[INFO] fetching crate standalone-proc-macro2 0.2.2...
[INFO] documenting standalone-proc-macro2-0.2.2 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate standalone-proc-macro2 0.2.2 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate standalone-proc-macro2 0.2.2 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 crates.io crate standalone-proc-macro2 0.2.2
[INFO] finished tweaking crates.io crate standalone-proc-macro2 0.2.2
[INFO] tweaked toml for crates.io crate standalone-proc-macro2 0.2.2 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] 4a05262989936373c5bd43b25024a63f85566bc99e0f643673f27bb659ff693f
[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" "4a05262989936373c5bd43b25024a63f85566bc99e0f643673f27bb659ff693f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4a05262989936373c5bd43b25024a63f85566bc99e0f643673f27bb659ff693f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4a05262989936373c5bd43b25024a63f85566bc99e0f643673f27bb659ff693f", kill_on_drop: false }`
[INFO] [stdout] 4a05262989936373c5bd43b25024a63f85566bc99e0f643673f27bb659ff693f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] 3e2578ac75f68182307781e1ab92adc4515ce499d71c17cba3964a5bac8dbf16
[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" "3e2578ac75f68182307781e1ab92adc4515ce499d71c17cba3964a5bac8dbf16", kill_on_drop: false }`
[INFO] [stderr]     Checking rustc-ap-serialize v40.0.0
[INFO] [stderr]    Compiling rustc-ap-syntax v40.0.0
[INFO] [stderr]     Checking rustc-ap-rustc_cratesio_shim v40.0.0
[INFO] [stderr]     Checking parking_lot_core v0.2.14
[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/parking_lot_core-0.2.14/src/lib.rs:41:60
[INFO] [stdout]    |
[INFO] [stdout] 41 | #![cfg_attr(all(feature = "nightly", target_os = "linux"), feature(integer_atomics))]
[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/rustc-ap-serialize-40.0.0/lib.rs:24:1
[INFO] [stdout]    |
[INFO] [stdout] 24 | #![feature(rustc_private, box_syntax)]
[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/rustc-ap-serialize-40.0.0/lib.rs:25:1
[INFO] [stdout]    |
[INFO] [stdout] 25 | #![feature(core_intrinsics)]
[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/rustc-ap-serialize-40.0.0/lib.rs:26:1
[INFO] [stdout]    |
[INFO] [stdout] 26 | #![feature(i128_type)]
[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/rustc-ap-serialize-40.0.0/lib.rs:27:1
[INFO] [stdout]    |
[INFO] [stdout] 27 | #![feature(specialization)]
[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 compile `parking_lot_core`.
[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] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "3e2578ac75f68182307781e1ab92adc4515ce499d71c17cba3964a5bac8dbf16", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3e2578ac75f68182307781e1ab92adc4515ce499d71c17cba3964a5bac8dbf16", kill_on_drop: false }`
[INFO] [stdout] 3e2578ac75f68182307781e1ab92adc4515ce499d71c17cba3964a5bac8dbf16
