[INFO] fetching crate dumbnet 0.1.0...
[INFO] documenting dumbnet-0.1.0 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate dumbnet 0.1.0 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate dumbnet 0.1.0 on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate dumbnet 0.1.0
[INFO] finished tweaking crates.io crate dumbnet 0.1.0
[INFO] tweaked toml for crates.io crate dumbnet 0.1.0 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate crates.io crate dumbnet 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "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-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+1.46.0" "metadata" "--no-deps" "--format-version=1", 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] 8cee929815401764f3fd58425b80099359ca76191c4c485ac86e5eda9ba67b38
[INFO] running `Command { std: "docker" "start" "-a" "8cee929815401764f3fd58425b80099359ca76191c4c485ac86e5eda9ba67b38", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8cee929815401764f3fd58425b80099359ca76191c4c485ac86e5eda9ba67b38", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8cee929815401764f3fd58425b80099359ca76191c4c485ac86e5eda9ba67b38", kill_on_drop: false }`
[INFO] [stdout] 8cee929815401764f3fd58425b80099359ca76191c4c485ac86e5eda9ba67b38
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6d45818e96ad93c460943a01b942057c51bff07b35e27f223d6bd1856f8fa1cd
[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" "6d45818e96ad93c460943a01b942057c51bff07b35e27f223d6bd1856f8fa1cd", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling getrandom v0.1.13
[INFO] [stderr]    Compiling typenum v1.11.2
[INFO] [stderr]     Checking ppv-lite86 v0.2.6
[INFO] [stderr]    Compiling syn v1.0.11
[INFO] [stderr]    Compiling num-traits v0.2.10
[INFO] [stderr]     Checking itertools v0.8.2
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking c2-chacha v0.2.3
[INFO] [stderr]     Checking generic-array v0.13.2
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking rand v0.7.2
[INFO] [stderr]     Checking numeric-array v0.4.2
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]  Documenting dumbnet v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![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 `dumbnet`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name dumbnet 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 generic_array=/opt/rustwide/target/debug/deps/libgeneric_array-0e21802ef24b049b.rmeta --extern getrandom=/opt/rustwide/target/debug/deps/libgetrandom-a5351ecad7136130.rmeta --extern itertools=/opt/rustwide/target/debug/deps/libitertools-f2cfd5e7c6f8f84c.rmeta --extern numeric_array=/opt/rustwide/target/debug/deps/libnumeric_array-d633e9eeb1b762fb.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-a7a37c06d55f53a9.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-ad08fc17c2d1843f.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-5d20462a9fa1113f.so --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "6d45818e96ad93c460943a01b942057c51bff07b35e27f223d6bd1856f8fa1cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6d45818e96ad93c460943a01b942057c51bff07b35e27f223d6bd1856f8fa1cd", kill_on_drop: false }`
[INFO] [stdout] 6d45818e96ad93c460943a01b942057c51bff07b35e27f223d6bd1856f8fa1cd