[INFO] fetching crate directory-tree 0.0.1...
[INFO] documenting directory-tree-0.0.1 against 1.69.0 for beta-1.70-rustdoc-1
[INFO] extracting crate directory-tree 0.0.1 into /workspace/builds/worker-6-tc1/source
[INFO] validating manifest of crates.io crate directory-tree 0.0.1 on toolchain 1.69.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.69.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate directory-tree 0.0.1
[INFO] finished tweaking crates.io crate directory-tree 0.0.1
[INFO] tweaked toml for crates.io crate directory-tree 0.0.1 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" __CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS="nightly" "/workspace/cargo-home/bin/cargo" "+1.69.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.69.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded neon-runtime v0.8.3
[INFO] [stderr]   Downloaded neon-build v0.8.3
[INFO] [stderr]   Downloaded cslice v0.2.0
[INFO] [stderr]   Downloaded neon-macros v0.8.3
[INFO] [stderr]   Downloaded neon v0.8.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 14bb9cfe0cc83b7f1add387e0d7ee1a8172e50e5956f9721ce9d3f4ced7324d4
[INFO] running `Command { std: "docker" "start" "-a" "14bb9cfe0cc83b7f1add387e0d7ee1a8172e50e5956f9721ce9d3f4ced7324d4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "14bb9cfe0cc83b7f1add387e0d7ee1a8172e50e5956f9721ce9d3f4ced7324d4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "14bb9cfe0cc83b7f1add387e0d7ee1a8172e50e5956f9721ce9d3f4ced7324d4", kill_on_drop: false }`
[INFO] [stdout] 14bb9cfe0cc83b7f1add387e0d7ee1a8172e50e5956f9721ce9d3f4ced7324d4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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" "RUSTFLAGS=--cap-lints=warn" "-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@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d74f37bc68a469352ed8b54a4e3886509e19921b5a55db32a7283d339a71363a
[INFO] running `Command { std: "docker" "start" "-a" "d74f37bc68a469352ed8b54a4e3886509e19921b5a55db32a7283d339a71363a", kill_on_drop: false }`
[INFO] [stderr]    Compiling neon-build v0.8.3
[INFO] [stderr]    Compiling serde_derive v1.0.160
[INFO] [stderr]    Compiling serde v1.0.160
[INFO] [stderr]     Checking smallvec v1.10.0
[INFO] [stderr]     Checking semver-parser v0.7.0
[INFO] [stderr]    Compiling serde_json v1.0.96
[INFO] [stderr]     Checking itoa v1.0.6
[INFO] [stderr]     Checking cslice v0.2.0
[INFO] [stderr]     Checking ryu v1.0.13
[INFO] [stderr]     Checking libloading v0.6.7
[INFO] [stderr]    Compiling syn v2.0.15
[INFO] [stderr]    Compiling neon-macros v0.8.3
[INFO] [stderr]     Checking semver v0.9.0
[INFO] [stderr]     Checking neon-runtime v0.8.3
[INFO] [stderr]    Compiling neon v0.8.3
[INFO] [stderr]  Documenting directory-tree v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(trait_alias)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `directory-tree`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type cdylib --crate-name directory_tree src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=c16ef54437e36a89 -L dependency=/opt/rustwide/target/debug/deps --extern neon=/opt/rustwide/target/debug/deps/libneon-d311d748b520f713.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-7f5aa0c9c57e86c5.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-9f766820a7671020.rmeta --cap-lints=warn --crate-version 0.0.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "d74f37bc68a469352ed8b54a4e3886509e19921b5a55db32a7283d339a71363a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d74f37bc68a469352ed8b54a4e3886509e19921b5a55db32a7283d339a71363a", kill_on_drop: false }`
[INFO] [stdout] d74f37bc68a469352ed8b54a4e3886509e19921b5a55db32a7283d339a71363a
