[INFO] cloning repository https://github.com/scottwillmoore/rust-primer
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/scottwillmoore/rust-primer" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscottwillmoore%2Frust-primer", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscottwillmoore%2Frust-primer'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3987f1a197201a58362beba79573dd2edd187748
[INFO] documenting scottwillmoore/rust-primer 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%2Fscottwillmoore%2Frust-primer" "/workspace/builds/worker-9/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/scottwillmoore/rust-primer 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/scottwillmoore/rust-primer
[INFO] finished tweaking git repo https://github.com/scottwillmoore/rust-primer
[INFO] tweaked toml for git repo https://github.com/scottwillmoore/rust-primer written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/scottwillmoore/rust-primer already has a lockfile, it will not be regenerated
[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-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] 044c5fd5a29c2412186c1c8530c9306fcde216bd91b92f996374f07dd0edbc9b
[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" "044c5fd5a29c2412186c1c8530c9306fcde216bd91b92f996374f07dd0edbc9b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "044c5fd5a29c2412186c1c8530c9306fcde216bd91b92f996374f07dd0edbc9b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "044c5fd5a29c2412186c1c8530c9306fcde216bd91b92f996374f07dd0edbc9b", kill_on_drop: false }`
[INFO] [stdout] 044c5fd5a29c2412186c1c8530c9306fcde216bd91b92f996374f07dd0edbc9b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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] 6e7a254acf47489a171c892dd02a135a02c3dc6b942c5d1af8193dd38b1eb3aa
[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" "6e7a254acf47489a171c892dd02a135a02c3dc6b942c5d1af8193dd38b1eb3aa", kill_on_drop: false }`
[INFO] [stderr]     Checking libc v0.2.39
[INFO] [stderr]     Checking memchr v2.0.1
[INFO] [stderr]     Checking aho-corasick v0.6.4
[INFO] [stderr]     Checking regex v0.2.10
[INFO] [stderr]     Checking docopt v0.8.3
[INFO] [stderr]  Documenting primer 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:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iterator_step_by)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 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 `primer`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name primer 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 docopt=/opt/rustwide/target/debug/deps/libdocopt-2ccd9d2aed3b77ea.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-bb9b33becc2d2dd2.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-a24fced8b9dbb86f.so --cap-lints=warn --crate-version 0.1.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "6e7a254acf47489a171c892dd02a135a02c3dc6b942c5d1af8193dd38b1eb3aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6e7a254acf47489a171c892dd02a135a02c3dc6b942c5d1af8193dd38b1eb3aa", kill_on_drop: false }`
[INFO] [stdout] 6e7a254acf47489a171c892dd02a135a02c3dc6b942c5d1af8193dd38b1eb3aa