[INFO] fetching crate revent 0.29.0...
[INFO] documenting revent-0.29.0 against 1.61.0 for beta-1.62-rustdoc-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 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "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" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tinytemplate v1.1.0
[INFO] [stderr]   Downloaded serde v1.0.111
[INFO] [stderr]   Downloaded crossbeam-queue v0.2.2
[INFO] [stderr]   Downloaded criterion v0.3.2
[INFO] [stderr]   Downloaded web-sys v0.3.40
[INFO] [stderr]   Downloaded js-sys v0.3.40
[INFO] [stderr]   Downloaded wasm-bindgen-macro v0.2.63
[INFO] [stderr]   Downloaded wasm-bindgen v0.2.63
[INFO] [stderr]   Downloaded criterion-plot v0.4.2
[INFO] [stderr]   Downloaded oorandom v11.1.1
[INFO] [stderr]   Downloaded wasm-bindgen-backend v0.2.63
[INFO] [stderr]   Downloaded wasm-bindgen-shared v0.2.63
[INFO] [stderr]   Downloaded wasm-bindgen-macro-support v0.2.63
[INFO] [stderr]   Downloaded serde_derive v1.0.111
[INFO] [stderr]   Downloaded plotters v0.2.15
[INFO] [stderr]   Downloaded isize-vec v0.1.1
[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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9ce28049ba1f9f26e6d8d0eb56c5c68771b52982e9aa5729c9c8f62c151b4145
[INFO] running `Command { std: "docker" "start" "-a" "9ce28049ba1f9f26e6d8d0eb56c5c68771b52982e9aa5729c9c8f62c151b4145", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9ce28049ba1f9f26e6d8d0eb56c5c68771b52982e9aa5729c9c8f62c151b4145", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9ce28049ba1f9f26e6d8d0eb56c5c68771b52982e9aa5729c9c8f62c151b4145", kill_on_drop: false }`
[INFO] [stdout] 9ce28049ba1f9f26e6d8d0eb56c5c68771b52982e9aa5729c9c8f62c151b4145
[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" "RUSTDOCFLAGS=--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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] aa3ccbd508eecfbc7e890efb40ba398afaaa42d5e1de938c2929ff508f2d067e
[INFO] running `Command { std: "docker" "start" "-a" "aa3ccbd508eecfbc7e890efb40ba398afaaa42d5e1de938c2929ff508f2d067e", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking isize-vec v0.1.1
[INFO] [stderr]  Documenting revent v0.29.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:63:12
[INFO] [stdout]    |
[INFO] [stdout] 63 | #![feature(coerce_unsized, drain_filter, unsize)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:63:28
[INFO] [stdout]    |
[INFO] [stdout] 63 | #![feature(coerce_unsized, drain_filter, unsize)]
[INFO] [stdout]    |                            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:63:42
[INFO] [stdout]    |
[INFO] [stdout] 63 | #![feature(coerce_unsized, drain_filter, unsize)]
[INFO] [stdout]    |                                          ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `revent`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name revent src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=f5369115def281de -L dependency=/opt/rustwide/target/debug/deps --extern isize_vec=/opt/rustwide/target/debug/deps/libisize_vec-aca9fb1e6cb0a82a.rmeta --cap-lints=warn --crate-version 0.29.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "aa3ccbd508eecfbc7e890efb40ba398afaaa42d5e1de938c2929ff508f2d067e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aa3ccbd508eecfbc7e890efb40ba398afaaa42d5e1de938c2929ff508f2d067e", kill_on_drop: false }`
[INFO] [stdout] aa3ccbd508eecfbc7e890efb40ba398afaaa42d5e1de938c2929ff508f2d067e