[INFO] fetching crate tree-automata 0.1.2...
[INFO] documenting tree-automata-0.1.2 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate tree-automata 0.1.2 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate tree-automata 0.1.2 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 tree-automata 0.1.2
[INFO] finished tweaking crates.io crate tree-automata 0.1.2
[INFO] tweaked toml for crates.io crate tree-automata 0.1.2 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate tree-automata 0.1.2 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] db5c6baff5ad898ab63234224e63ebbd79c4714189cebe4673fbae95a5e88fbb
[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" "db5c6baff5ad898ab63234224e63ebbd79c4714189cebe4673fbae95a5e88fbb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "db5c6baff5ad898ab63234224e63ebbd79c4714189cebe4673fbae95a5e88fbb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db5c6baff5ad898ab63234224e63ebbd79c4714189cebe4673fbae95a5e88fbb", kill_on_drop: false }`
[INFO] [stdout] db5c6baff5ad898ab63234224e63ebbd79c4714189cebe4673fbae95a5e88fbb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] 21ac8ef2e1fdc0a93083b7f531a8889d26529766e4d8fe6c4db9714afdf74a84
[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" "21ac8ef2e1fdc0a93083b7f531a8889d26529766e4d8fe6c4db9714afdf74a84", kill_on_drop: false }`
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]     Checking getrandom v0.1.14
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking crossbeam-channel v0.4.3
[INFO] [stderr]     Checking terms v0.1.2
[INFO] [stderr]  Documenting tree-automata v0.1.2 (/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] [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 `tree-automata`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name tree_automata 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 crossbeam_channel=/opt/rustwide/target/debug/deps/libcrossbeam_channel-2449d7dd126bd1c5.rmeta --extern terms=/opt/rustwide/target/debug/deps/libterms-38f29a6e11d50319.rmeta --cap-lints=warn --crate-version 0.1.2` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "21ac8ef2e1fdc0a93083b7f531a8889d26529766e4d8fe6c4db9714afdf74a84", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21ac8ef2e1fdc0a93083b7f531a8889d26529766e4d8fe6c4db9714afdf74a84", kill_on_drop: false }`
[INFO] [stdout] 21ac8ef2e1fdc0a93083b7f531a8889d26529766e4d8fe6c4db9714afdf74a84
