[INFO] updating cached repository https://github.com/silversupreme/reckon
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1f31eb6ef6455b21d35fac53fbb4470315d5100f
[INFO] documenting silversupreme/reckon against master#394e1b40d264aa6928811919c1124fa248e7d802 for pr-73566
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsilversupreme%2Freckon" "/workspace/builds/worker-5/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/silversupreme/reckon on toolchain 394e1b40d264aa6928811919c1124fa248e7d802
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/silversupreme/reckon
[INFO] finished tweaking git repo https://github.com/silversupreme/reckon
[INFO] tweaked toml for git repo https://github.com/silversupreme/reckon written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/silversupreme/reckon already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "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] 718f30062a6f1a64339797d6b15d8afdbe3e211030f80f1ad011ac1a1a7048be
[INFO] running `Command { std: "docker" "start" "-a" "718f30062a6f1a64339797d6b15d8afdbe3e211030f80f1ad011ac1a1a7048be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "718f30062a6f1a64339797d6b15d8afdbe3e211030f80f1ad011ac1a1a7048be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "718f30062a6f1a64339797d6b15d8afdbe3e211030f80f1ad011ac1a1a7048be", kill_on_drop: false }`
[INFO] [stdout] 718f30062a6f1a64339797d6b15d8afdbe3e211030f80f1ad011ac1a1a7048be
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b29bcb7b9755f4b9d2ff0025c92a1f514ab94593c902e1db0d6d3d52d02f7d9c
[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" "b29bcb7b9755f4b9d2ff0025c92a1f514ab94593c902e1db0d6d3d52d02f7d9c", kill_on_drop: false }`
[INFO] [stderr]    Compiling winapi-build v0.1.1
[INFO] [stderr]     Checking winapi v0.2.8
[INFO] [stderr]     Checking memchr v0.1.11
[INFO] [stderr]     Checking aho-corasick v0.5.3
[INFO] [stderr]    Compiling kernel32-sys v0.2.2
[INFO] [stderr]     Checking thread-id v2.0.0
[INFO] [stderr]     Checking thread_local v0.2.7
[INFO] [stderr]     Checking regex v0.1.80
[INFO] [stderr]  Documenting reckon v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0635]: unknown feature `io`
[INFO] [stdout]  --> src/lib.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(io)]
[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 E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: Could not document `reckon`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name reckon 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 regex=/opt/rustwide/target/debug/deps/libregex-811d78b9784e69ec.rmeta --cap-lints=forbid` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "b29bcb7b9755f4b9d2ff0025c92a1f514ab94593c902e1db0d6d3d52d02f7d9c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b29bcb7b9755f4b9d2ff0025c92a1f514ab94593c902e1db0d6d3d52d02f7d9c", kill_on_drop: false }`
[INFO] [stdout] b29bcb7b9755f4b9d2ff0025c92a1f514ab94593c902e1db0d6d3d52d02f7d9c