[INFO] cloning repository https://github.com/rustyhorde/libechoexec
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rustyhorde/libechoexec" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustyhorde%2Flibechoexec", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustyhorde%2Flibechoexec'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 315c423bd43ecf09e7e4933120d4fe027cebacd9
[INFO] documenting rustyhorde/libechoexec against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustyhorde%2Flibechoexec" "/workspace/builds/worker-1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rustyhorde/libechoexec 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 git repo https://github.com/rustyhorde/libechoexec
[INFO] finished tweaking git repo https://github.com/rustyhorde/libechoexec
[INFO] tweaked toml for git repo https://github.com/rustyhorde/libechoexec written to /workspace/builds/worker-1/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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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] 1ea9c0d8205088658a5d229e029a67b27dac4c9102111bae8699913e77b65456
[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" "1ea9c0d8205088658a5d229e029a67b27dac4c9102111bae8699913e77b65456", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1ea9c0d8205088658a5d229e029a67b27dac4c9102111bae8699913e77b65456", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1ea9c0d8205088658a5d229e029a67b27dac4c9102111bae8699913e77b65456", kill_on_drop: false }`
[INFO] [stdout] 1ea9c0d8205088658a5d229e029a67b27dac4c9102111bae8699913e77b65456
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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] 03413bff5fffc8df9820b57ab8594320c46c5c71e2304251dcd34a90e356f0a1
[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" "03413bff5fffc8df9820b57ab8594320c46c5c71e2304251dcd34a90e356f0a1", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.39
[INFO] [stderr]    Compiling pin-project-internal v0.4.23
[INFO] [stderr]     Checking bytes v0.5.6
[INFO] [stderr]     Checking arc-swap v0.4.7
[INFO] [stderr]     Checking futures-io v0.3.5
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling slog v2.5.2
[INFO] [stderr]     Checking tracing-core v0.1.15
[INFO] [stderr]    Compiling openssl-sys v0.9.58
[INFO] [stderr]     Checking futures-task v0.3.5
[INFO] [stderr]     Checking want v0.3.0
[INFO] [stderr]     Checking mio-uds v0.6.8
[INFO] [stderr]     Checking signal-hook-registry v1.2.1
[INFO] [stderr]     Checking tracing v0.1.19
[INFO] [stderr]     Checking http v0.2.1
[INFO] [stderr]     Checking slog-try v0.2.0
[INFO] [stderr]    Compiling openssl v0.10.30
[INFO] [stderr]    Compiling native-tls v0.2.4
[INFO] [stderr]     Checking http-body v0.3.1
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]    Compiling serde_derive v1.0.115
[INFO] [stderr]    Compiling getset v0.1.1
[INFO] [stderr]     Checking tokio v0.2.22
[INFO] [stderr]     Checking pin-project v0.4.23
[INFO] [stderr]     Checking futures-util v0.3.5
[INFO] [stderr]     Checking tokio-util v0.3.1
[INFO] [stderr]     Checking tokio-tls v0.3.1
[INFO] [stderr]     Checking h2 v0.2.6
[INFO] [stderr]     Checking futures-executor v0.3.5
[INFO] [stderr]     Checking futures v0.3.5
[INFO] [stderr]     Checking uuid v0.8.1
[INFO] [stderr]     Checking serde_json v1.0.57
[INFO] [stderr]     Checking hyper v0.13.7
[INFO] [stderr]     Checking hyper-tls v0.4.3
[INFO] [stderr]  Documenting libechoexec v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]    --> src/lib.rs:104:1
[INFO] [stdout]     |
[INFO] [stdout] 104 | #![feature(crate_visibility_modifier)]
[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 `libechoexec`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name libechoexec 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 futures=/opt/rustwide/target/debug/deps/libfutures-be348e7c76b32403.rmeta --extern getset=/opt/rustwide/target/debug/deps/libgetset-685268aa0ac47a1c.so --extern hyper=/opt/rustwide/target/debug/deps/libhyper-1f7e348f93302674.rmeta --extern hyper_tls=/opt/rustwide/target/debug/deps/libhyper_tls-8dae065fa9c1b523.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-db88f49d9e5662e7.rmeta --extern native_tls=/opt/rustwide/target/debug/deps/libnative_tls-7a9dc31afafccdc2.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-8be66c6bd8ae1f20.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-91b29b6f02b48749.so --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-48aa58e6e4483833.rmeta --extern slog=/opt/rustwide/target/debug/deps/libslog-3c1c3df238513a2f.rmeta --extern slog_try=/opt/rustwide/target/debug/deps/libslog_try-d367d67962cf6755.rmeta --extern tokio=/opt/rustwide/target/debug/deps/libtokio-59a45ab5aaf4ce54.rmeta --extern uuid=/opt/rustwide/target/debug/deps/libuuid-988f7a113e043592.rmeta --cap-lints=warn --crate-version 0.1.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "03413bff5fffc8df9820b57ab8594320c46c5c71e2304251dcd34a90e356f0a1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "03413bff5fffc8df9820b57ab8594320c46c5c71e2304251dcd34a90e356f0a1", kill_on_drop: false }`
[INFO] [stdout] 03413bff5fffc8df9820b57ab8594320c46c5c71e2304251dcd34a90e356f0a1