[INFO] cloning repository https://github.com/cmtt/jab
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/cmtt/jab" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcmtt%2Fjab", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcmtt%2Fjab'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a3c78ee1741dcd96dfd973a3011c4358dacfe457
[INFO] documenting cmtt/jab 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%2Fcmtt%2Fjab" "/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/cmtt/jab 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/cmtt/jab
[INFO] finished tweaking git repo https://github.com/cmtt/jab
[INFO] tweaked toml for git repo https://github.com/cmtt/jab written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/cmtt/jab 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]  Downloading crates ...
[INFO] [stderr]   Downloaded dynasmrt v0.5.2
[INFO] [stderr]   Downloaded syn v1.0.13
[INFO] [stderr]   Downloaded dynasm v0.5.2
[INFO] [stderr]   Downloaded proc-macro2 v1.0.7
[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" "+beta-2020-08-29" "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] dcba9c69e115d96eb9cb4f39734b5e1153d9cabb8e273f0552ea8d9407b7135d
[INFO] running `Command { std: "docker" "start" "-a" "dcba9c69e115d96eb9cb4f39734b5e1153d9cabb8e273f0552ea8d9407b7135d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dcba9c69e115d96eb9cb4f39734b5e1153d9cabb8e273f0552ea8d9407b7135d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dcba9c69e115d96eb9cb4f39734b5e1153d9cabb8e273f0552ea8d9407b7135d", kill_on_drop: false }`
[INFO] [stdout] dcba9c69e115d96eb9cb4f39734b5e1153d9cabb8e273f0552ea8d9407b7135d
[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" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a506097fdb35d103b5766633c97588bbf1b35218ea6d1453c8b06f7a37e7287a
[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" "a506097fdb35d103b5766633c97588bbf1b35218ea6d1453c8b06f7a37e7287a", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.7
[INFO] [stderr]    Compiling syn v1.0.13
[INFO] [stderr]    Compiling stable_deref_trait v1.1.1
[INFO] [stderr]    Compiling byteorder v1.3.2
[INFO] [stderr]     Checking memmap v0.7.0
[INFO] [stderr]    Compiling owning_ref v0.4.0
[INFO] [stderr]     Checking dynasmrt v0.5.2
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling dynasm v0.5.2
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/dynasm-0.5.2/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(proc_macro_diagnostic)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/dynasm-0.5.2/src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(proc_macro_span)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[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 compile `dynasm`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "a506097fdb35d103b5766633c97588bbf1b35218ea6d1453c8b06f7a37e7287a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a506097fdb35d103b5766633c97588bbf1b35218ea6d1453c8b06f7a37e7287a", kill_on_drop: false }`
[INFO] [stdout] a506097fdb35d103b5766633c97588bbf1b35218ea6d1453c8b06f7a37e7287a