[INFO] cloning repository https://github.com/TopologicallySpeaking/ckproof
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/TopologicallySpeaking/ckproof" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTopologicallySpeaking%2Fckproof", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTopologicallySpeaking%2Fckproof'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b96af7cddc22c04936bb246be90caec98e06833a
[INFO] documenting TopologicallySpeaking/ckproof 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%2FTopologicallySpeaking%2Fckproof" "/workspace/builds/worker-14/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-14/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/TopologicallySpeaking/ckproof 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 git repo https://github.com/TopologicallySpeaking/ckproof
[INFO] finished tweaking git repo https://github.com/TopologicallySpeaking/ckproof
[INFO] tweaked toml for git repo https://github.com/TopologicallySpeaking/ckproof written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate git repo https://github.com/TopologicallySpeaking/ckproof 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]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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] 8c06e4fdabdaec66d2905912da5fddde5f39da76b915542d739797405e0a0f34
[INFO] running `Command { std: "docker" "start" "-a" "8c06e4fdabdaec66d2905912da5fddde5f39da76b915542d739797405e0a0f34", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8c06e4fdabdaec66d2905912da5fddde5f39da76b915542d739797405e0a0f34", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8c06e4fdabdaec66d2905912da5fddde5f39da76b915542d739797405e0a0f34", kill_on_drop: false }`
[INFO] [stdout] 8c06e4fdabdaec66d2905912da5fddde5f39da76b915542d739797405e0a0f34
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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] 966ea2beb188a0f7e707d886ad01738de9092c7306e27c16feaa6222458dd48b
[INFO] running `Command { std: "docker" "start" "-a" "966ea2beb188a0f7e707d886ad01738de9092c7306e27c16feaa6222458dd48b", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling syn v1.0.48
[INFO] [stderr]     Checking matches v0.1.8
[INFO] [stderr]    Compiling serde_derive v1.0.117
[INFO] [stderr]    Compiling ucd-trie v0.1.3
[INFO] [stderr]     Checking tinyvec_macros v0.1.0
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling maplit v1.0.2
[INFO] [stderr]    Compiling serde v1.0.117
[INFO] [stderr]    Compiling serde_json v1.0.59
[INFO] [stderr]     Checking percent-encoding v2.1.0
[INFO] [stderr]     Checking itoa v0.4.6
[INFO] [stderr]     Checking tinyvec v1.1.0
[INFO] [stderr]     Checking unicode-bidi v0.3.4
[INFO] [stderr]    Compiling pest v2.1.3
[INFO] [stderr]     Checking form_urlencoded v1.0.0
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]     Checking unicode-normalization v0.1.16
[INFO] [stderr]    Compiling pest_meta v2.1.3
[INFO] [stderr]     Checking idna v0.2.0
[INFO] [stderr]     Checking url v2.2.0
[INFO] [stderr]    Compiling pest_generator v2.1.3
[INFO] [stderr]    Compiling pest_derive v2.1.0
[INFO] [stderr]  Documenting ckproof 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:17:1
[INFO] [stdout]    |
[INFO] [stdout] 17 | #![feature(nll)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:18:1
[INFO] [stdout]    |
[INFO] [stdout] 18 | #![feature(once_cell)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 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 `ckproof`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name ckproof src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=5148f1100034f282 -L dependency=/opt/rustwide/target/debug/deps --extern pest=/opt/rustwide/target/debug/deps/libpest-ad621116ccc3017c.rmeta --extern pest_derive=/opt/rustwide/target/debug/deps/libpest_derive-745b696ad8eff650.so --extern serde=/opt/rustwide/target/debug/deps/libserde-f715ce11e6a79373.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-5ec786461f87858b.rmeta --extern url=/opt/rustwide/target/debug/deps/liburl-9c306add38ae221f.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "966ea2beb188a0f7e707d886ad01738de9092c7306e27c16feaa6222458dd48b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "966ea2beb188a0f7e707d886ad01738de9092c7306e27c16feaa6222458dd48b", kill_on_drop: false }`
[INFO] [stdout] 966ea2beb188a0f7e707d886ad01738de9092c7306e27c16feaa6222458dd48b