[INFO] cloning repository https://github.com/s-panferov/akta
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/s-panferov/akta" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fs-panferov%2Fakta", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fs-panferov%2Fakta'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 130910202fbf6a8ff7d091314c928cd484d9b215
[INFO] documenting s-panferov/akta against 1.54.0 for beta-1.55-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fs-panferov%2Fakta" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/s-panferov/akta on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/s-panferov/akta
[INFO] finished tweaking git repo https://github.com/s-panferov/akta
[INFO] tweaked toml for git repo https://github.com/s-panferov/akta written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/s-panferov/akta already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded ppv-lite86 v0.2.5
[INFO] [stderr]   Downloaded c2-chacha v0.2.2
[INFO] [stderr]   Downloaded getrandom v0.1.12
[INFO] [stderr]   Downloaded rand v0.7.0
[INFO] [stderr]   Downloaded futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded proc-macro-hack v0.5.9
[INFO] [stderr]   Downloaded futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded memoffset v0.5.1
[INFO] [stderr]   Downloaded nodrop v0.1.13
[INFO] [stderr]   Downloaded futures-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded crossbeam-epoch v0.7.2
[INFO] [stderr]   Downloaded arrayvec v0.4.11
[INFO] [stderr]   Downloaded crossbeam-deque v0.7.1
[INFO] [stderr]   Downloaded libc v0.2.62
[INFO] [stderr]   Downloaded futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded syn v1.0.5
[INFO] [stderr]   Downloaded futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-executor-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded proc-macro2 v1.0.3
[INFO] [stderr]   Downloaded futures-io-preview v0.3.0-alpha.18
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "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] 7f3afb3831dda6f1ee6557f065d87a6e2240cf02c63f8fedda49a32fb71a797f
[INFO] running `Command { std: "docker" "start" "-a" "7f3afb3831dda6f1ee6557f065d87a6e2240cf02c63f8fedda49a32fb71a797f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7f3afb3831dda6f1ee6557f065d87a6e2240cf02c63f8fedda49a32fb71a797f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7f3afb3831dda6f1ee6557f065d87a6e2240cf02c63f8fedda49a32fb71a797f", kill_on_drop: false }`
[INFO] [stdout] 7f3afb3831dda6f1ee6557f065d87a6e2240cf02c63f8fedda49a32fb71a797f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fe6452e6cc2a94343377f65d4b27dad34cf3a93a2c11cdd427b5b3f496d15a45
[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" "fe6452e6cc2a94343377f65d4b27dad34cf3a93a2c11cdd427b5b3f496d15a45", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.3
[INFO] [stderr]    Compiling getrandom v0.1.12
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking c2-chacha v0.2.2
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]     Checking iovec v0.1.2
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking crossbeam-epoch v0.7.2
[INFO] [stderr]     Checking crossbeam-queue v0.1.2
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking tokio-io v0.1.12
[INFO] [stderr]     Checking crossbeam-deque v0.7.1
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking rand v0.7.0
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling proc-macro-hack v0.5.9
[INFO] [stderr]    Compiling futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-util-preview v0.3.0-alpha.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/futures-util-preview-0.3.0-alpha.18/src/lib.rs:4:38
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![cfg_attr(feature = "async-await", feature(async_await))]
[INFO] [stdout]   |                                      ^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `async_await` has been stable since 1.39.0 and no longer requires an attribute to enable
[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 E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `futures-util-preview`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "fe6452e6cc2a94343377f65d4b27dad34cf3a93a2c11cdd427b5b3f496d15a45", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fe6452e6cc2a94343377f65d4b27dad34cf3a93a2c11cdd427b5b3f496d15a45", kill_on_drop: false }`
[INFO] [stdout] fe6452e6cc2a94343377f65d4b27dad34cf3a93a2c11cdd427b5b3f496d15a45
