[INFO] cloning repository https://github.com/m4dcoder/rust-examples
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/m4dcoder/rust-examples" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fm4dcoder%2Frust-examples", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fm4dcoder%2Frust-examples'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6994d0db922a61021ea3628e8d650f5a1f9037f2
[INFO] documenting m4dcoder/rust-examples against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fm4dcoder%2Frust-examples" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/m4dcoder/rust-examples 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 git repo https://github.com/m4dcoder/rust-examples
[INFO] finished tweaking git repo https://github.com/m4dcoder/rust-examples
[INFO] tweaked toml for git repo https://github.com/m4dcoder/rust-examples written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/m4dcoder/rust-examples 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-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" "+1.46.0" "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] 1e314ab09f85e4f8861ab10a138f5794b8248413d048401b114de8c604e4eca5
[INFO] running `Command { std: "docker" "start" "-a" "1e314ab09f85e4f8861ab10a138f5794b8248413d048401b114de8c604e4eca5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1e314ab09f85e4f8861ab10a138f5794b8248413d048401b114de8c604e4eca5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1e314ab09f85e4f8861ab10a138f5794b8248413d048401b114de8c604e4eca5", kill_on_drop: false }`
[INFO] [stdout] 1e314ab09f85e4f8861ab10a138f5794b8248413d048401b114de8c604e4eca5
[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" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a4cd4f7e16261a00f4ccd496d6f23d96f48645a4da3067e9fe73e45433e07b94
[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" "a4cd4f7e16261a00f4ccd496d6f23d96f48645a4da3067e9fe73e45433e07b94", 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.18
[INFO] [stderr]    Compiling syn v1.0.33
[INFO] [stderr]    Compiling libc v0.2.71
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling serde_derive v1.0.114
[INFO] [stderr]    Compiling version_check v0.9.2
[INFO] [stderr]    Compiling serde v1.0.114
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling pkg-config v0.3.17
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]    Compiling serde_json v1.0.55
[INFO] [stderr]    Compiling cc v1.0.54
[INFO] [stderr]    Compiling proc-macro-hack v0.5.16
[INFO] [stderr]     Checking futures-core v0.3.5
[INFO] [stderr]     Checking slab v0.4.2
[INFO] [stderr]     Checking bytes v0.5.5
[INFO] [stderr]     Checking fnv v1.0.7
[INFO] [stderr]    Compiling pin-project-internal v0.4.22
[INFO] [stderr]     Checking itoa v0.4.6
[INFO] [stderr]    Compiling unindent v0.1.6
[INFO] [stderr]    Compiling inventory v0.1.7
[INFO] [stderr]     Checking pin-project-lite v0.1.7
[INFO] [stderr]    Compiling regex-syntax v0.6.18
[INFO] [stderr]     Checking once_cell v1.4.0
[INFO] [stderr]     Checking foreign-types-shared v0.1.1
[INFO] [stderr]    Compiling openssl v0.10.29
[INFO] [stderr]     Checking tinyvec v0.3.3
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling httparse v1.3.4
[INFO] [stderr]     Checking futures-io v0.3.5
[INFO] [stderr]     Checking futures-sink v0.3.5
[INFO] [stderr]    Compiling native-tls v0.2.4
[INFO] [stderr]     Checking pin-utils v0.1.0
[INFO] [stderr]    Compiling smallvec v1.4.0
[INFO] [stderr]     Checking try-lock v0.2.2
[INFO] [stderr]     Checking openssl-probe v0.1.2
[INFO] [stderr]     Checking tower-service v0.3.0
[INFO] [stderr]    Compiling encoding_rs v0.8.23
[INFO] [stderr]     Checking percent-encoding v2.1.0
[INFO] [stderr]     Checking mime v0.3.16
[INFO] [stderr]     Checking dtoa v0.4.6
[INFO] [stderr]     Checking base64 v0.12.2
[INFO] [stderr]     Checking futures-channel v0.3.5
[INFO] [stderr]     Checking http v0.2.1
[INFO] [stderr]     Checking foreign-types v0.3.2
[INFO] [stderr]    Compiling lock_api v0.3.4
[INFO] [stderr]     Checking unicode-bidi v0.3.4
[INFO] [stderr]     Checking futures-task v0.3.5
[INFO] [stderr]    Compiling unicase v2.6.0
[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/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] [stderr]    Compiling num-traits v0.2.12
[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] [stderr]    Compiling indexmap v1.4.0
[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 `lock_api`.
[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 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" "a4cd4f7e16261a00f4ccd496d6f23d96f48645a4da3067e9fe73e45433e07b94", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a4cd4f7e16261a00f4ccd496d6f23d96f48645a4da3067e9fe73e45433e07b94", kill_on_drop: false }`
[INFO] [stdout] a4cd4f7e16261a00f4ccd496d6f23d96f48645a4da3067e9fe73e45433e07b94