[INFO] fetching crate jenga 0.1.10...
[INFO] documenting jenga-0.1.10 against master#394e1b40d264aa6928811919c1124fa248e7d802 for pr-73566
[INFO] extracting crate jenga 0.1.10 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate jenga 0.1.10 on toolchain 394e1b40d264aa6928811919c1124fa248e7d802
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate jenga 0.1.10
[INFO] finished tweaking crates.io crate jenga 0.1.10
[INFO] tweaked toml for crates.io crate jenga 0.1.10 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "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" "+394e1b40d264aa6928811919c1124fa248e7d802" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4d3890649d8c695b4eee9fef51c729e0b56805d64bed19e6342b00b7b2500fc4
[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" "4d3890649d8c695b4eee9fef51c729e0b56805d64bed19e6342b00b7b2500fc4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4d3890649d8c695b4eee9fef51c729e0b56805d64bed19e6342b00b7b2500fc4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d3890649d8c695b4eee9fef51c729e0b56805d64bed19e6342b00b7b2500fc4", kill_on_drop: false }`
[INFO] [stdout] 4d3890649d8c695b4eee9fef51c729e0b56805d64bed19e6342b00b7b2500fc4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "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] ac189caa70857b8e9ac70269668d2b52fa9fa37885c08f81b43abad9efddd02d
[INFO] running `Command { std: "docker" "start" "-a" "ac189caa70857b8e9ac70269668d2b52fa9fa37885c08f81b43abad9efddd02d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Documenting jenga v0.1.10 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0635]: unknown feature `const_refcell_new`
[INFO] [stdout]  --> src/lib.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(const_refcell_new)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: Could not document `jenga`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name jenga src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="alloc"' --cfg 'feature="default"' --cfg 'feature="std"' --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --cap-lints=forbid` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "ac189caa70857b8e9ac70269668d2b52fa9fa37885c08f81b43abad9efddd02d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ac189caa70857b8e9ac70269668d2b52fa9fa37885c08f81b43abad9efddd02d", kill_on_drop: false }`
[INFO] [stdout] ac189caa70857b8e9ac70269668d2b52fa9fa37885c08f81b43abad9efddd02d