[INFO] cloning repository https://github.com/CMIW/Simple_OS
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/CMIW/Simple_OS" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCMIW%2FSimple_OS", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCMIW%2FSimple_OS'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 47261f4758fd90f35d05b137d2ba93b1a2f61570
[INFO] documenting CMIW/Simple_OS against 1.61.0 for beta-1.62-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FCMIW%2FSimple_OS" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/CMIW/Simple_OS 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] removed /workspace/builds/worker-4/source/.cargo/config.toml
[INFO] removed /workspace/builds/worker-4/source/rust-toolchain
[INFO] started tweaking git repo https://github.com/CMIW/Simple_OS
[INFO] finished tweaking git repo https://github.com/CMIW/Simple_OS
[INFO] tweaked toml for git repo https://github.com/CMIW/Simple_OS written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/CMIW/Simple_OS already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded bootloader v0.9.22
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] c4fcb5cd14e3b90064085cae7a68e043426f4b2f0215e76572a42ab5f91dc063
[INFO] running `Command { std: "docker" "start" "-a" "c4fcb5cd14e3b90064085cae7a68e043426f4b2f0215e76572a42ab5f91dc063", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c4fcb5cd14e3b90064085cae7a68e043426f4b2f0215e76572a42ab5f91dc063", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c4fcb5cd14e3b90064085cae7a68e043426f4b2f0215e76572a42ab5f91dc063", kill_on_drop: false }`
[INFO] [stdout] c4fcb5cd14e3b90064085cae7a68e043426f4b2f0215e76572a42ab5f91dc063
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] b7a870e903d3948ddb98d9ce4cccc958a2f0fd005c8834077002a6bf765a3963
[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" "b7a870e903d3948ddb98d9ce4cccc958a2f0fd005c8834077002a6bf765a3963", kill_on_drop: false }`
[INFO] [stderr]    Compiling bootloader v0.9.22
[INFO] [stderr]     Checking volatile v0.2.7
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]  Documenting simple_os v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(custom_test_frameworks)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 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 `simple_os`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name simple_os src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=024238e8e30a7372 -L dependency=/opt/rustwide/target/debug/deps --extern bootloader=/opt/rustwide/target/debug/deps/libbootloader-6f0b3af66880b478.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-ed3ba279ce80868a.rmeta --extern spin=/opt/rustwide/target/debug/deps/libspin-f07759e3f4294fd6.rmeta --extern volatile=/opt/rustwide/target/debug/deps/libvolatile-256cf0a39cb7f25d.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "b7a870e903d3948ddb98d9ce4cccc958a2f0fd005c8834077002a6bf765a3963", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b7a870e903d3948ddb98d9ce4cccc958a2f0fd005c8834077002a6bf765a3963", kill_on_drop: false }`
[INFO] [stdout] b7a870e903d3948ddb98d9ce4cccc958a2f0fd005c8834077002a6bf765a3963