[INFO] fetching crate thread_spawn 0.4.0...
[INFO] documenting thread_spawn-0.4.0 against 1.76.0 for beta-1.77-rustdoc-1
[INFO] extracting crate thread_spawn 0.4.0 into /workspace/builds/worker-7-tc1/source
[INFO] validating manifest of crates.io crate thread_spawn 0.4.0 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] removed /workspace/builds/worker-7-tc1/source/rust-toolchain
[INFO] started tweaking crates.io crate thread_spawn 0.4.0
[INFO] finished tweaking crates.io crate thread_spawn 0.4.0
[INFO] tweaked toml for crates.io crate thread_spawn 0.4.0 written to /workspace/builds/worker-7-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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tester v0.6.0
[INFO] [stderr]   Downloaded rustfix v0.4.6
[INFO] [stderr]   Downloaded compiletest_rs v0.3.26
[INFO] [stderr]   Downloaded syn v0.14.9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] 9a26c623e1a8aa221d9084891d89fc45c8614c19eee1d1d4197884262dea47a3
[INFO] running `Command { std: "docker" "start" "-a" "9a26c623e1a8aa221d9084891d89fc45c8614c19eee1d1d4197884262dea47a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9a26c623e1a8aa221d9084891d89fc45c8614c19eee1d1d4197884262dea47a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9a26c623e1a8aa221d9084891d89fc45c8614c19eee1d1d4197884262dea47a3", kill_on_drop: false }`
[INFO] [stdout] 9a26c623e1a8aa221d9084891d89fc45c8614c19eee1d1d4197884262dea47a3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] e6df03163726dab1066ede762fafc5ee5658fcb76584156f26712dc345081d0b
[INFO] running `Command { std: "docker" "start" "-a" "e6df03163726dab1066ede762fafc5ee5658fcb76584156f26712dc345081d0b", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]     Checking unicode-xid v0.1.0
[INFO] [stderr]     Checking quote v0.6.13
[INFO] [stderr]     Checking syn v0.14.9
[INFO] [stderr]  Documenting thread_spawn v0.4.0 (/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(proc_macro)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `proc_macro` has been stable since `1.29.0` 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 `thread_spawn`
[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 --crate-type proc-macro --crate-name thread_spawn src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=0fcb919b8ed66a5b -L dependency=/opt/rustwide/target/debug/deps --extern proc_macro2=/opt/rustwide/target/debug/deps/libproc_macro2-e86c7168891d9c60.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-d7e5e8411da41f13.rmeta --extern syn=/opt/rustwide/target/debug/deps/libsyn-53c436d0cdf97655.rmeta --extern proc_macro --cap-lints=warn --crate-version 0.4.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "e6df03163726dab1066ede762fafc5ee5658fcb76584156f26712dc345081d0b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e6df03163726dab1066ede762fafc5ee5658fcb76584156f26712dc345081d0b", kill_on_drop: false }`
[INFO] [stdout] e6df03163726dab1066ede762fafc5ee5658fcb76584156f26712dc345081d0b
