[INFO] fetching crate rxrust 0.9.1...
[INFO] documenting rxrust-0.9.1 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate rxrust 0.9.1 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate rxrust 0.9.1 on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate rxrust 0.9.1
[INFO] finished tweaking crates.io crate rxrust 0.9.1
[INFO] tweaked toml for crates.io crate rxrust 0.9.1 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cd3d596a2fc22289ae522db269083f26471a7c724df1024fcbeba473f9e35dd1
[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" "cd3d596a2fc22289ae522db269083f26471a7c724df1024fcbeba473f9e35dd1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cd3d596a2fc22289ae522db269083f26471a7c724df1024fcbeba473f9e35dd1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cd3d596a2fc22289ae522db269083f26471a7c724df1024fcbeba473f9e35dd1", kill_on_drop: false }`
[INFO] [stdout] cd3d596a2fc22289ae522db269083f26471a7c724df1024fcbeba473f9e35dd1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+beta-2020-08-29" "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] fdee299f4c57c2c2f057790aae9286da8865596244a54b21f7ad20ffa40088ce
[INFO] running `Command { std: "docker" "start" "-a" "fdee299f4c57c2c2f057790aae9286da8865596244a54b21f7ad20ffa40088ce", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.39
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]     Checking once_cell v1.4.1
[INFO] [stderr]     Checking futures-io v0.3.5
[INFO] [stderr]     Checking futures-channel v0.3.5
[INFO] [stderr]     Checking async-channel v1.4.1
[INFO] [stderr]     Checking futures-task v0.3.5
[INFO] [stderr]     Checking futures-lite v0.1.11
[INFO] [stderr]     Checking polling v0.1.7
[INFO] [stderr]     Checking kv-log-macro v1.0.7
[INFO] [stderr]     Checking blocking v0.5.2
[INFO] [stderr]     Checking async-io v0.1.11
[INFO] [stderr]     Checking async-executor v0.1.2
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.67
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.67
[INFO] [stderr]    Compiling pin-project-internal v0.4.23
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.67
[INFO] [stderr]     Checking wasm-bindgen v0.2.67
[INFO] [stderr]     Checking js-sys v0.3.44
[INFO] [stderr]     Checking pin-project v0.4.23
[INFO] [stderr]     Checking futures-util v0.3.5
[INFO] [stderr]     Checking web-sys v0.3.44
[INFO] [stderr]     Checking futures-executor v0.3.5
[INFO] [stderr]     Checking futures v0.3.5
[INFO] [stderr]     Checking gloo-timers v0.2.1
[INFO] [stderr]     Checking futures-timer v3.0.2
[INFO] [stderr]     Checking async-std v1.6.3
[INFO] [stderr]  Documenting rxrust v0.9.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:2:1
[INFO] [stdout]    |
[INFO] [stdout] 2  | / #![feature(
[INFO] [stdout] 3  | |   external_doc,
[INFO] [stdout] 4  | |   min_specialization,
[INFO] [stdout] 5  | |   drain_filter,
[INFO] [stdout] ...  |
[INFO] [stdout] 9  | |   generic_associated_types
[INFO] [stdout] 10 | | )]
[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 `rxrust`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name rxrust src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --cfg 'feature="futures-scheduler"' --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern async_std=/opt/rustwide/target/debug/deps/libasync_std-26c54b31d4571ba6.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-1e7310a05b1c487b.rmeta --extern smallvec=/opt/rustwide/target/debug/deps/libsmallvec-44741354b26b7f09.rmeta --cap-lints=warn --crate-version 0.9.1` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "fdee299f4c57c2c2f057790aae9286da8865596244a54b21f7ad20ffa40088ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fdee299f4c57c2c2f057790aae9286da8865596244a54b21f7ad20ffa40088ce", kill_on_drop: false }`
[INFO] [stdout] fdee299f4c57c2c2f057790aae9286da8865596244a54b21f7ad20ffa40088ce