[INFO] fetching crate unmp 0.7.3...
[INFO] documenting unmp-0.7.3 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate unmp 0.7.3 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate unmp 0.7.3 on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate unmp 0.7.3
[INFO] finished tweaking crates.io crate unmp 0.7.3
[INFO] tweaked toml for crates.io crate unmp 0.7.3 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 38626c0c8d39daee130508eda28890824ad106acf682fc522fdffca450d22d0e
[INFO] running `Command { std: "docker" "start" "-a" "38626c0c8d39daee130508eda28890824ad106acf682fc522fdffca450d22d0e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "38626c0c8d39daee130508eda28890824ad106acf682fc522fdffca450d22d0e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "38626c0c8d39daee130508eda28890824ad106acf682fc522fdffca450d22d0e", kill_on_drop: false }`
[INFO] [stdout] 38626c0c8d39daee130508eda28890824ad106acf682fc522fdffca450d22d0e
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6985908236bba6b580a095b8f6b1eb4319bc82408837087f51e0a4207115ec7e
[INFO] running `Command { std: "docker" "start" "-a" "6985908236bba6b580a095b8f6b1eb4319bc82408837087f51e0a4207115ec7e", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling futures-core v0.3.21
[INFO] [stderr]     Checking spin_loop v0.1.1
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling crc16 v0.4.0
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]     Checking async-task v4.2.0
[INFO] [stderr]     Checking fixed-queue v0.3.11
[INFO] [stderr]     Checking unmp-id v2.0.0
[INFO] [stderr]    Compiling futures-task v0.3.21
[INFO] [stderr]    Compiling futures-util v0.3.21
[INFO] [stderr]     Checking getrandom v0.2.6
[INFO] [stderr]    Compiling atomic v0.5.1
[INFO] [stderr]    Compiling lock_api v0.4.7
[INFO] [stderr]     Checking spin v0.9.3
[INFO] [stderr]     Checking futures-intrusive v0.4.0
[INFO] [stderr]     Checking unmp-link v0.7.0
[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/unmp-link-0.7.0/src/lib.rs:6:12
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(const_btree_new)]
[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 `unmp-link` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "6985908236bba6b580a095b8f6b1eb4319bc82408837087f51e0a4207115ec7e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6985908236bba6b580a095b8f6b1eb4319bc82408837087f51e0a4207115ec7e", kill_on_drop: false }`
[INFO] [stdout] 6985908236bba6b580a095b8f6b1eb4319bc82408837087f51e0a4207115ec7e