[INFO] fetching crate racer 2.1.37...
[INFO] documenting racer-2.1.37 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate racer 2.1.37 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate racer 2.1.37 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 crates.io crate racer 2.1.37
[INFO] finished tweaking crates.io crate racer 2.1.37
[INFO] tweaked toml for crates.io crate racer 2.1.37 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate crates.io crate racer 2.1.37 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-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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] c56ec87e1cd67a82a463c2120d7cea3240fd9992e1d56e43f90284b3da5db9a9
[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" "c56ec87e1cd67a82a463c2120d7cea3240fd9992e1d56e43f90284b3da5db9a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c56ec87e1cd67a82a463c2120d7cea3240fd9992e1d56e43f90284b3da5db9a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c56ec87e1cd67a82a463c2120d7cea3240fd9992e1d56e43f90284b3da5db9a9", kill_on_drop: false }`
[INFO] [stdout] c56ec87e1cd67a82a463c2120d7cea3240fd9992e1d56e43f90284b3da5db9a9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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] 44a8c5d72a47514cf124552965e326d50509a8feb5ca7932bf9bc4f87f4f238f
[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" "44a8c5d72a47514cf124552965e326d50509a8feb5ca7932bf9bc4f87f4f238f", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling cc v1.0.53
[INFO] [stderr]     Checking smallvec v1.2.0
[INFO] [stderr]     Checking rustc-ap-rustc_graphviz v671.0.0
[INFO] [stderr]     Checking annotate-snippets v0.8.0
[INFO] [stderr]     Checking rustc-ap-rustc_fs_util v671.0.0
[INFO] [stderr]     Checking humantime v2.0.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling rustc-rayon-core v0.3.0
[INFO] [stderr]     Checking lock_api v0.3.4
[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/smallvec-1.2.0/lib.rs:29:32
[INFO] [stdout]    |
[INFO] [stdout] 29 | #![cfg_attr(feature = "union", feature(untagged_unions))]
[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/smallvec-1.2.0/lib.rs:31:37
[INFO] [stdout]    |
[INFO] [stdout] 31 | #![cfg_attr(feature = "may_dangle", feature(dropck_eyepatch))]
[INFO] [stdout]    |                                     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rustc-ap-rustc_lexer v671.0.0
[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-rustc_graphviz-671.0.0/lib.rs:278:1
[INFO] [stdout]     |
[INFO] [stdout] 278 | #![feature(rustc_private, nll)]
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking memmap v0.7.0
[INFO] [stderr]     Checking jobserver v0.1.21
[INFO] [stderr]     Checking termize v0.1.1
[INFO] [stderr]     Checking ena v0.14.0
[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 `rustc-ap-rustc_graphviz`.
[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[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lock_api-0.3.4/src/lib.rs:91:34
[INFO] [stdout]    |
[INFO] [stdout] 91 | #![cfg_attr(feature = "nightly", feature(const_fn))]
[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] [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: build failed
[INFO] running `Command { std: "docker" "inspect" "44a8c5d72a47514cf124552965e326d50509a8feb5ca7932bf9bc4f87f4f238f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "44a8c5d72a47514cf124552965e326d50509a8feb5ca7932bf9bc4f87f4f238f", kill_on_drop: false }`
[INFO] [stdout] 44a8c5d72a47514cf124552965e326d50509a8feb5ca7932bf9bc4f87f4f238f