[INFO] cloning repository https://github.com/spacekookie/thunder
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/spacekookie/thunder" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspacekookie%2Fthunder", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspacekookie%2Fthunder'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 65bf4bca66a11b68d7ac94e9c5036f48f983fd02
[INFO] documenting spacekookie/thunder against 1.47.0 for beta-1.48-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspacekookie%2Fthunder" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/spacekookie/thunder on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/spacekookie/thunder
[INFO] finished tweaking git repo https://github.com/spacekookie/thunder
[INFO] tweaked toml for git repo https://github.com/spacekookie/thunder written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/spacekookie/thunder already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d971e377ed751770fb7006c95a8811f3922b404372c7f555449bc0f31b3efceb
[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" "d971e377ed751770fb7006c95a8811f3922b404372c7f555449bc0f31b3efceb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d971e377ed751770fb7006c95a8811f3922b404372c7f555449bc0f31b3efceb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d971e377ed751770fb7006c95a8811f3922b404372c7f555449bc0f31b3efceb", kill_on_drop: false }`
[INFO] [stdout] d971e377ed751770fb7006c95a8811f3922b404372c7f555449bc0f31b3efceb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "+1.47.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] c3ebe0fb8020ec77ba67cd89b07e7739be72ff2f752295bed3189faeba923477
[INFO] running `Command { std: "docker" "start" "-a" "c3ebe0fb8020ec77ba67cd89b07e7739be72ff2f752295bed3189faeba923477", kill_on_drop: false }`
[INFO] [stderr]     Checking proc-macro2 v0.2.3
[INFO] [stderr]     Checking textwrap v0.9.0
[INFO] [stderr]     Checking atty v0.2.10
[INFO] [stderr]     Checking clap v2.31.2
[INFO] [stderr]     Checking quote v0.4.2
[INFO] [stderr]     Checking syn v0.12.15
[INFO] [stderr]  Documenting thunder v0.3.1 (/opt/rustwide/workdir)
[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(external_doc)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(proc_macro, proc_macro_lib, iterator_flatten)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 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 `thunder`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type proc-macro --crate-name thunder 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 clap=/opt/rustwide/target/debug/deps/libclap-20e8c4e7fbb1e6aa.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-d2b3fe3bfefd110e.rmeta --extern syn=/opt/rustwide/target/debug/deps/libsyn-c803c9412ac2edd6.rmeta --extern proc_macro --cap-lints=warn --crate-version 0.3.1` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "c3ebe0fb8020ec77ba67cd89b07e7739be72ff2f752295bed3189faeba923477", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c3ebe0fb8020ec77ba67cd89b07e7739be72ff2f752295bed3189faeba923477", kill_on_drop: false }`
[INFO] [stdout] c3ebe0fb8020ec77ba67cd89b07e7739be72ff2f752295bed3189faeba923477
