[INFO] fetching crate modus_ponens 0.11.2...
[INFO] documenting modus_ponens-0.11.2 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate modus_ponens 0.11.2 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate modus_ponens 0.11.2 on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate modus_ponens 0.11.2
[INFO] finished tweaking crates.io crate modus_ponens 0.11.2
[INFO] tweaked toml for crates.io crate modus_ponens 0.11.2 written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 969cb94b2a3e5b6f5b200bb395757df539308425161b76816e05a1091d7fcad7
[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" "969cb94b2a3e5b6f5b200bb395757df539308425161b76816e05a1091d7fcad7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "969cb94b2a3e5b6f5b200bb395757df539308425161b76816e05a1091d7fcad7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "969cb94b2a3e5b6f5b200bb395757df539308425161b76816e05a1091d7fcad7", kill_on_drop: false }`
[INFO] [stdout] 969cb94b2a3e5b6f5b200bb395757df539308425161b76816e05a1091d7fcad7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d3492f0054e8bd4740662d0ac5b6c9c2ef985901922cc7d8d325a04962340aff
[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" "d3492f0054e8bd4740662d0ac5b6c9c2ef985901922cc7d8d325a04962340aff", kill_on_drop: false }`
[INFO] [stderr]     Checking bumpalo v3.4.0
[INFO] [stderr]    Compiling pest_generator v2.1.3
[INFO] [stderr]    Compiling pest_derive v2.1.0
[INFO] [stderr]  Documenting modus_ponens v0.11.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:20:1
[INFO] [stdout]    |
[INFO] [stdout] 20 | #![feature(hash_set_entry)]
[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 `modus_ponens`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name modus_ponens 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 bumpalo=/opt/rustwide/target/debug/deps/libbumpalo-114d560023dcdd16.rmeta --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-cf2ba41b0aa9e937.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-958bf2a074a4960f.rmeta --extern pest=/opt/rustwide/target/debug/deps/libpest-dad74e028fc44105.rmeta --extern pest_derive=/opt/rustwide/target/debug/deps/libpest_derive-37dbb5d032baf9c3.so --extern proc_macro2=/opt/rustwide/target/debug/deps/libproc_macro2-17be1714580826fd.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-aa48b02cc1582459.rmeta --extern syn=/opt/rustwide/target/debug/deps/libsyn-db7c93b515feaec7.rmeta --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "d3492f0054e8bd4740662d0ac5b6c9c2ef985901922cc7d8d325a04962340aff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d3492f0054e8bd4740662d0ac5b6c9c2ef985901922cc7d8d325a04962340aff", kill_on_drop: false }`
[INFO] [stdout] d3492f0054e8bd4740662d0ac5b6c9c2ef985901922cc7d8d325a04962340aff