[INFO] fetching crate epics-sys 0.0.5...
[INFO] documenting epics-sys-0.0.5 against 1.75.0 for beta-1.76-rustdoc-1
[INFO] extracting crate epics-sys 0.0.5 into /workspace/builds/worker-2-tc1/source
[INFO] validating manifest of crates.io crate epics-sys 0.0.5 on toolchain 1.75.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate epics-sys 0.0.5
[INFO] finished tweaking crates.io crate epics-sys 0.0.5
[INFO] tweaked toml for crates.io crate epics-sys 0.0.5 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" "+1.75.0" "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" "+1.75.0" "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" "+1.75.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 052393e0d6dd63be7858de8331c1d7f03edb5d3b4ad48ecc07c344cc95a7a754
[INFO] running `Command { std: "docker" "start" "-a" "052393e0d6dd63be7858de8331c1d7f03edb5d3b4ad48ecc07c344cc95a7a754", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "052393e0d6dd63be7858de8331c1d7f03edb5d3b4ad48ecc07c344cc95a7a754", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "052393e0d6dd63be7858de8331c1d7f03edb5d3b4ad48ecc07c344cc95a7a754", kill_on_drop: false }`
[INFO] [stdout] 052393e0d6dd63be7858de8331c1d7f03edb5d3b4ad48ecc07c344cc95a7a754
[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" "+1.75.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 961e560c22fb94994b49a7e21fcdc158dc8fd2070926a623f1edd340873f984f
[INFO] running `Command { std: "docker" "start" "-a" "961e560c22fb94994b49a7e21fcdc158dc8fd2070926a623f1edd340873f984f", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]     Checking unicode-xid v0.1.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking quote v0.6.13
[INFO] [stderr]  Documenting epics-sys v0.0.5 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(extern_crate_item_prelude)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `extern_crate_item_prelude` has been stable since `1.31.0` and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(concat_idents)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[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 `epics-sys`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/rustup-home/toolchains/1.75.0-x86_64-unknown-linux-gnu/bin/rustdoc --edition=2018 --crate-type proc-macro --crate-name epics_sys src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=1a39c321015502bb -L dependency=/opt/rustwide/target/debug/deps --extern proc_macro2=/opt/rustwide/target/debug/deps/libproc_macro2-c59054d75ea39f73.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-898769d2fa2038f0.rmeta --extern syn=/opt/rustwide/target/debug/deps/libsyn-61a395d743e069aa.rmeta --extern proc_macro --cap-lints=warn --crate-version 0.0.5` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "961e560c22fb94994b49a7e21fcdc158dc8fd2070926a623f1edd340873f984f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "961e560c22fb94994b49a7e21fcdc158dc8fd2070926a623f1edd340873f984f", kill_on_drop: false }`
[INFO] [stdout] 961e560c22fb94994b49a7e21fcdc158dc8fd2070926a623f1edd340873f984f
