[INFO] fetching crate librs 0.1.0...
[INFO] documenting librs-0.1.0 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate librs 0.1.0 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate librs 0.1.0 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate librs 0.1.0
[INFO] finished tweaking crates.io crate librs 0.1.0
[INFO] tweaked toml for crates.io crate librs 0.1.0 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", 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] 3c8a76462ea6a27697d0ffd96ade8435df17c039951419ed678810713289334b
[INFO] running `Command { std: "docker" "start" "-a" "3c8a76462ea6a27697d0ffd96ade8435df17c039951419ed678810713289334b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3c8a76462ea6a27697d0ffd96ade8435df17c039951419ed678810713289334b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3c8a76462ea6a27697d0ffd96ade8435df17c039951419ed678810713289334b", kill_on_drop: false }`
[INFO] [stdout] 3c8a76462ea6a27697d0ffd96ade8435df17c039951419ed678810713289334b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6571da0a66778f6b69aab42b39c23e8cd10ff9db2064cf0c9ba26bc5757c6e74
[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" "6571da0a66778f6b69aab42b39c23e8cd10ff9db2064cf0c9ba26bc5757c6e74", kill_on_drop: false }`
[INFO] [stderr]     Checking const_type v0.1.3
[INFO] [stderr]  Documenting librs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> source/lib.rs:12:1
[INFO] [stdout]    |
[INFO] [stdout] 12 | #![feature(asm)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> source/lib.rs:13:1
[INFO] [stdout]    |
[INFO] [stdout] 13 | #![feature(never_type)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[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 `librs`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name librs source/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern bitflags=/opt/rustwide/target/debug/deps/libbitflags-c759f8d07719039e.rmeta --extern const_type=/opt/rustwide/target/debug/deps/libconst_type-6fab434c2ed79071.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "6571da0a66778f6b69aab42b39c23e8cd10ff9db2064cf0c9ba26bc5757c6e74", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6571da0a66778f6b69aab42b39c23e8cd10ff9db2064cf0c9ba26bc5757c6e74", kill_on_drop: false }`
[INFO] [stdout] 6571da0a66778f6b69aab42b39c23e8cd10ff9db2064cf0c9ba26bc5757c6e74
