[INFO] fetching crate observatory 0.1.7...
[INFO] documenting observatory-0.1.7 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate observatory 0.1.7 into /workspace/builds/worker-26/source
[INFO] validating manifest of crates.io crate observatory 0.1.7 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 observatory 0.1.7
[INFO] finished tweaking crates.io crate observatory 0.1.7
[INFO] tweaked toml for crates.io crate observatory 0.1.7 written to /workspace/builds/worker-26/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]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-26/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-26/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] b2f2986dc024adbe246829f301a2d93493fe823a6abb4c62185eb41fe034b47d
[INFO] running `Command { std: "docker" "start" "-a" "b2f2986dc024adbe246829f301a2d93493fe823a6abb4c62185eb41fe034b47d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b2f2986dc024adbe246829f301a2d93493fe823a6abb4c62185eb41fe034b47d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b2f2986dc024adbe246829f301a2d93493fe823a6abb4c62185eb41fe034b47d", kill_on_drop: false }`
[INFO] [stdout] b2f2986dc024adbe246829f301a2d93493fe823a6abb4c62185eb41fe034b47d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-26/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-26/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] 0df6cd6ec6ccd27987ba941ccbf9c48fa2326e13c778ac4cd30e06c03737edf0
[INFO] running `Command { std: "docker" "start" "-a" "0df6cd6ec6ccd27987ba941ccbf9c48fa2326e13c778ac4cd30e06c03737edf0", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.8
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling crossbeam-queue v0.3.5
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling memoffset v0.6.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.8
[INFO] [stderr]     Checking crossbeam-channel v0.5.4
[INFO] [stderr]     Checking crossbeam-deque v0.8.1
[INFO] [stderr]     Checking crossbeam v0.8.1
[INFO] [stderr]  Documenting observatory v0.1.7 (/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(arc_new_cyclic)]
[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:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(unsize)]
[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:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(coerce_unsized)]
[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:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(test)]
[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:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(min_specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[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] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `observatory`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name observatory src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=3114620730776e39 -L dependency=/opt/rustwide/target/debug/deps --extern crossbeam=/opt/rustwide/target/debug/deps/libcrossbeam-c4a0055750f3a228.rmeta --extern crossbeam_utils=/opt/rustwide/target/debug/deps/libcrossbeam_utils-ee7e8a5782bb99c0.rmeta --cap-lints=warn --crate-version 0.1.7` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "0df6cd6ec6ccd27987ba941ccbf9c48fa2326e13c778ac4cd30e06c03737edf0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0df6cd6ec6ccd27987ba941ccbf9c48fa2326e13c778ac4cd30e06c03737edf0", kill_on_drop: false }`
[INFO] [stdout] 0df6cd6ec6ccd27987ba941ccbf9c48fa2326e13c778ac4cd30e06c03737edf0