [stderr]   Downloaded js-sys v0.3.40
[INFO] [stderr]   Downloaded web-sys v0.3.40
[INFO] [stderr]   Downloaded tinytemplate v1.1.0
[INFO] [stderr]   Downloaded isize-vec v0.1.1
[INFO] [stderr]   Downloaded plotters v0.2.15
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e9e4bb34a09c613fd7fd465181afae5f37fb54801eef667aee34a726c6b672e9
[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" "e9e4bb34a09c613fd7fd465181afae5f37fb54801eef667aee34a726c6b672e9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e9e4bb34a09c613fd7fd465181afae5f37fb54801eef667aee34a726c6b672e9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e9e4bb34a09c613fd7fd465181afae5f37fb54801eef667aee34a726c6b672e9", kill_on_drop: false }`
[INFO] [stdout] e9e4bb34a09c613fd7fd465181afae5f37fb54801eef667aee34a726c6b672e9
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "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] e7011b7eadde0b1d0732880c143cf41914b8324b5ad9422f059096139bb08d66
[INFO] running `Command { std: "docker" "start" "-a" "e7011b7eadde0b1d0732880c143cf41914b8324b5ad9422f059096139bb08d66", kill_on_drop: false }`
[INFO] [stderr]    Compiling isize-vec v0.1.1
[INFO] [stderr]    Compiling revent v0.29.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:63:1
[INFO] [stdout]    |
[INFO] [stdout] 63 | #![feature(coerce_unsized, drain_filter, unsize)]
[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 `revent` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "e7011b7eadde0b1d0732880c143cf41914b8324b5ad9422f059096139bb08d66", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e7011b7eadde0b1d0732880c143cf41914b8324b5ad9422f059096139bb08d66", kill_on_drop: false }`
[INFO] [stdout] e7011b7eadde0b1d0732880c143cf41914b8324b5ad9422f059096139bb08d66