[INFO] fetching crate pgc 0.3.0...
[INFO] documenting pgc-0.3.0 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate pgc 0.3.0 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate pgc 0.3.0 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 pgc 0.3.0
[INFO] finished tweaking crates.io crate pgc 0.3.0
[INFO] tweaked toml for crates.io crate pgc 0.3.0 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate crates.io crate pgc 0.3.0 already has a lockfile, it will not be regenerated
[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]  Downloading crates ...
[INFO] [stderr]   Downloaded mimalloc v0.1.9
[INFO] [stderr]   Downloaded libmimalloc-sys v0.1.6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] fe10072025a49b33e2b2852a1acc21a207214bcfce69be18c897e0f5ff6ce76d
[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" "fe10072025a49b33e2b2852a1acc21a207214bcfce69be18c897e0f5ff6ce76d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fe10072025a49b33e2b2852a1acc21a207214bcfce69be18c897e0f5ff6ce76d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fe10072025a49b33e2b2852a1acc21a207214bcfce69be18c897e0f5ff6ce76d", kill_on_drop: false }`
[INFO] [stdout] fe10072025a49b33e2b2852a1acc21a207214bcfce69be18c897e0f5ff6ce76d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] 849b339e2e1dbd5611ecf22b1ae5d4d98a377a76bc3e23d07cd418fafd439941
[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" "849b339e2e1dbd5611ecf22b1ae5d4d98a377a76bc3e23d07cd418fafd439941", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling cmake v0.1.42
[INFO] [stderr]     Checking threadpool v1.7.1
[INFO] [stderr]     Checking crossbeam-epoch v0.7.2
[INFO] [stderr]    Compiling libmimalloc-sys v0.1.6
[INFO] [stderr]     Checking crossbeam-deque v0.7.1
[INFO] [stderr]     Checking mimalloc v0.1.9
[INFO] [stderr]  Documenting pgc v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(coerce_unsized)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(unsize)]
[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 `pgc`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name pgc src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern crossbeam_deque=/opt/rustwide/target/debug/deps/libcrossbeam_deque-690cfb03fcea0b05.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-db88f49d9e5662e7.rmeta --extern libc=/opt/rustwide/target/debug/deps/liblibc-306930453d48610a.rmeta --extern mimalloc=/opt/rustwide/target/debug/deps/libmimalloc-d2e829a9ad2aa72a.rmeta --extern num_cpus=/opt/rustwide/target/debug/deps/libnum_cpus-a649e169d2b8392f.rmeta --extern parking_lot=/opt/rustwide/target/debug/deps/libparking_lot-c5725e72cf17ec88.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-4dd24e75b0d10f91.rmeta --extern scoped_threadpool=/opt/rustwide/target/debug/deps/libscoped_threadpool-c264290d6b37b518.rmeta --extern threadpool=/opt/rustwide/target/debug/deps/libthreadpool-da070efd8fcecef7.rmeta --extern time=/opt/rustwide/target/debug/deps/libtime-2e2ad3d8b9eed9d3.rmeta --cap-lints=warn --crate-version 0.3.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "849b339e2e1dbd5611ecf22b1ae5d4d98a377a76bc3e23d07cd418fafd439941", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "849b339e2e1dbd5611ecf22b1ae5d4d98a377a76bc3e23d07cd418fafd439941", kill_on_drop: false }`
[INFO] [stdout] 849b339e2e1dbd5611ecf22b1ae5d4d98a377a76bc3e23d07cd418fafd439941