[INFO] cloning repository https://github.com/sweetmandm/rust-cool
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sweetmandm/rust-cool" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsweetmandm%2Frust-cool", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsweetmandm%2Frust-cool'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cd0594f7950276256500408c16c730c8c5517e41
[INFO] documenting sweetmandm/rust-cool against 1.47.0 for beta-1.48-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsweetmandm%2Frust-cool" "/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/sweetmandm/rust-cool on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sweetmandm/rust-cool
[INFO] finished tweaking git repo https://github.com/sweetmandm/rust-cool
[INFO] tweaked toml for git repo https://github.com/sweetmandm/rust-cool written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/sweetmandm/rust-cool already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 56258207f46a0bb2565b19f3938efa116930dbafde0a2439a106a34c4ddcd9ce
[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" "56258207f46a0bb2565b19f3938efa116930dbafde0a2439a106a34c4ddcd9ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "56258207f46a0bb2565b19f3938efa116930dbafde0a2439a106a34c4ddcd9ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "56258207f46a0bb2565b19f3938efa116930dbafde0a2439a106a34c4ddcd9ce", kill_on_drop: false }`
[INFO] [stdout] 56258207f46a0bb2565b19f3938efa116930dbafde0a2439a106a34c4ddcd9ce
[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" "+1.47.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 29c01d1fe2d93d6cf1a745a623033de6201fdd45aa499697ec8384fc15ae364e
[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" "29c01d1fe2d93d6cf1a745a623033de6201fdd45aa499697ec8384fc15ae364e", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.7
[INFO] [stderr]    Compiling bit-vec v0.4.4
[INFO] [stderr]    Compiling vec_map v0.6.0
[INFO] [stderr]    Compiling lalr v0.0.2
[INFO] [stderr]    Compiling itertools v0.8.1
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling dirs v1.0.5
[INFO] [stderr]    Compiling atty v0.2.13
[INFO] [stderr]    Compiling term v0.5.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling bit-set v0.4.0
[INFO] [stderr]    Compiling redfa v0.0.2
[INFO] [stderr]    Compiling ascii-canvas v2.0.0
[INFO] [stderr]    Compiling plex v0.2.5
[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/plex-0.2.5/src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(proc_macro_diagnostic)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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/plex-0.2.5/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![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 `plex`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "29c01d1fe2d93d6cf1a745a623033de6201fdd45aa499697ec8384fc15ae364e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "29c01d1fe2d93d6cf1a745a623033de6201fdd45aa499697ec8384fc15ae364e", kill_on_drop: false }`
[INFO] [stdout] 29c01d1fe2d93d6cf1a745a623033de6201fdd45aa499697ec8384fc15ae364e
