[INFO] fetching crate directory-tree 0.0.1...
[INFO] documenting directory-tree-0.0.1 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate directory-tree 0.0.1 into /workspace/builds/worker-105/source
[INFO] validating manifest of crates.io crate directory-tree 0.0.1 on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "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-105/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded cslice v0.2.0
[INFO] [stderr]   Downloaded neon-runtime v0.8.3
[INFO] [stderr]   Downloaded neon-build v0.8.3
[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-105/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-105/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7605469b69b97ed137ea2b79808c1828f881c733f05056d80e9da3160dbdf2a8
[INFO] running `Command { std: "docker" "start" "-a" "7605469b69b97ed137ea2b79808c1828f881c733f05056d80e9da3160dbdf2a8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7605469b69b97ed137ea2b79808c1828f881c733f05056d80e9da3160dbdf2a8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7605469b69b97ed137ea2b79808c1828f881c733f05056d80e9da3160dbdf2a8", kill_on_drop: false }`
[INFO] [stdout] 7605469b69b97ed137ea2b79808c1828f881c733f05056d80e9da3160dbdf2a8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-105/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-105/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d3469b328eeaddbe9768a416c680fa200dbee83ddda004f88b7b4b0318cba262
[INFO] running `Command { std: "docker" "start" "-a" "d3469b328eeaddbe9768a416c680fa200dbee83ddda004f88b7b4b0318cba262", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling unicode-ident v1.0.0
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]    Compiling neon-build v0.8.3
[INFO] [stderr]    Compiling serde_derive v1.0.137
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling serde v1.0.137
[INFO] [stderr]    Compiling serde_json v1.0.81
[INFO] [stderr]     Checking semver-parser v0.7.0
[INFO] [stderr]     Checking smallvec v1.8.0
[INFO] [stderr]     Checking cslice v0.2.0
[INFO] [stderr]     Checking itoa v1.0.2
[INFO] [stderr]     Checking ryu v1.0.10
[INFO] [stderr]     Checking libloading v0.6.7
[INFO] [stderr]     Checking semver v0.9.0
[INFO] [stderr]     Checking neon-runtime v0.8.3
[INFO] [stderr]    Compiling neon v0.8.3
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]    Compiling neon-macros 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: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not document `directory-tree`
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[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=747806bd1694dbd7 -L dependency=/opt/rustwide/target/debug/deps --extern neon=/opt/rustwide/target/debug/deps/libneon-9571c35909c6d80e.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-d4d6a9fe7dda36ea.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-58508c1119073e30.rmeta --cap-lints=warn --crate-version 0.0.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "d3469b328eeaddbe9768a416c680fa200dbee83ddda004f88b7b4b0318cba262", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d3469b328eeaddbe9768a416c680fa200dbee83ddda004f88b7b4b0318cba262", kill_on_drop: false }`
[INFO] [stdout] d3469b328eeaddbe9768a416c680fa200dbee83ddda004f88b7b4b0318cba262