[INFO] fetching crate nb-sync 0.2.0...
[INFO] documenting nb-sync-0.2.0 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate nb-sync 0.2.0 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate nb-sync 0.2.0 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 nb-sync 0.2.0
[INFO] finished tweaking crates.io crate nb-sync 0.2.0
[INFO] tweaked toml for crates.io crate nb-sync 0.2.0 written to /workspace/builds/worker-6/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] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] 21a2b25b1d2e8766d3ae425fbd3c8a0ed5c3b963cef65141db5b590435c251d6
[INFO] running `Command { std: "docker" "start" "-a" "21a2b25b1d2e8766d3ae425fbd3c8a0ed5c3b963cef65141db5b590435c251d6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "21a2b25b1d2e8766d3ae425fbd3c8a0ed5c3b963cef65141db5b590435c251d6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21a2b25b1d2e8766d3ae425fbd3c8a0ed5c3b963cef65141db5b590435c251d6", kill_on_drop: false }`
[INFO] [stdout] 21a2b25b1d2e8766d3ae425fbd3c8a0ed5c3b963cef65141db5b590435c251d6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] dcc309aec8f227edff970e97d2331af1b48c10ddf6d647f9af4d88621ba449cc
[INFO] running `Command { std: "docker" "start" "-a" "dcc309aec8f227edff970e97d2331af1b48c10ddf6d647f9af4d88621ba449cc", kill_on_drop: false }`
[INFO] [stderr]     Checking nb v1.0.0
[INFO] [stderr]    Compiling bare-metal v0.2.5
[INFO] [stderr]     Checking nb v0.1.3
[INFO] [stderr]  Documenting nb-sync v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> src/lib.rs:134:1
[INFO] [stdout]     |
[INFO] [stdout] 134 | #![feature(const_fn)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> src/lib.rs:135:1
[INFO] [stdout]     |
[INFO] [stdout] 135 | #![feature(optin_builtin_traits)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> src/lib.rs:136:1
[INFO] [stdout]     |
[INFO] [stdout] 136 | #![feature(never_type)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/fifo.rs:205:25
[INFO] [stdout]     |
[INFO] [stdout] 205 | impl<'a, 'b: 'a, T: 'b> !Sync for Receiver<'a, 'b, T> {
[INFO] [stdout]     |                         ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/fifo.rs:264:25
[INFO] [stdout]     |
[INFO] [stdout] 264 | impl<'a, 'b: 'a, T: 'b> !Sync for Sender<'a, 'b, T> {
[INFO] [stdout]     |                         ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: Could not document `nb-sync`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name nb_sync 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 bare_metal=/opt/rustwide/target/debug/deps/libbare_metal-54544eeeab6e3c2e.rmeta --extern nb=/opt/rustwide/target/debug/deps/libnb-6c6f6262830af367.rmeta --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "dcc309aec8f227edff970e97d2331af1b48c10ddf6d647f9af4d88621ba449cc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dcc309aec8f227edff970e97d2331af1b48c10ddf6d647f9af4d88621ba449cc", kill_on_drop: false }`
[INFO] [stdout] dcc309aec8f227edff970e97d2331af1b48c10ddf6d647f9af4d88621ba449cc