[INFO] fetching crate russh-agent 0.2.1...
[INFO] documenting russh-agent-0.2.1 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate russh-agent 0.2.1 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate russh-agent 0.2.1 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 russh-agent 0.2.1
[INFO] finished tweaking crates.io crate russh-agent 0.2.1
[INFO] tweaked toml for crates.io crate russh-agent 0.2.1 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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] [stdout] 2067b9106ec8b77f96799d23cc050dac50a87c48e25c2e6302b51225acae5206
[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" "2067b9106ec8b77f96799d23cc050dac50a87c48e25c2e6302b51225acae5206", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2067b9106ec8b77f96799d23cc050dac50a87c48e25c2e6302b51225acae5206", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2067b9106ec8b77f96799d23cc050dac50a87c48e25c2e6302b51225acae5206", kill_on_drop: false }`
[INFO] [stdout] 2067b9106ec8b77f96799d23cc050dac50a87c48e25c2e6302b51225acae5206
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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] ed2bd626eaf165fd53d93b2ee795887861100890ba18e426b83565b05828d381
[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" "ed2bd626eaf165fd53d93b2ee795887861100890ba18e426b83565b05828d381", kill_on_drop: false }`
[INFO] [stderr]    Compiling slog v2.5.2
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]    Compiling getset v0.1.1
[INFO] [stderr]     Checking slog-try v0.2.0
[INFO] [stderr]     Checking tokio v0.2.22
[INFO] [stderr]  Documenting russh-agent v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:18:1
[INFO] [stdout]    |
[INFO] [stdout] 18 | #![feature(async_closure, crate_visibility_modifier, error_iter)]
[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 `russh-agent`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name russh_agent 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 byteorder=/opt/rustwide/target/debug/deps/libbyteorder-af30f867a78f5aec.rmeta --extern bytes=/opt/rustwide/target/debug/deps/libbytes-e39cb00dc7b3284b.rmeta --extern getset=/opt/rustwide/target/debug/deps/libgetset-fb70d84d0b24d996.so --extern slog=/opt/rustwide/target/debug/deps/libslog-c811c49cd3d347f6.rmeta --extern slog_try=/opt/rustwide/target/debug/deps/libslog_try-f7a9b4436cd81870.rmeta --extern tokio=/opt/rustwide/target/debug/deps/libtokio-e81acbc575c7fbb1.rmeta --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "ed2bd626eaf165fd53d93b2ee795887861100890ba18e426b83565b05828d381", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ed2bd626eaf165fd53d93b2ee795887861100890ba18e426b83565b05828d381", kill_on_drop: false }`
[INFO] [stdout] ed2bd626eaf165fd53d93b2ee795887861100890ba18e426b83565b05828d381