[INFO] cloning repository https://github.com/TimUntersberger/wwm
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/TimUntersberger/wwm" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTimUntersberger%2Fwwm", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTimUntersberger%2Fwwm'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cf7fe96974f97f7f7a9e9d2dbb0e4ff969d46094
[INFO] documenting TimUntersberger/wwm against 1.47.0 for beta-1.48-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTimUntersberger%2Fwwm" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/TimUntersberger/wwm on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/TimUntersberger/wwm
[INFO] finished tweaking git repo https://github.com/TimUntersberger/wwm
[INFO] tweaked toml for git repo https://github.com/TimUntersberger/wwm written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/TimUntersberger/wwm already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: unused manifest key: package.log
[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-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" "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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", 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] 2f0bea3473994901923641e55f34be2749edf53dfc947ef5671d212d029a462a
[INFO] running `Command { std: "docker" "start" "-a" "2f0bea3473994901923641e55f34be2749edf53dfc947ef5671d212d029a462a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2f0bea3473994901923641e55f34be2749edf53dfc947ef5671d212d029a462a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2f0bea3473994901923641e55f34be2749edf53dfc947ef5671d212d029a462a", kill_on_drop: false }`
[INFO] [stdout] 2f0bea3473994901923641e55f34be2749edf53dfc947ef5671d212d029a462a
[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" "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" "+1.47.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 09beaa3ff35607ddfc54831495d1d906e7cc9aa025e161fde267191636768300
[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" "09beaa3ff35607ddfc54831495d1d906e7cc9aa025e161fde267191636768300", kill_on_drop: false }`
[INFO] [stderr] warning: unused manifest key: package.log
[INFO] [stderr]    Compiling libc v0.2.71
[INFO] [stderr]    Compiling syn v1.0.38
[INFO] [stderr]    Compiling pin-project-internal v0.4.23
[INFO] [stderr]     Checking once_cell v1.4.0
[INFO] [stderr]    Compiling serde v1.0.116
[INFO] [stderr]     Checking futures-io v0.3.5
[INFO] [stderr]     Checking object v0.20.0
[INFO] [stderr]    Compiling nix v0.17.0
[INFO] [stderr]     Checking fixedbitset v0.2.0
[INFO] [stderr]     Checking unicode-xid v0.2.0
[INFO] [stderr]     Checking lazycell v1.3.0
[INFO] [stderr]    Compiling winapi v0.3.8
[INFO] [stderr]     Checking ipnet v2.3.0
[INFO] [stderr]     Checking strum v0.18.0
[INFO] [stderr]     Checking instant v0.1.7
[INFO] [stderr]    Compiling hashbrown v0.8.2
[INFO] [stderr]    Compiling openssl-sys v0.9.58
[INFO] [stderr]    Compiling indexmap v1.5.1
[INFO] [stderr]     Checking tracing-core v0.1.14
[INFO] [stderr]     Checking miniz_oxide v0.4.1
[INFO] [stderr]     Checking lock_api v0.4.1
[INFO] [stderr]     Checking proc-macro2 v1.0.18
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lock_api-0.4.1/src/lib.rs:91:34
[INFO] [stdout]    |
[INFO] [stdout] 91 | #![cfg_attr(feature = "nightly", feature(const_fn))]
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking futures-task v0.3.5
[INFO] [stderr]    Compiling quote v1.0.6
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lock_api`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "09beaa3ff35607ddfc54831495d1d906e7cc9aa025e161fde267191636768300", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "09beaa3ff35607ddfc54831495d1d906e7cc9aa025e161fde267191636768300", kill_on_drop: false }`
[INFO] [stdout] 09beaa3ff35607ddfc54831495d1d906e7cc9aa025e161fde267191636768300
