[INFO] fetching crate assert_infrequent 0.1.0...
[INFO] documenting assert_infrequent-0.1.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate assert_infrequent 0.1.0 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate assert_infrequent 0.1.0 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 assert_infrequent 0.1.0
[INFO] finished tweaking crates.io crate assert_infrequent 0.1.0
[INFO] tweaked toml for crates.io crate assert_infrequent 0.1.0 written to /workspace/builds/worker-9/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-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] 0f1ec22bdace522d1328a1eec071e967a7fbdcc8b468741c728585563e89e88c
[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" "0f1ec22bdace522d1328a1eec071e967a7fbdcc8b468741c728585563e89e88c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0f1ec22bdace522d1328a1eec071e967a7fbdcc8b468741c728585563e89e88c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0f1ec22bdace522d1328a1eec071e967a7fbdcc8b468741c728585563e89e88c", kill_on_drop: false }`
[INFO] [stdout] 0f1ec22bdace522d1328a1eec071e967a7fbdcc8b468741c728585563e89e88c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] 6b2512db036a192c9e138afbd0cd07de7d9f6c2ea3b0149770e19d8b63e1840f
[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" "6b2512db036a192c9e138afbd0cd07de7d9f6c2ea3b0149770e19d8b63e1840f", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling cc v1.0.73
[INFO] [stderr]     Checking gimli v0.26.1
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking rustc-demangle v0.1.21
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking miniz_oxide v0.5.1
[INFO] [stderr]     Checking object v0.28.4
[INFO] [stderr]    Compiling backtrace v0.3.65
[INFO] [stderr]     Checking addr2line v0.17.0
[INFO] [stderr]  Documenting assert_infrequent 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:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![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 `assert_infrequent`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name assert_infrequent src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=03639edca68e98fd -L dependency=/opt/rustwide/target/debug/deps --extern backtrace=/opt/rustwide/target/debug/deps/libbacktrace-511694b3e54864c8.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-1479f2b7adeaa2b6.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "6b2512db036a192c9e138afbd0cd07de7d9f6c2ea3b0149770e19d8b63e1840f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b2512db036a192c9e138afbd0cd07de7d9f6c2ea3b0149770e19d8b63e1840f", kill_on_drop: false }`
[INFO] [stdout] 6b2512db036a192c9e138afbd0cd07de7d9f6c2ea3b0149770e19d8b63e1840f