[INFO] fetching crate proper 0.1.5...
[INFO] documenting proper-0.1.5 against 1.76.0 for beta-1.77-rustdoc-1
[INFO] extracting crate proper 0.1.5 into /workspace/builds/worker-2-tc1/source
[INFO] validating manifest of crates.io crate proper 0.1.5 on toolchain 1.76.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate proper 0.1.5
[INFO] finished tweaking crates.io crate proper 0.1.5
[INFO] tweaked toml for crates.io crate proper 0.1.5 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.76.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bac6a29d7da05a056f43772be04b9925c27612ab1d8b2d1c5e4ba24499c44201
[INFO] running `Command { std: "docker" "start" "-a" "bac6a29d7da05a056f43772be04b9925c27612ab1d8b2d1c5e4ba24499c44201", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bac6a29d7da05a056f43772be04b9925c27612ab1d8b2d1c5e4ba24499c44201", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bac6a29d7da05a056f43772be04b9925c27612ab1d8b2d1c5e4ba24499c44201", kill_on_drop: false }`
[INFO] [stdout] bac6a29d7da05a056f43772be04b9925c27612ab1d8b2d1c5e4ba24499c44201
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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" "RUSTFLAGS=--cap-lints=warn" "-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.76.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c13bb37666b7be693ab516a52a0c89f1a29a131a2516b38c24d2b2f7acdbbb03
[INFO] running `Command { std: "docker" "start" "-a" "c13bb37666b7be693ab516a52a0c89f1a29a131a2516b38c24d2b2f7acdbbb03", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.78
[INFO] [stderr]     Checking quote v1.0.35
[INFO] [stderr]     Checking syn v1.0.109
[INFO] [stderr]  Documenting proper v0.1.5 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:66:1
[INFO] [stdout]    |
[INFO] [stdout] 66 | #![feature(bind_by_move_pattern_guards, proc_macro_diagnostic, proc_macro_span)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: the feature `bind_by_move_pattern_guards` has been stable since `1.39.0` and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 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 `proper`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/rustup-home/toolchains/1.76.0-x86_64-unknown-linux-gnu/bin/rustdoc --edition=2018 --crate-type proc-macro --crate-name proper src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=b50f87a515167802 -L dependency=/opt/rustwide/target/debug/deps --extern proc_macro2=/opt/rustwide/target/debug/deps/libproc_macro2-1bc556be54688c37.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-44762e16f83d10ff.rmeta --extern syn=/opt/rustwide/target/debug/deps/libsyn-a22b00ddb48554f8.rmeta --extern proc_macro --cap-lints=warn --crate-version 0.1.5` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "c13bb37666b7be693ab516a52a0c89f1a29a131a2516b38c24d2b2f7acdbbb03", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c13bb37666b7be693ab516a52a0c89f1a29a131a2516b38c24d2b2f7acdbbb03", kill_on_drop: false }`
[INFO] [stdout] c13bb37666b7be693ab516a52a0c89f1a29a131a2516b38c24d2b2f7acdbbb03
