[INFO] fetching crate rcc4r 0.1.0...
[INFO] documenting rcc4r-0.1.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate rcc4r 0.1.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate rcc4r 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 rcc4r 0.1.0
[INFO] finished tweaking crates.io crate rcc4r 0.1.0
[INFO] tweaked toml for crates.io crate rcc4r 0.1.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate rcc4r 0.1.0 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] 951067f57c52de3ea13432ae504e7aa51b33907f6674aafdd356123601ae0cf5
[INFO] running `Command { std: "docker" "start" "-a" "951067f57c52de3ea13432ae504e7aa51b33907f6674aafdd356123601ae0cf5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "951067f57c52de3ea13432ae504e7aa51b33907f6674aafdd356123601ae0cf5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "951067f57c52de3ea13432ae504e7aa51b33907f6674aafdd356123601ae0cf5", kill_on_drop: false }`
[INFO] [stdout] 951067f57c52de3ea13432ae504e7aa51b33907f6674aafdd356123601ae0cf5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] 5656c361fc583a7908bdc895eb4fcb332e2b7b8733e10d919a7e7fa25b54fb63
[INFO] running `Command { std: "docker" "start" "-a" "5656c361fc583a7908bdc895eb4fcb332e2b7b8733e10d919a7e7fa25b54fb63", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.74
[INFO] [stderr]  Documenting rcc4r 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:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(ptr_wrapping_offset_from)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `ptr_wrapping_offset_from`
[INFO] [stdout]  --> src/main.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(ptr_wrapping_offset_from)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `rcc4r`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name rcc4r src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=bf821f9e1df7fffc -L dependency=/opt/rustwide/target/debug/deps --extern libc=/opt/rustwide/target/debug/deps/liblibc-1d5365383565f530.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "5656c361fc583a7908bdc895eb4fcb332e2b7b8733e10d919a7e7fa25b54fb63", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5656c361fc583a7908bdc895eb4fcb332e2b7b8733e10d919a7e7fa25b54fb63", kill_on_drop: false }`
[INFO] [stdout] 5656c361fc583a7908bdc895eb4fcb332e2b7b8733e10d919a7e7fa25b54fb63