[INFO] fetching crate rifgen 0.1.51...
[INFO] documenting rifgen-0.1.51 against beta-2022-05-20 for beta-1.62-rustdoc-1
[INFO] extracting crate rifgen 0.1.51 into /workspace/builds/worker-39/source
[INFO] validating manifest of crates.io crate rifgen 0.1.51 on toolchain beta-2022-05-20
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-05-20" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate rifgen 0.1.51
[INFO] finished tweaking crates.io crate rifgen 0.1.51
[INFO] tweaked toml for crates.io crate rifgen 0.1.51 written to /workspace/builds/worker-39/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-05-20" "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-2022-05-20" "fetch" "--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-39/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-39/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" "+beta-2022-05-20" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 243779c5916844ce0662408b74c1030381aa85ee65e6be0cc37328bcdb5b9bf4
[INFO] running `Command { std: "docker" "start" "-a" "243779c5916844ce0662408b74c1030381aa85ee65e6be0cc37328bcdb5b9bf4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "243779c5916844ce0662408b74c1030381aa85ee65e6be0cc37328bcdb5b9bf4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "243779c5916844ce0662408b74c1030381aa85ee65e6be0cc37328bcdb5b9bf4", kill_on_drop: false }`
[INFO] [stdout] 243779c5916844ce0662408b74c1030381aa85ee65e6be0cc37328bcdb5b9bf4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-39/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-39/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" "+beta-2022-05-20" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1924654a852678f7452a599d76622c255c54f02cb7a4821003d274069af6481f
[INFO] running `Command { std: "docker" "start" "-a" "1924654a852678f7452a599d76622c255c54f02cb7a4821003d274069af6481f", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling unicode-ident v1.0.0
[INFO] [stderr]     Checking aho-corasick v0.7.18
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]     Checking regex v1.5.6
[INFO] [stderr]     Checking Inflector v0.11.4
[INFO] [stderr]    Compiling rifgen_attr v0.1.0
[INFO] [stderr]    Compiling derive-new v0.5.9
[INFO] [stderr]  Documenting rifgen v0.1.51 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(drain_filter)]
[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 document `rifgen`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name rifgen src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=7c2ee1db47e85149 -L dependency=/opt/rustwide/target/debug/deps --extern inflector=/opt/rustwide/target/debug/deps/libinflector-34813748eab24871.rmeta --extern derive_new=/opt/rustwide/target/debug/deps/libderive_new-6f8eab94fb22e379.so --extern rifgen_attr=/opt/rustwide/target/debug/deps/librifgen_attr-48b9c9cf7d0687c1.so --extern syn=/opt/rustwide/target/debug/deps/libsyn-74a40f61dc909e58.rmeta --cap-lints=warn --crate-version 0.1.51` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "1924654a852678f7452a599d76622c255c54f02cb7a4821003d274069af6481f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1924654a852678f7452a599d76622c255c54f02cb7a4821003d274069af6481f", kill_on_drop: false }`
[INFO] [stdout] 1924654a852678f7452a599d76622c255c54f02cb7a4821003d274069af6481f