[INFO] fetching crate decimate 0.2.2...
[INFO] documenting decimate-0.2.2 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate decimate 0.2.2 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate decimate 0.2.2 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 decimate 0.2.2
[INFO] finished tweaking crates.io crate decimate 0.2.2
[INFO] tweaked toml for crates.io crate decimate 0.2.2 written to /workspace/builds/worker-3/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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 880c728d56fafc3666d13bb40973119840d9a4de07cf3b613bc12107c544c830
[INFO] running `Command { std: "docker" "start" "-a" "880c728d56fafc3666d13bb40973119840d9a4de07cf3b613bc12107c544c830", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "880c728d56fafc3666d13bb40973119840d9a4de07cf3b613bc12107c544c830", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "880c728d56fafc3666d13bb40973119840d9a4de07cf3b613bc12107c544c830", kill_on_drop: false }`
[INFO] [stdout] 880c728d56fafc3666d13bb40973119840d9a4de07cf3b613bc12107c544c830
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] c347a1944c6008fe75e2a0af20d8fe2cd092f50512be25f221a38e865712040d
[INFO] running `Command { std: "docker" "start" "-a" "c347a1944c6008fe75e2a0af20d8fe2cd092f50512be25f221a38e865712040d", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]     Checking rustc-serialize v0.3.24
[INFO] [stderr]     Checking serde v1.0.137
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]    Compiling num-iter v0.1.43
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking num-complex v0.1.43
[INFO] [stderr]     Checking num-bigint v0.1.44
[INFO] [stderr]     Checking num-rational v0.1.42
[INFO] [stderr]     Checking num v0.1.42
[INFO] [stderr]  Documenting decimate v0.2.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:26:12
[INFO] [stdout]    |
[INFO] [stdout] 26 | #![feature(test)]
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `decimate`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name decimate src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --cfg 'feature="serde"' --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=2e181b8b9faa8d3b -L dependency=/opt/rustwide/target/debug/deps --extern num=/opt/rustwide/target/debug/deps/libnum-9b0eef884018cb86.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-495ec9fdc6b7531e.rmeta --cap-lints=warn --crate-version 0.2.2` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "c347a1944c6008fe75e2a0af20d8fe2cd092f50512be25f221a38e865712040d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c347a1944c6008fe75e2a0af20d8fe2cd092f50512be25f221a38e865712040d", kill_on_drop: false }`
[INFO] [stdout] c347a1944c6008fe75e2a0af20d8fe2cd092f50512be25f221a38e865712040d