[INFO] fetching crate interpolate 0.2.3...
[INFO] documenting interpolate-0.2.3 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate interpolate 0.2.3 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate interpolate 0.2.3 on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate interpolate 0.2.3
[INFO] finished tweaking crates.io crate interpolate 0.2.3
[INFO] tweaked toml for crates.io crate interpolate 0.2.3 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: library `interpolate` should only specify `proc-macro = true` instead of setting `crate-type`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8103ed5e9697cb8b2718fd241499115163ec3af24dc3dd1a5f8416c1edaac8cd
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "8103ed5e9697cb8b2718fd241499115163ec3af24dc3dd1a5f8416c1edaac8cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8103ed5e9697cb8b2718fd241499115163ec3af24dc3dd1a5f8416c1edaac8cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8103ed5e9697cb8b2718fd241499115163ec3af24dc3dd1a5f8416c1edaac8cd", kill_on_drop: false }`
[INFO] [stdout] 8103ed5e9697cb8b2718fd241499115163ec3af24dc3dd1a5f8416c1edaac8cd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b44401d26ea6051d6583e7ca9a65d2c87da914a5f68c98fbe686dfdb2528cabf
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "b44401d26ea6051d6583e7ca9a65d2c87da914a5f68c98fbe686dfdb2528cabf", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr] warning: library `interpolate` should only specify `proc-macro = true` instead of setting `crate-type`
[INFO] [stderr]  Documenting interpolate v0.2.3 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:18:1
[INFO] [stdout]    |
[INFO] [stdout] 18 | #![feature(proc_macro_hygiene, proc_macro_quote)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[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 `interpolate`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type proc-macro --crate-name interpolate src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern proc_macro --cap-lints=warn --crate-version 0.2.3` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "b44401d26ea6051d6583e7ca9a65d2c87da914a5f68c98fbe686dfdb2528cabf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b44401d26ea6051d6583e7ca9a65d2c87da914a5f68c98fbe686dfdb2528cabf", kill_on_drop: false }`
[INFO] [stdout] b44401d26ea6051d6583e7ca9a65d2c87da914a5f68c98fbe686dfdb2528cabf