[INFO] cloning repository https://github.com/linyinfeng/syn-flood
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/linyinfeng/syn-flood" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flinyinfeng%2Fsyn-flood", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flinyinfeng%2Fsyn-flood'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 36d241ae4f3c533a45decc026e109732f0cae7e5
[INFO] documenting linyinfeng/syn-flood against 1.61.0 for beta-1.62-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flinyinfeng%2Fsyn-flood" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/linyinfeng/syn-flood on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/linyinfeng/syn-flood
[INFO] finished tweaking git repo https://github.com/linyinfeng/syn-flood
[INFO] tweaked toml for git repo https://github.com/linyinfeng/syn-flood written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/linyinfeng/syn-flood already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded pnet v0.30.0
[INFO] [stderr]   Downloaded no-std-net v0.6.0
[INFO] [stderr]   Downloaded pnet_macros_support v0.30.0
[INFO] [stderr]   Downloaded pnet_macros v0.30.0
[INFO] [stderr]   Downloaded pnet_base v0.30.0
[INFO] [stderr]   Downloaded ipnetwork v0.19.0
[INFO] [stderr]   Downloaded pnet_packet v0.30.0
[INFO] [stderr]   Downloaded pnet_transport v0.30.0
[INFO] [stderr]   Downloaded ipnetwork v0.18.0
[INFO] [stderr]   Downloaded pnet_datalink v0.30.0
[INFO] [stderr]   Downloaded pnet_sys v0.30.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5ac23e3c877244b1f71df536834b61907680a4052ae74eaee76559488b243e2e
[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" "5ac23e3c877244b1f71df536834b61907680a4052ae74eaee76559488b243e2e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5ac23e3c877244b1f71df536834b61907680a4052ae74eaee76559488b243e2e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5ac23e3c877244b1f71df536834b61907680a4052ae74eaee76559488b243e2e", kill_on_drop: false }`
[INFO] [stdout] 5ac23e3c877244b1f71df536834b61907680a4052ae74eaee76559488b243e2e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 94d2b359f794abeb6e5624917d5d1030c948f0bea1913b273fd35954629b5dc9
[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" "94d2b359f794abeb6e5624917d5d1030c948f0bea1913b273fd35954629b5dc9", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.86
[INFO] [stderr]    Compiling serde v1.0.136
[INFO] [stderr]     Checking no-std-net v0.6.0
[INFO] [stderr]    Compiling unicode-segmentation v1.9.0
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling pnet v0.30.0
[INFO] [stderr]     Checking ansi_term v0.12.1
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]     Checking getrandom v0.2.4
[INFO] [stderr]     Checking pnet_sys v0.30.0
[INFO] [stderr]     Checking aho-corasick v0.7.18
[INFO] [stderr]     Checking pnet_base v0.30.0
[INFO] [stderr]     Checking clap v2.34.0
[INFO] [stderr]     Checking rand_core v0.6.3
[INFO] [stderr]     Checking pnet_macros_support v0.30.0
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]     Checking env_logger v0.9.0
[INFO] [stderr]     Checking ipnetwork v0.18.0
[INFO] [stderr]     Checking ipnetwork v0.19.0
[INFO] [stderr]     Checking pnet_datalink v0.30.0
[INFO] [stderr]    Compiling pnet_macros v0.30.0
[INFO] [stderr]    Compiling structopt-derive v0.4.18
[INFO] [stderr]     Checking structopt v0.3.26
[INFO] [stderr]     Checking pnet_packet v0.30.0
[INFO] [stderr]     Checking pnet_transport v0.30.0
[INFO] [stderr]  Documenting syn-flood v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(ip)]
[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 E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `syn-flood`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name syn_flood src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=9cc0c82c08c416ea -L dependency=/opt/rustwide/target/debug/deps --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-0f3b3f48753669d5.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-4c2b941844e2fcbb.rmeta --extern pnet=/opt/rustwide/target/debug/deps/libpnet-32e8a3018bcc27e0.rmeta --extern quick_error=/opt/rustwide/target/debug/deps/libquick_error-16f06d38f9b72840.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-b1b4b0f28bd31094.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-ab2b1f9818a20bf6.rmeta --cap-lints=warn --crate-version 0.0.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "94d2b359f794abeb6e5624917d5d1030c948f0bea1913b273fd35954629b5dc9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "94d2b359f794abeb6e5624917d5d1030c948f0bea1913b273fd35954629b5dc9", kill_on_drop: false }`
[INFO] [stdout] 94d2b359f794abeb6e5624917d5d1030c948f0bea1913b273fd35954629b5dc9