[INFO] cloning repository https://github.com/nicrgren/rsplacer
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/nicrgren/rsplacer" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnicrgren%2Frsplacer", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnicrgren%2Frsplacer'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b05baf5cdba6d29175523f5fe43951aa7c812a93
[INFO] documenting nicrgren/rsplacer against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnicrgren%2Frsplacer" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/nicrgren/rsplacer on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/nicrgren/rsplacer
[INFO] finished tweaking git repo https://github.com/nicrgren/rsplacer
[INFO] tweaked toml for git repo https://github.com/nicrgren/rsplacer written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/nicrgren/rsplacer already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f5aedd03c30236eb3b0aeee24829d3a7b02a409eadd141224c295cca7e1abc34
[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" "f5aedd03c30236eb3b0aeee24829d3a7b02a409eadd141224c295cca7e1abc34", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f5aedd03c30236eb3b0aeee24829d3a7b02a409eadd141224c295cca7e1abc34", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f5aedd03c30236eb3b0aeee24829d3a7b02a409eadd141224c295cca7e1abc34", kill_on_drop: false }`
[INFO] [stdout] f5aedd03c30236eb3b0aeee24829d3a7b02a409eadd141224c295cca7e1abc34
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 042ed4987d09a29ac054883b44b535b7cc8ada2b794ed8c35284688fd54135ae
[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" "042ed4987d09a29ac054883b44b535b7cc8ada2b794ed8c35284688fd54135ae", kill_on_drop: false }`
[INFO] [stderr]     Checking ansi_term v0.10.2
[INFO] [stderr]     Checking memchr v2.0.1
[INFO] [stderr]     Checking atty v0.2.3
[INFO] [stderr]     Checking textwrap v0.9.0
[INFO] [stderr]     Checking backtrace-sys v0.1.16
[INFO] [stderr]    Compiling structopt-derive v0.1.6
[INFO] [stderr]    Compiling failure_derive v0.1.1
[INFO] [stderr]     Checking backtrace v0.3.4
[INFO] [stderr]     Checking aho-corasick v0.6.4
[INFO] [stderr]     Checking clap v2.28.0
[INFO] [stderr]     Checking regex v0.2.3
[INFO] [stderr]     Checking failure v0.1.1
[INFO] [stderr]     Checking structopt v0.1.6
[INFO] [stderr]  Documenting rsplacer v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(slice_patterns)]
[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 `rsplacer`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type bin --crate-name rsplacer src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern failure=/opt/rustwide/target/debug/deps/libfailure-7700e021bbfad22d.rmeta --extern failure_derive=/opt/rustwide/target/debug/deps/libfailure_derive-b3e5f4dddf938470.so --extern regex=/opt/rustwide/target/debug/deps/libregex-50955525552eedb0.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-48aa93afe8f210ef.rmeta --extern structopt_derive=/opt/rustwide/target/debug/deps/libstructopt_derive-4b343ae12a81a994.so --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "042ed4987d09a29ac054883b44b535b7cc8ada2b794ed8c35284688fd54135ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "042ed4987d09a29ac054883b44b535b7cc8ada2b794ed8c35284688fd54135ae", kill_on_drop: false }`
[INFO] [stdout] 042ed4987d09a29ac054883b44b535b7cc8ada2b794ed8c35284688fd54135ae