[INFO] fetching crate zerogc-simple 0.2.0-alpha.7...
[INFO] documenting zerogc-simple-0.2.0-alpha.7 against beta-2022-05-20 for beta-1.62-rustdoc-1
[INFO] extracting crate zerogc-simple 0.2.0-alpha.7 into /workspace/builds/worker-36/source
[INFO] validating manifest of crates.io crate zerogc-simple 0.2.0-alpha.7 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 zerogc-simple 0.2.0-alpha.7
[INFO] removed 0 missing tests
[INFO] finished tweaking crates.io crate zerogc-simple 0.2.0-alpha.7
[INFO] tweaked toml for crates.io crate zerogc-simple 0.2.0-alpha.7 written to /workspace/builds/worker-36/source/Cargo.toml
[INFO] crate crates.io crate zerogc-simple 0.2.0-alpha.7 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-05-20" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/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] da66c42066a71399a8b5006a219e5ca4868b5abb2c9bcfaf78b68b5418ae4de7
[INFO] running `Command { std: "docker" "start" "-a" "da66c42066a71399a8b5006a219e5ca4868b5abb2c9bcfaf78b68b5418ae4de7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "da66c42066a71399a8b5006a219e5ca4868b5abb2c9bcfaf78b68b5418ae4de7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da66c42066a71399a8b5006a219e5ca4868b5abb2c9bcfaf78b68b5418ae4de7", kill_on_drop: false }`
[INFO] [stdout] da66c42066a71399a8b5006a219e5ca4868b5abb2c9bcfaf78b68b5418ae4de7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/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] b10f1cdc30a74c80e7b8a389122609a1c527f6ffb86559ce07f36e389260000c
[INFO] running `Command { std: "docker" "start" "-a" "b10f1cdc30a74c80e7b8a389122609a1c527f6ffb86559ce07f36e389260000c", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.36
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.86
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling unicode-segmentation v1.9.0
[INFO] [stderr]    Compiling ident_case v1.0.1
[INFO] [stderr]    Compiling fnv v1.0.7
[INFO] [stderr]    Compiling strsim v0.10.0
[INFO] [stderr]    Compiling hashbrown v0.11.2
[INFO] [stderr]    Compiling libc v0.2.117
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling parking_lot_core v0.8.5
[INFO] [stderr]     Checking smallvec v1.8.0
[INFO] [stderr]    Compiling slog v2.7.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.7
[INFO] [stderr]     Checking bumpalo v3.9.1
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking once_cell v1.9.0
[INFO] [stderr]     Checking instant v0.1.12
[INFO] [stderr]     Checking lock_api v0.4.6
[INFO] [stderr]    Compiling itertools v0.10.3
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]    Compiling indexmap v1.8.0
[INFO] [stderr]    Compiling quote v1.0.15
[INFO] [stderr]     Checking parking_lot v0.11.2
[INFO] [stderr]    Compiling darling_core v0.13.1
[INFO] [stderr]    Compiling proc-macro-kwargs-derive v0.1.5
[INFO] [stderr]    Compiling darling_macro v0.13.1
[INFO] [stderr]    Compiling inherent v1.0.0
[INFO] [stderr]    Compiling darling v0.13.1
[INFO] [stderr]    Compiling proc-macro-kwargs v0.1.5
[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/proc-macro-kwargs-0.1.5/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(trait_alias)]
[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 `proc-macro-kwargs` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "b10f1cdc30a74c80e7b8a389122609a1c527f6ffb86559ce07f36e389260000c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b10f1cdc30a74c80e7b8a389122609a1c527f6ffb86559ce07f36e389260000c", kill_on_drop: false }`
[INFO] [stdout] b10f1cdc30a74c80e7b8a389122609a1c527f6ffb86559ce07f36e389260000c