[INFO] fetching crate shell-hooks 0.1.2...
[INFO] documenting shell-hooks-0.1.2 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate shell-hooks 0.1.2 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate shell-hooks 0.1.2 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 shell-hooks 0.1.2
[INFO] finished tweaking crates.io crate shell-hooks 0.1.2
[INFO] tweaked toml for crates.io crate shell-hooks 0.1.2 written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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] c563d9e30ba8cc13d5e9dc6e5593324967fca806c2e3f39d47fbb56edaa34d90
[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" "c563d9e30ba8cc13d5e9dc6e5593324967fca806c2e3f39d47fbb56edaa34d90", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c563d9e30ba8cc13d5e9dc6e5593324967fca806c2e3f39d47fbb56edaa34d90", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c563d9e30ba8cc13d5e9dc6e5593324967fca806c2e3f39d47fbb56edaa34d90", kill_on_drop: false }`
[INFO] [stdout] c563d9e30ba8cc13d5e9dc6e5593324967fca806c2e3f39d47fbb56edaa34d90
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] f9668c317f1f78092229943ef3f29cd023db1ef148950ad74594dfeb08996f97
[INFO] running `Command { std: "docker" "start" "-a" "f9668c317f1f78092229943ef3f29cd023db1ef148950ad74594dfeb08996f97", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling unicode-ident v1.0.0
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]    Compiling serde v1.0.137
[INFO] [stderr]     Checking vec_map v0.8.2
[INFO] [stderr]     Checking bitflags v1.3.2
[INFO] [stderr]    Compiling serde_derive v1.0.137
[INFO] [stderr]    Compiling structopt-derive v0.2.18
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking dirs v1.0.5
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]     Checking clap v2.34.0
[INFO] [stderr]     Checking structopt v0.2.18
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]  Documenting shell-hooks v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/bin/shell-hooks.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(vec_remove_item)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `vec_remove_item`
[INFO] [stdout]  --> src/bin/shell-hooks.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(vec_remove_item)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `shell-hooks`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name shell_hooks src/bin/shell-hooks.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=bc88ed1e413935cb -L dependency=/opt/rustwide/target/debug/deps --extern dirs=/opt/rustwide/target/debug/deps/libdirs-8add61b861656b3a.rmeta --extern libc=/opt/rustwide/target/debug/deps/liblibc-4e90763dd2291129.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-495ec9fdc6b7531e.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-83f91e0782093c72.so --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-ac206153211c5511.rmeta --extern toml=/opt/rustwide/target/debug/deps/libtoml-ac50d8fbccabdf89.rmeta --extern walkdir=/opt/rustwide/target/debug/deps/libwalkdir-aa60abb9fe6cfa5b.rmeta --cap-lints=warn --crate-version 0.1.2` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "f9668c317f1f78092229943ef3f29cd023db1ef148950ad74594dfeb08996f97", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f9668c317f1f78092229943ef3f29cd023db1ef148950ad74594dfeb08996f97", kill_on_drop: false }`
[INFO] [stdout] f9668c317f1f78092229943ef3f29cd023db1ef148950ad74594dfeb08996f97