[INFO] fetching crate basic_allocator 0.1.6...
[INFO] documenting basic_allocator-0.1.6 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate basic_allocator 0.1.6 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate basic_allocator 0.1.6 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate basic_allocator 0.1.6
[INFO] finished tweaking crates.io crate basic_allocator 0.1.6
[INFO] tweaked toml for crates.io crate basic_allocator 0.1.6 written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate crates.io crate basic_allocator 0.1.6 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded sysconf v0.3.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 551392bf1bfdd08ae1fad147e8be2e34092857ae39d2422d2a258c3ed936bcb3
[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" "551392bf1bfdd08ae1fad147e8be2e34092857ae39d2422d2a258c3ed936bcb3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "551392bf1bfdd08ae1fad147e8be2e34092857ae39d2422d2a258c3ed936bcb3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "551392bf1bfdd08ae1fad147e8be2e34092857ae39d2422d2a258c3ed936bcb3", kill_on_drop: false }`
[INFO] [stdout] 551392bf1bfdd08ae1fad147e8be2e34092857ae39d2422d2a258c3ed936bcb3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f88980225d3c75d5af0ee6ca23b3bceb9bf9caa264a0dd56fa5e5a272563d142
[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" "f88980225d3c75d5af0ee6ca23b3bceb9bf9caa264a0dd56fa5e5a272563d142", kill_on_drop: false }`
[INFO] [stderr]  Documenting basic_allocator v0.1.6 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:40
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![cfg_attr(not(feature = "use_libc"), feature(asm))]
[INFO] [stdout]   |                                        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 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 `basic_allocator`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name basic_allocator src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern spin=/opt/rustwide/target/debug/deps/libspin-bc2864a2d95dabf7.rmeta --extern static_assertions=/opt/rustwide/target/debug/deps/libstatic_assertions-cb959170b4570325.rmeta --cap-lints=warn --crate-version 0.1.6` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "f88980225d3c75d5af0ee6ca23b3bceb9bf9caa264a0dd56fa5e5a272563d142", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f88980225d3c75d5af0ee6ca23b3bceb9bf9caa264a0dd56fa5e5a272563d142", kill_on_drop: false }`
[INFO] [stdout] f88980225d3c75d5af0ee6ca23b3bceb9bf9caa264a0dd56fa5e5a272563d142
