[INFO] fetching crate futures-async-combinators 0.3.2...
[INFO] documenting futures-async-combinators-0.3.2 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate futures-async-combinators 0.3.2 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate futures-async-combinators 0.3.2 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 futures-async-combinators 0.3.2
[INFO] finished tweaking crates.io crate futures-async-combinators 0.3.2
[INFO] tweaked toml for crates.io crate futures-async-combinators 0.3.2 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate crates.io crate futures-async-combinators 0.3.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] 87e3e46f242b86a2b8e919b74d621ee2e8afc8a5f9a1f0c7a4ff95e31711328c
[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" "87e3e46f242b86a2b8e919b74d621ee2e8afc8a5f9a1f0c7a4ff95e31711328c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "87e3e46f242b86a2b8e919b74d621ee2e8afc8a5f9a1f0c7a4ff95e31711328c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "87e3e46f242b86a2b8e919b74d621ee2e8afc8a5f9a1f0c7a4ff95e31711328c", kill_on_drop: false }`
[INFO] [stdout] 87e3e46f242b86a2b8e919b74d621ee2e8afc8a5f9a1f0c7a4ff95e31711328c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] [stdout] d7254852b166b89f6983b24b9e7bce412f2589b4b3f01204768c95331dab56d1
[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" "d7254852b166b89f6983b24b9e7bce412f2589b4b3f01204768c95331dab56d1", kill_on_drop: false }`
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.19
[INFO] [stderr]  Documenting futures-async-combinators v0.3.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(async_closure, gen_future, generators)]
[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 `futures-async-combinators`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name futures_async_combinators src/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 futures_core=/opt/rustwide/target/debug/deps/libfutures_core-a4bc2c6bc523a37f.rmeta --extern pin_utils=/opt/rustwide/target/debug/deps/libpin_utils-d806f88ccd02f709.rmeta --cap-lints=warn --crate-version 0.3.2` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "d7254852b166b89f6983b24b9e7bce412f2589b4b3f01204768c95331dab56d1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d7254852b166b89f6983b24b9e7bce412f2589b4b3f01204768c95331dab56d1", kill_on_drop: false }`
[INFO] [stdout] d7254852b166b89f6983b24b9e7bce412f2589b4b3f01204768c95331dab56d1