[INFO] fetching crate macsmc 0.1.7...
[INFO] documenting macsmc-0.1.7 against 1.75.0 for beta-1.76-rustdoc-1
[INFO] extracting crate macsmc 0.1.7 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate macsmc 0.1.7 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 macsmc 0.1.7
[INFO] finished tweaking crates.io crate macsmc 0.1.7
[INFO] tweaked toml for crates.io crate macsmc 0.1.7 written to /workspace/builds/worker-4-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-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 7169fc37d0bdc85094ee576ba792b3f05295a0d9c7304e262298274206c13790
[INFO] running `Command { std: "docker" "start" "-a" "7169fc37d0bdc85094ee576ba792b3f05295a0d9c7304e262298274206c13790", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7169fc37d0bdc85094ee576ba792b3f05295a0d9c7304e262298274206c13790", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7169fc37d0bdc85094ee576ba792b3f05295a0d9c7304e262298274206c13790", kill_on_drop: false }`
[INFO] [stdout] 7169fc37d0bdc85094ee576ba792b3f05295a0d9c7304e262298274206c13790
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 0b4b9fd57b25b57ef1b42d57d9c15df0ed7cb8815af9ddad1b55920d096ad627
[INFO] running `Command { std: "docker" "start" "-a" "0b4b9fd57b25b57ef1b42d57d9c15df0ed7cb8815af9ddad1b55920d096ad627", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.151
[INFO] [stderr]  Documenting macsmc v0.1.7 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:27:18
[INFO] [stdout]    |
[INFO] [stdout] 27 | #![cfg_attr(doc, feature(doc_cfg))]
[INFO] [stdout]    |                  ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 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 `macsmc`
[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 lib --crate-name macsmc src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=ac833db124f4f5a4 -L dependency=/opt/rustwide/target/debug/deps --extern libc=/opt/rustwide/target/debug/deps/liblibc-d14b5e10944e99e9.rmeta --cap-lints=warn --crate-version 0.1.7` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "0b4b9fd57b25b57ef1b42d57d9c15df0ed7cb8815af9ddad1b55920d096ad627", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0b4b9fd57b25b57ef1b42d57d9c15df0ed7cb8815af9ddad1b55920d096ad627", kill_on_drop: false }`
[INFO] [stdout] 0b4b9fd57b25b57ef1b42d57d9c15df0ed7cb8815af9ddad1b55920d096ad627
