[INFO] fetching crate backslash 0.2.0...
[INFO] documenting backslash-0.2.0 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate backslash 0.2.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate backslash 0.2.0 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 backslash 0.2.0
[INFO] finished tweaking crates.io crate backslash 0.2.0
[INFO] tweaked toml for crates.io crate backslash 0.2.0 written to /workspace/builds/worker-7/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] [stderr]     Blocking waiting for file lock on package cache
[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]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] 7408228aa2a392b1b134348424b033f5d6ef5e4ba1c2125a243c435b102c9587
[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" "7408228aa2a392b1b134348424b033f5d6ef5e4ba1c2125a243c435b102c9587", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7408228aa2a392b1b134348424b033f5d6ef5e4ba1c2125a243c435b102c9587", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7408228aa2a392b1b134348424b033f5d6ef5e4ba1c2125a243c435b102c9587", kill_on_drop: false }`
[INFO] [stdout] 7408228aa2a392b1b134348424b033f5d6ef5e4ba1c2125a243c435b102c9587
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] c9c74d3a6434cacfa8a038689bbe3d0abba5e757b3e6f646278a25d32c7235cc
[INFO] running `Command { std: "docker" "start" "-a" "c9c74d3a6434cacfa8a038689bbe3d0abba5e757b3e6f646278a25d32c7235cc", kill_on_drop: false }`
[INFO] [stderr]  Documenting backslash v0.2.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.45s
[INFO] running `Command { std: "docker" "inspect" "c9c74d3a6434cacfa8a038689bbe3d0abba5e757b3e6f646278a25d32c7235cc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9c74d3a6434cacfa8a038689bbe3d0abba5e757b3e6f646278a25d32c7235cc", kill_on_drop: false }`
[INFO] [stdout] c9c74d3a6434cacfa8a038689bbe3d0abba5e757b3e6f646278a25d32c7235cc